Hayward Heat Pro Heat Pump 110,000 BTU - HP21104T



Part # HP21104T

By Hayward Pool Products

  4.72 Average  



Part # HP21104T

Warranty 2 Year Warranty on manufacturer defects, 5 Year Warranty on Compressor, 10 Year Warranty on Titanium Tube

Product Description

Extend your pool season with a Hayward® HeatPro® heat pump.  Quiet and economical, heat pumps use the outside air and a titanium heat exchanger to generate heat for a fraction of the cost of gas.  Save up to 80% on operating costs.




*BTU ratings tested at 80 degree air temperature, 80 degree water temperature and 80% relative humidity
**COP ratings tested at 80% relative humidity


  • Titanium Heat Exchanger - excellent salt water and chemical corrosion resistance

    Exclusive 'Ultra Gold' evaporator coil corrosion resistant especially in coastal areas

    Quiet operation - quiet backyard environment

    AHRI certified performance - independent lab certified performance ensures value of purchase

    2in x 2 1/2in CPVC union plumbing connections - common union for installation or service, adapts to larger plumbing recommended for greater efficiencies

    Light weight - less than 250 lbs.


  • 2 Year Warranty on manufacturer defects
  • 5 Year Warranty on Compressor
  • 10 Year Warranty on Titanium Tube

Product Specifications

110,000 BTU
Coefficient of Performance:
60 Hz
Recommended Breaker Size:
Min Flow Rate:
30 GPM
Max Flow Rate:
75 GPM
31.25" Dia x 40" h
190 lbs.
6200 W
Compressor Size:
5 HP
Heat Exchanger:
Armour Coil
Electronic Temp Control:
Max Water Temp:
104 °F
Shipping Weight:
230 lbs.

?     Asked on 5/16/2017 by pete

Do new pool heat pumps come PRE-CHARGED? also if i (consumer) does install..(i am electrician) ..will it void any warranty? thanks for assistance

A     Answered on 5/17/2017 by Lennox H.

Hi, Pete. These units do come pre-charged. The unit has to be installed by a licensed professional. Since you're an electrician you can do that part but not the plumbing portion.

?     Asked on 5/16/2017 by blupools100

Hello, What is the kilowatts for this heater?

A     Answered on 5/17/2017 by Lennox H.

Hi, Blupools100. The input kilowatts of the unit is 6.2.

?     Asked on 5/14/2017 by

The product page says this is 110k BTU, but the photos say HP50TA, which is a 50k BTU unit. Which one is it?

A     Answered on 5/14/2017 by Stacey M.

Hello, the HP21104T is a 110k BTU unit, the picture is just to give you an example of model numbers and description of how label will look.

?     Asked on 5/13/2017 by jack

I live in Tucson AZ and am looking to use a heat pump from may-sept. pool is 16,000 gallons, 480 surface area. I think the correct heat pump is the Hayward Heat Pro Heat Pump 110,000 BTU - HP21104T What is your opinion?

A     Answered on 5/15/2017 by Lennox H.

Hi, Jack. The 110K BTU unit is sufficient to heat a 480 sq. ft. pool. I would recommend that you start with next size up whcih is the 125K BTU unit HP21254T.

?     Asked on 5/10/2017 by Bob Sullivan

I live near Chicago, IL and am looking in to what size heat pump i may need for an 18' x 33' oval above ground pool. would 125,00btu be large enough, or would a 140,000 btu model be neccessary? Thanks in advance!

A     Answered on 5/11/2017 by Lennox H.

Hi, Bob. I would recommend the 140K BTU unit.

?     Asked on 5/10/2017 by mike

does the HP31204T have cooling ?

A     Answered on 5/10/2017 by Lennox H.

Hi, Mike.  Inyo does have the Hayward Heat Pro Heat Pump 120,000 BTU Heat/Cool - HP31204T available.

?     Asked on 5/6/2017 by mark

I see the recommended rate of flow is 30-75 (HeatPro 110 BTU)aside from an expensive flow gauge how can one tell the rate of flow to have the pump perform properly ?

A     Answered on 5/6/2017 by Lennox H.

Hi, Mark. You can calculate the flow rate manually using the steps in our How To Size a Pool Pump which will put you close but a flow meter will much more accurate.

?     Asked on 5/4/2017 by Allen

I have a 30 foot round 54 in. sidewall above ground pool. Would this unit work for me? Local pool places say a heat pump is not a good idea for my size above ground pool because of my surface area and that I should only look at Gas heaters. I have friends with in ground pools that use propane and say the price of the gas use makes it not cost effective over the season so they cant even afford to use them. I live in central Ohio. Thanks!

A     Answered on 5/4/2017 by Scott W.

For that size of pool and your location I recommend the 140,000 BTU model, HP21404T. Running that heat pump from May through August with a run time of 8 hours a day you would be looking at about $130 for the month of May due to the initial heating cost and then June through August would be $40-70 per month.

?     Asked on 4/30/2017 by

What are the pros and cons of using a cover similar to a grill cover for a heat pump located under a roof edge and subject to North Florida rain and sun effects?

A     Answered on 4/30/2017 by Scott W.

If it fits there is anything wrong with using a grill cover for your heat pump.

?     Asked on 4/29/2017 by

Should i let pool water circulate through my heat pump when I am away for a while and heat pump is turned off?

A     Answered on 4/30/2017 by Lennox H.

Hi. I would not recommend doing that. If you do not have a bypass installed then you have no choice but to.

?     Asked on 4/25/2017 by Peter

What is the difference between the HP21254T and the HP21104T heat pumps ? What size pump will work best for a 16 x 32 x 5' deep in ground pool ?

A     Answered on 4/25/2017 by Scott W.

With your pool size you will want the 140,000 BTU model, HP21404T.

?     Asked on 4/23/2017 by Dave H.

I have a new 24' x 52" round pool being installed, I am 15 miles north of Boston, MA. It will also have a saltwater chlorine generator, I am looking for the right heat pump to install, I was looking at the Hayward HP21004T or the HP21104T. You have the best prices and after reading other reviews quality of service. Thank you

A     Answered on 4/24/2017 by Scott W.

For the location you live in I would not recommend a heat pump less than 125,000 BTU's, part number HP21254T.

?     Asked on 4/10/2017 by Rob

I have a 14 by 28 ft. pool going from 3.5 to 6ft. I live in Florida. What size pool pump would I need ? The 95,000 or 110,00 BTU? Thanks

A     Answered on 4/10/2017 by Scott W.

You could be with either one, but the 110,000 BTU unit is going to be the most efficient unit for you pool size and location.

?     Asked on 3/29/2017 by

I have 12 by 24 inground pool an it 3to6 deep. Which heater is good for my pool. I livr in Florida

A     Answered on 3/29/2017 by Scott W.

You would be good going with the 95,000 BTU model, HP21004T, but the 110,000 BTU model would be efficient as well.

?     Asked on 3/9/2017 by Tom Donovan

Does this price include Fl tax? My current heat pump has 13" clearance to the rear. Will this be a problem for the Hayward hp21104t?

A     Answered on 3/9/2017 by Megan C.

The current advertised price of $2,476.99 does not include Florida's State Sales Tax. You may add the item to the cart and enter your zip code, it will provide the tax for the heat pump or any other items. According to the owners manual on page 8 of 22, it states, A minimum of 2 feet (.6 m) of clearance from walls, shrubbery, equipment, etc. is required around the entire heat pump. This allows for ample air intake. A minimum of 6 feet (2 m) of clearance above the heat pump is required to prevent re-circulation of air. The unit should not be placed underneath eaves, decks, or porches, as this causes re-circulation of air.

?     Asked on 3/8/2017 by

Is a 110btu enough for a 13x33 3 to 6 foot deep kidney shape

A     Answered on 3/8/2017 by Scott W.

Yes, the HP21104T is big enough for your size pool.

?     Asked on 3/2/2017 by Chris

I have a 16 x 32 inground pool with an avg depth of about 5'-6'. I live in Long Island, NY, which unit would be best for me? I was thinking the 110,000 but might go with a 140,000. Thanks in advance.

A     Answered on 3/2/2017 by Scott W.

With a pool 19,000-20,000 gallons and the location you live in I would recommend the 140,000 BTU model, HP21404T.

?     Asked on 2/28/2017 by Robert T Moosally

who is your dealer or installer for the Easthampton, NY area?

A     Answered on 2/28/2017 by Hector F.

We ship all product from our vendors across the country and unfortunately cannot provide that information. These vendors sell only to businesses. You may be able to get those lists if you have a qualified business license/permit for a related industry.

?     Asked on 2/24/2017 by CARLOS PAIVA

how to replace temperature sencor

A     Answered on 2/27/2017 by Andy O.

Hello Carlos- Unfortunately we do not have this information. We recommend contacting Hayward's tech support at 908-355-7995.

?     Asked on 2/19/2017 by Juan Conil

I live in Central Florida and I have a 35000 gallon pool. How big of a heater will I need for my pool?

A     Answered on 2/20/2017 by Scott W.

You will need the 140,000 BTU model, part number HP21404T. It will take a couple of days of continuously running the pump to get the water to your desired temperature but once it there that heat pump will regulate the temperature from the preset temperature of your choosing.

?     Asked on 2/16/2017 by Gene

what size electrical panel breaker is needed for the 110,000 BTU heat pro heat pump. Does this need to be a ground fault breaker?

A     Answered on 2/17/2017 by Lennox H.

Hi Gene, This unit requires a 60 amp breaker that should be ground fault which is NEC code compliant.

?     Asked on 2/15/2017 by Bruce Wardell

Just tried to turn my heater on in Florida and the code OP came up.. Any ideas?...

A     Answered on 2/15/2017 by Alan M.

According to the Hayward Heat Pro Heat Pump Owners Manual, the OP code indicates a temperature sensor failure, part #HPX2169. If you have additional questions regarding this issue, feel free to contact Hayward directly at 1-800-657-2287.

?     Asked on 1/31/2017 by Gabriel Fontenier

Hi i live in Las Vegas and I'm surprise they don't install the heater pump here its like no one knows that exist. Anyway i try to understand why and some answer is the concern about the very low humidity here. So is the humidity an issue to have those system working correctly ?

A     Answered on 2/1/2017 by Scott W.

That is not a problem. I use to live in Coachella Valley which is the desert just like Las Vegas and I had a heat pump/chiller for my pool which is what I would recommend. In the summer months where it is 120 every day you will want the chiller part on your heat pump and then with the winter months you will be happy you have your heat pump.

?     Asked on 1/17/2017 by Brian Jackson

I have a Hayward HP21104T heat pump the LP trouble code is on. Is this the low pressure switch bad or low freon causing this?

A     Answered on 1/18/2017 by Adam Y.

Good morning Brian, It could be either. The code will show for both. I would check the Freon level first. If the level is good then it is the switch.

?     Asked on 1/13/2017 by Trudi

We live in Florida, our pool is screened in so it doesn't get as warm as we would like. What size hayward heat pump do need to heat a 15000 to 16000 gallon in ground pool?

A     Answered on 1/16/2017 by Adam Y.

Good morning Trudi, The 110,00 Btu's will work good. But you could use the 140,000 Btu's and it would run less.

?     Asked on 12/21/2016 by

is this model also a chiller?

A     Answered on 12/21/2016 by Alan M.

Hello- This model does not heat and cool the pool. I would recommend this model, Hayward Heat Pro Heat Pump 120,000 BTU Heat/Cool - HP31204T, to accommodate your heating and cooling options.

?     Asked on 11/12/2016 by

Is the HP21104T suitable for a 13000 gal pool

A     Answered on 11/14/2016 by Scott W.

What state do you live in, that will play a factor as well?

?     Asked on 11/10/2016 by MariaE

Hello, we are looking for an electrical water system for our salt system in ground outside pool. The size is 16x20, 11,000 Gal and 7 Ft max. We have a Hayward pump, please let us know what system do you recommend. Thanks

A     Answered on 11/10/2016 by Scott W.

That would be efficient for the size of your pool. I would not go any smaller than the 95k model.

?     Asked on 10/4/2016 by mike

Hello, we live in Arizona so yes its gets Hot !!!. Looking for a heat pump that will Heat in the winter and cool down in the summer months, pool size is 39' x 25' x max depth of 7 ft.. so I'm thinking we would need at least 108,000 btu . ?. Pentair/aqua pro/raypak/Jandy . What is recommended ? by looking at the pricing may have to finance lol. thank you

A     Answered on 10/5/2016 by Scott W.

The Pentair Ultra Temp, 460935, is a great model for the price as well as the RayPak, 013336. I used to live in the desert in Palm Springs, CA where as you know gets to 120 degrees everyday during the summer months. The chill feature on my heat pump was amazing. I would go to the gym for an hour, come back to jump in the pool and in that time frame it was nice and cool. I had the AquaCal, SQ120R, and in my 14 years of being in the pool industry it has been hard to find a heat pump at that caliber. If you have any further questions don't hesitate to email me back.

?     Asked on 10/4/2016 by Ken

Thank you for your quick response to my question regarding the shape of the Hayward HP21104T heat pump. If I may, please double check to make certain that this unit is square as pictured on your web site. I ask because all of other web sites show it as round and Hayward's installation guide shows it as round. The square units seem to bee the 100K btu, the 125K btu and the 140Kbtu units. The 110K units seems to be round. Could there be two styles of this unit?

A     Answered on 10/5/2016 by Scott W.

I apologize Ken for the false information, I have someone changing it right now. Out of the HeatPro heat pump models, the only one that is round is the 110,000 BTU model, HP21104T. All the rest are going to be square.

?     Asked on 10/4/2016 by Ken

The picture of the HP2110T on your web site shows a square unit. Isn't this model a round unit?

A     Answered on 10/4/2016 by Alan M.

This model is a square shaped unit.

?     Asked on 9/14/2016 by Bill

On 6/20/2016 Scott indicated in an answer that from a quality and endurance he would lean towards the RayPac over the Hayward. I was wondering if he could expand on the differences. Heat Pump replacement is no something I want to be doing on a regular basis.

A     Answered on 9/14/2016 by Scott W.

Raypak specializes in heating and cooling units. When it comes to replacement parts, in my experience, get an abundance of calls more on the heat pro than the Raypak. In my experience, I have seen personally the Raypak be more durable than the heatpro. Both great heat pumps, just letting you know what I have noticed and experienced.

?     Asked on 9/8/2016 by Jon

What brand of compressor is in a Hayward Heat Pro Heat Pump 110,000 BTU - HP21104T? Is it a Copeland compressor?

A     Answered on 10/4/2016 by Lennox H.

Hi, Jon. We're unable to get the actual manufacturer of the Hayward compressor. We do no have this item in-stock at the warehouse to check.

?     Asked on 8/19/2016 by Brian

I had a inspection on my Hayward Heat Pump and a error code came up P-5. Can you explain to me what that code means?

A     Answered on 8/25/2016 by Lennox H.

Hi Brian, The PS error code refers to the water pressure. Either the unit is not getting adequate water flow or the water pressure switch is bad.

?     Asked on 8/5/2016 by Monte

I live on the south shore of Long Island NY close to the water. I was looking to see if a 140k BTU electric heat pump would work with our different climate change. I keep get conflicting answers from different pool companies

A     Answered on 8/12/2016 by Lennox H.

Hi Monte, Heat Pumps can be used in you geographical location, however, once the temperature drops below 50 degrees it becomes insufficient.

?     Asked on 7/20/2016 by Corey

Hello, I wanted to check and see if this unit will be sufficient for my pool. I live in South Florida, have a freeform small 10,000 gallon pool with the following equipment: - hayward 1 1/2hp super pump - hayward 48 sq ft DE filter - hayward salt cell

A     Answered on 7/23/2016 by Lennox H.

Hi Corey, This Hayward Heat Pro Heat Pump 110,000 BTU is sufficient for your pool based on the pool size.

?     Asked on 7/15/2016 by David Gress

I hhave a 36000 gal pool which inludes a 800 gallon hot tub. The hot tub is isolated when used. will the 110,000 BTU version hold the pool at 82 and when I want to use the hot tub at 102? I live in NH where the nights cool down.

A     Answered on 7/16/2016 by Lennox H.

Hi David, I will recommend the HP21404T unit  instead along with a solar cover based on the info provided.

?     Asked on 7/6/2016 by kevin

what is minimum gallons per minute input requirement I know there is one as spec says it will shut down

A     Answered on 7/7/2016 by Alan M.

The minimum flow rate is 30 GPM (gallons per minute).

?     Asked on 7/3/2016 by tim

I have a haywood pool heater hp21104tc with a haywood pum[ 4 speed variable and a haywood de filter.With the pump set continually at 3300 why does P5 show up a few hours after backwashing? Have backwashed 4 times in the last 2 weeks yet P5 still comes up. The pump and heater are brand new.

A     Answered on 7/6/2016 by Lennox H.

Hi Tim, The filter media may need to be replaced or thoroughly cleaned.

?     Asked on 7/3/2016 by tim

i have a haywood titanium heat pump with a haywood variable speed pump does the pump have to be at maximim rpm to make the heat pump run? if so should I have gotten just a single speed pump 1 1 /2 HP pump?

A     Answered on 7/4/2016 by Alex V.

Tim, Depending on the pump model, you will need to increase the rpms when you need to use the heater. It doesn't necessarily have to be at max rpms.

?     Asked on 6/28/2016 by Scott

My heat pump turns on and will heat the pool to 84 that what I want but it will not maintain the temp. It is not kicking on and off I have to turn it on ever time what am I doing wrong

A     Answered on 7/3/2016 by Lennox H.

Hi, The unit may need to be inspected to find out why the unit is not heating automatically.

?     Asked on 6/23/2016 by JOANNA

On this 110k heat pump do you need "2" 3 way valve 1.5x2 NVR LUBE or just one for installation

A     Answered on 6/26/2016 by Lennox H.

Hi Jonna, You will need (1) 3 Way Valve, (1) 3 way tee and a check valve to install this unit.

?     Asked on 6/20/2016 by mike

What size heat pump would be best for a 27K Gal 36 L & 26&17 width - 9 feet deep end and 3.5 feet shallow. Which Heat Pump and what is the best price?

A     Answered on 6/20/2016 by Scott W.

I would either go with the RayPak 133K or the Hayward 140K unit. That would be the size you need for your size pool. As far as quality and durability between the two, me personally, would go with the RayPak.

?     Asked on 6/16/2016 by Davef

Hello. I have a 27' round above ground pool. Which unit will I need to properly heat it? I am in NJ. Thank you.

A     Answered on 6/16/2016 by Scott W.

The 110,000 would work fine for your pool, the 125,000 would get the job done faster which would save you money.

?     Asked on 5/31/2016 by martin

Good morning I need to have the exact shipping weight and crate dimensions since i need to export this product by air to Mexico. I appreciate your prompt response Martin Bossler

A     Answered on 6/2/2016 by Lennox H.

Hi Martin, The shipping weight of this unit is 230 lbs. Shipping dimensions are 48" x 48" x 51".

?     Asked on 5/23/2016 by George Delo

I have an in-ground 20,000 gallon pool with 2" lines. Will this pump work with it and what is the shipping time?

A     Answered on 5/28/2016 by Joe S.

Yes, this Heat Pump will work for that size pool. Please keep in mind it is best to also use a solar blanket to retain the heat that has been added to the pool. Lead time for any heat pump would be 5-6 business day's

?     Asked on 5/13/2016 by joe

Does this come with supplies to hook up the electrical?

A     Answered on 5/13/2016 by Alan M.

Hello Joe, The Hayward Heat Pro Heat Pump 110,000 BTU comes with couplings to attach the heat pump to your plumbing, but it does not come with an electrical cable to connect to your breaker box. I would recommend you contract a licensed electrician to perform that part of the installation.

?     Asked on 5/11/2016 by Todd Vanderleelie

Can I use this unit with 1 1/2" lines Thanks

A     Answered on 5/12/2016 by Hector F.

Yes you can use 1.5 inch lines as long as the max horse power on your pump is no more than 1.5.

?     Asked on 5/4/2016 by katie

Will this unit also cool my pool?

A     Answered on 5/4/2016 by Alan M.

Hello Katie, This unit will NOT heat and cool your pool. Here is a link to the Jandy Pro Series Heat Pump 137,000 BTU Heat/Chill that would fulfill your request.

?     Asked on 4/24/2016 by Don

Hello, If I purchase a Hayward Pro heat pump from you and have it installed by a registered plumber will the warranty be valid should I have any problems with the unit?

A     Answered on 4/25/2016 by Alan M.

Hello Don, We always recommend equipment installations are performed by licensed electrician and pool equipment installers. Should you have any questions on Hayward's warranty coverage, feel free to contact them directly at 1-908-355-7995.

?     Asked on 4/14/2016 by David

I have The Hayward Heat Pro Heat Pump 110,000 BTU (HP21104T) for a 13,000 gallon pool. Can I install the Heat Pump on a 15 deg. angle? My slab has a slope to it.

A     Answered on 4/14/2016 by Alan M.

Hello David, The according to the Heat Pump Pro HP21104T Installation Guide, the heat pump should be installed on level ground (page 4). Feel free to reference the installation guide or contact the manufacturer directly if you have additional questions. Thank you!

?     Asked on 4/9/2016 by John Kraigenow

What is the normal decibel level when this unit is running. I have a neighbor that likes to complain about noise.

A     Answered on 4/11/2016 by Lennox H.

Hi John, Hayward does not list the exact decibel of these units, but the HeatPro-Brochure implies that these units are under 60 dB.

?     Asked on 3/30/2016 by Terry

I have a Hayward Heatpro HP21004T about five years old. The metal connector from the compressor to the condenser has corroded and linked out all the refrigerant. Would this be covered under the compressor warranty?

A     Answered on 3/30/2016 by Lennox H.

Hi Terry, Unfortunately we're unable to answer your question. You will have to contact Hayward at 908.351.5400 to find out.

?     Asked on 3/29/2016 by Rod Perry

My old heat pump has a bypass valve between water in and water out on the out side of the unit . Should I reuse it or is it necessary ?.

A     Answered on 3/29/2016 by Scott W.

I would reuse the valve for the times you're not using the heat pump and needing that extra flow rate.

?     Asked on 3/26/2016 by Timothy

My pool is a volleyball pool 14'x28' it is 5.5' in the middle and slopes to 3' at either end. is this the correct unit, amount of BTU we should be looking for our in ground pool?

A     Answered on 3/29/2016 by Lennox H.

Hi Timothy, This unit can be used to heat your pool, however I Would recommend the HP21254T.

?     Asked on 3/26/2016 by Rod Perry

What is the footprint size of this unit

A     Answered on 3/26/2016 by Lennox H.

Hi Rod, This unit has a footprint of 31-1/4" DIA x 40" H.

?     Asked on 3/21/2016 by Mike Baldwin

I have a 18x36 oval shaped in-ground pool approximately 8' deep end and 4'shallow end. What heat pump would be the right fit for me. I would like to maintain 85 degrees. Plumbing and pump system is located 10' to pool. I live in MA.

A     Answered on 3/22/2016 by Lennox H.

Hi mike, I would recommend either the HP21254T or the HP21404T for your size pool.

?     Asked on 3/1/2016 by R

How well do heat pumps work in southern California. Currently its 75 degrees with 47 percent humidity. Could a heat pump bring my 18,000 gallon pool up to 82 degrees?

A     Answered on 3/2/2016 by Megan C.

The Hayward HP21004T would be a good fit for your location and pool size.The Temperature Set point: Pool and spa mode range is 50-104°F (21-40°C). (As listed in the Hayward Owners Manual pg.12 of 22 for the HP21104T) Please click here to view the Owners Manual for the Hayward HeatPro.

?     Asked on 2/14/2016 by Steve

I have a 21ft round above ground pool.I have a 220v line already run with a 40 amp circuit. Will I be able to use 50btu pump or the 110 btu pump is only option? I live in central NJ.

A     Answered on 2/15/2016 by Alex V.

Steve, Based on the pool size, I would recommend the 95k BTU Hayward Heat Pro. Please note that the heat pump needs adequate ambient temperature and humidity to operate correctly.

?     Asked on 12/15/2015 by Peggy

Is this heat pump and the 125, 000 and 140,000 heat pumps the same loudness. I would have to install it close to a lanai along with my other pool pump. I am wondering if the noise is going to be too much.?

A     Answered on 12/16/2015 by Brian M.

I spoke to the technicians at Hayward ( 908-355-7995 ) and was told there is no difference is sound level between the 110,000, 125,000 or the 140,000 BTUs. As for how loud it will be, he could not say since it depends on the size of the pump, the plumbing size and any other obstacles the water may encounter on its way to the the heat pump.

?     Asked on 12/10/2015 by Jim

I'm a pool technician and I have a customer with a heat pro heat pump. We normally service Jandy equipment and my resources are limited with this heater. The heat pump will not cut on and the a/c code is flashing on the display. The control pad is not responsive and power was cut several times to reset. In coming power is OK and transformer voltage is 28v. Any other ideas? Ambient temp today was 57 degrees F.

A     Answered on 12/10/2015 by Joe S.

Hello Jim, the Outside temperature too low. Low ambient air temperature will cause the unit to not work properly. The outside air temperature to exceed below 60ºF.

?     Asked on 11/26/2015 by don

what size pool heater fo 18x36 pool

A     Answered on 11/30/2015 by Joe S.

Hello Don, this is going to be a good size for this size pool. We also would recommend purchasing a solar cover to maintain the heat that has been added to the pool. PART#SC-BS-000044 

?     Asked on 10/27/2015 by

My neighbor has this and the water pump is humming so loud I can't sleep as its close to my bedroom. What can I cover it with and does it have to stay on 24/7...thank you 4 your reply

A     Answered on 10/27/2015 by Joe S.

Hello, with Heat Pumps you can not cover them with any cover or walls. They are like AC units and have a set requirement for clearance.

?     Asked on 10/9/2015 by Ron

Need the part number for the water pressure switch on a HP21104T

A     Answered on 10/9/2015 by Hector F.

The part number for this water pressure switch is 6224-32.

?     Asked on 9/25/2015 by

What size Heat pump for 13000 Gal

A     Answered on 9/30/2015 by Lennox H.

Hi, The Hayward Heat Pro Heat Pump 110,000 BTU (HP21104T) would be good for a 13,000 gallon pool.

?     Asked on 9/7/2015 by Gina

What BTU heat pump heater do I need for a 40,000 gallon inground pool?

A     Answered on 9/11/2015 by Lennox H.

Hi Gina, I would recommend the Hayward Heat Pro Heat Pump 140,000 BTU (HP21404T) for a 40,000 gallon pool.

?     Asked on 8/30/2015 by Thomas

Unit is flashing P5 when its off, pump is off. Is this normal? Thanks!

A     Answered on 9/2/2015 by Lennox H.

Hi Thomas, Yes it would be normal for the Heat Pump to display PS if the pump is off. That indicate low or no water flow.

?     Asked on 8/26/2015 by Dick C

Is there a winter cover for the Hayward HP21104T heat pump? If yes, where do I find one?

A     Answered on 8/26/2015 by Lennox H.

Hi Dick, The Pool Heat Pump Cover - One Size Fits All will work with this unit.

?     Asked on 7/23/2015 by tom

can this unit also cool?

A     Answered on 7/24/2015 by Hector F.

Negative. These Heatpro units are only for heating

?     Asked on 7/10/2015 by tom pasmore

what is the warranty on your heat pumps

A     Answered on 7/10/2015 by Andy O.

Tom- The Manufacture's Warranty on the Hayward Heat Pro Heat Pump 110,000 BTU HP21104T is as follows :2 Year Warranty on manufacture defects,5 Year Warranty on Compressor,10 Year Warrant on Titanium Tube.

?     Asked on 6/20/2015 by NORMAN


A     Answered on 6/20/2015 by Hector F.

This code means that the pressure switch itself is bad or the water flow is low. Start with cleaning and or removing the filter then testing to see if after that the flow increases. Also make sure that there are no turned valves bypassing flow through the unit. There could be a number of reasons that water flow decreases but start there and if that does not solve it, move to testing potential pump issues.

?     Asked on 6/15/2015 by Anthony

How does air temp affect the heater performance? If it is 30 degrees outside will I be able to heat my pool to a comfortable temperature?

A     Answered on 6/16/2015 by Dennis R.

Anthony - Here is a heat pump calculator by Raypak that show you the impact of severals factors on a heat pumps performance including outside temperature: Raypak Heat Pump Calculator. Select a comparable Raypak Heat Pump at the top: 5350ti = 95K BTUs; 6350ti =117K; 8350ti = 133K. Fill in your local parameters and click "Recalculate". Change the parameters to see their impact on the heat pump's performance.

?     Asked on 6/14/2015 by

Does this unit require a GFi breaker when installing?

A     Answered on 6/15/2015 by Joe S.

Installation Check: Verify the heat pump installation is compliant per this installation manual. Verify the electrical connection is correct by ensuring the breaker is sized correctly and the wiring is per the National Electric Code (NEC). Reference this installation manual to ensure that the plumbing is installed correctly.NOTICE: Service to be conducted ONLY by an EPA Certified Service Technician.

?     Asked on 6/6/2015 by Kar

Can I use this heat pump in a salt water pool? If so any specific cleaning necessary ? Thanks.

A     Answered on 6/7/2015 by Alex V.

Kar, Yes the heat pump can be used with a salt water pool. It is highly recommended that a check valve and bypass are installed. It is also recommended that the outside of the unit be sprayed down periodically if it is near the pool.

?     Asked on 6/3/2015 by

installing a chlorinator after the heater. What kind of check valve or backflow preventer should be used?

A     Answered on 7/9/2015 by Joe S.

Yes you should install the chlotinator after the equiment and yes a back flow should be used. PART#25830-400-000 

?     Asked on 6/3/2015 by

I have a Hayward Heat Pro (110,000 BTU) and 19,500 gallon pool. I have not been able to get the pool above 85 degrees and the outside temperature has been in the low 80's. Does the outside temperature need to be higher for the hear pump to raise the pool temperature?

A     Answered on 6/3/2015 by Joe S.

Hello Bill, Yes Ambient temperature and humidity play a factor in the BTU Heating Performance. Attached is a link explaining BTU HEATING PERFORMANCE

?     Asked on 5/25/2015 by Sumit

what size heater should be a good for 24 ft round pool and I am in the north east?

A     Answered on 5/27/2015 by Dennis R.

Sumit - A 110,000 BTU would be adequate for your size pool. Of course anything larger would heat your pool that much faster.

?     Asked on 5/23/2015 by Stan

will this heat my 18x40 pool 28,080 gallons, are there heaterS with remote access from my ipad

A     Answered on 5/23/2015 by Lennox H.

Stan, This Hayward Heat Pro Heat Pump 110,000 BTU can heat your pool. Depending on how fast you would like it heated, you can go with a larger size BTU unit. Heater Pumps by themselves does not have the capability to be accessed remotely, you will need to have to the heat connected to an  Pro Logic Automation Controller that has the capability to be access from your iPad.

?     Asked on 5/11/2015 by Rich

1. Is this the proper size heat pump for the following size pool: 14x17x28 mountain lake inground, 3.5 to 6.5 deep. 85 degrees desired temp. Centra PA 5/15 - 9/15. 2. Can this be run on an 30AMP circuit?

A     Answered on 5/11/2015 by Joe S.

Hello Rich, This heater requires a 60 amp breaker. For your size pool I would go no smaller then a 110BTU and maybe consider looking at the HP21404T

?     Asked on 5/9/2015 by Jim

I have a pool that is 13X24 (4' - 6' deep) with a 6X8 (3' deep) Spa attached. Will the Hayward 110,000 be the right size for me?

A     Answered on 5/9/2015 by Lennox H.

Jim, This Hayward 110,000 BTU Heat Pro Heat Pump will be good for your size pool.

?     Asked on 5/8/2015 by

What happening when it flash's LP? Model HP21002.

A     Answered on 5/8/2015 by Lennox H.

When the heat pump flashes "LP" when the low pressure switch detects that the refrigerant pressure is low.

?     Asked on 5/4/2015 by

What size heat pump in BTU's do I need to heat 14,000 gallons to about 85 degrees?

A     Answered on 5/4/2015 by Lennox H.

This Hayward Heat Pro Heat Pump 110,000 BTU will heat your pool however the higher the BTU's the faster it will heat your pool. You can go with the Hayward HeatPro Heat Pump 125,000 BTU or Hayward Heat Pro Heat Pump 140,000 BTU  for faster heating.

?     Asked on 5/2/2015 by Brian

Hi. I need to replace an older H-Series Millivolt 250 Propane. I live in TN. Pool size 32 X 15. Would the the Heat Pro be a recommendation for this area and pool size? Also considering a newer H-Series 250. Thanks in advance.

A     Answered on 5/2/2015 by Patrick P.

Hi Brian, Yes the 110,000 BTU Heat Pro would be adequate for you size pool. The benefit to the heat pump will be that it will cost much less to heat your pool over a gas heater. The downside to the heat pump is that it takes a little longer to heat the pool water over gas and once the outside temp. drops below 50 degrees they are inefficient. I actually have a heat pump and a gas heater on my pool and 99% of the time I use the heat pump and not the gas heater, so a heat pump would be my recommendation.

?     Asked on 4/26/2015 by Crissy

In the HP 21104T heater, i'm installing it in a area against the brick face of my home. To be specific in an enclosed fence with plenty of air space, no direct sunlight. Any suggestions, is this the right heater to fit my needs. Pool holds 10,000 gallons .

A     Answered on 5/2/2015 by Patrick P.

Hi Crissy, You will definitely want to make sure you have proper ventilation on all sides of the heat pump. Proper ventilation for this model is 24" of clearance on all sides of the heater. This heat pump would be great for a 10,000 gallon pool.

?     Asked on 4/24/2015 by Alex

Hi, does this unit includes wiring/connectivity for remote operation and will it be compatible with Jandy iAqualink system for remote operation? Thanks

A     Answered on 4/24/2015 by Lennox H.

Alex, This unit does not come with any wires for electrical or for connectivity for remote operation. You will have to contact Hayward Tech Support at (908) 355-7995 or Jandy at (800) 822-7933 to find out if this unit is compatible with your automation system.

?     Asked on 4/23/2015 by Frank

Can the pool pump and filter run without running the heater.

A     Answered on 4/23/2015 by Lennox H.

Frank, Yes it can. You can have the heat pump off and still run your pool pump. If you don't have an external bypass to the heat pump the water will still flow through the unit but not heat the water.

?     Asked on 4/21/2015 by sal

I'm installing a new electrical line for this Hp21104T heater What's the voltage, amperage and phase for this unit

A     Answered on 4/21/2015 by Lennox H.

Sal, You'll need a dedicated maximum fuse size of 60 Amps, minimum 35 amps, 240 Volts, 60 Hertz, 1 Phase to operated this unit.

?     Asked on 4/17/2015 by Gregg

If I install will it be warranted If service becomes necessary who will service Eatonton Ga

A     Answered on 4/17/2015 by Wes B.

Gregg, In order for this heater to maintain its warranty it would need to be installed by a licensed and ensured company with receipts of install. If service becomes necessary you would contact the manufacture.

?     Asked on 4/16/2015 by Sal

What type of pool cover is needed that's easy enough to take on and off every day to maintain pool temperature?

A     Answered on 4/17/2015 by Lennox H.

Sal, A solar blanket with a reel will be what you will need to easily cover and uncover your pool to maintain the pool temperature. The solar blanket is based on your pool size.

?     Asked on 4/3/2015 by Enoc

Can I install this unit next to an outside air conditioner compressor unit. Will this affect any of the efficiency of the unit or what it actually improve the efficiency due to the fact that the AC compressor unit blows out hot air.

A     Answered on 4/4/2015 by Lennox H.

Enoc, A minimum of 2 feet (.6 m) of clearance from walls, shrubbery, equipment, etc. is required around the entire heat pump. This allows for ample air intake. A minimum of 6 feet (2 m) of clearance above the heat pump is required to prevent re-circulation of air. I would consult a licence HVAC contractor about how the units efficiency is affected by each other.

?     Asked on 4/2/2015 by David Kerker

Is the Hayward HP21104T big enough or to big for a 13' x 25' 5'6" deep end?

A     Answered on 4/2/2015 by Wes B.

Hi David, Yes this Hayward heater (HP21104T) will be sufficient enough for a pool your size.

?     Asked on 4/1/2015 by

Unit is flashing "P5". What does this mean?

A     Answered on 4/1/2015 by Hector F.

The heat pump is actually displayng "PS" which stands for pressure switch. Either there is not enough water flow or the switch is bad. Bypass the filter to possibly increase the flow and test. If it is resolved then it is a filter issue. If not then it is the switch itself.

?     Asked on 2/5/2015 by Don

How well does the heat pump stand up to the chlorine in the water? As a heat pump, is it required to bury piping in the ground to transfer heat?

A     Answered on 2/5/2015 by Alex V.

Don, The heat pump will be able to withstand recommended chlorine levels (1-3 ppm). You will also want to monitor pH, alkalinity and calcium hardness as those levels can corrode the "guts" of the heat pump. The plumbing does not need to be buried as a majority of your pool plumbing is already buried.

?     Asked on 9/18/2014 by Guest

What is the weight of this pump? Thanks

A     Answered on 9/18/2014 by Patrick P.

The weight for this heat pump is 240 pounds.

?     Asked on 9/17/2014 by Guest

Can the heat pump be turned on and left on with a pool pump that is switched off at night with a timer? Will the heat pump sense the no flow and take care of itself? Is this an acceptable way to operate the heat pump?

A     Answered on 9/17/2014 by Patrick P.

Yes you can install it that way, The heat pump has a sitch that will turn off the heat pump if there is not enough water flow. If you have any further questions please feel free to reply to this email. In addition, you may view the entire ticket history or enter a response by visiting the link below.

?     Asked on 9/11/2014 by Guest

Can I install this heat pump indoors?

A     Answered on 9/11/2014 by Patrick P.

Unfortuantely Hayward does not recommend installing the heat pump indoors.

?     Asked on 7/10/2014 by Guest

I am replacing a Hayward HP21002, are the fittings for inflow and outflow the same size and same location on the HP21104T or will plumbing need modification?

A     Answered on 7/10/2014 by Patrick P.

The plumbing would be the same size and the ports are few inches off from the old location so there would be some slight plumbing modification

?     Asked on 10/8/2013 by Guest

Is the refrigerant in Hayward heat pumps environmentally safe?

A     Answered on 10/8/2013 by Patrick P.

Yes. Hayward uses R-410A refrigerant in all their heat pumps.

?     Asked on 10/8/2013 by Guest

Can a heat pump be installed under a deck?

A     Answered on 10/8/2013 by Patrick P.

No. Any installation that causes the air being discharged from the top of the heat pump to be recirculated back into the heat pump will cause a loss of capacity and efficiency in the heat pump. Installation of a heat pump under a deck, or a low over hang will allow the air being discharged to be drawn back in by the heat pump.

?     Asked on 10/8/2013 by Guest

Can a heat pump be installed indoors?

A     Answered on 10/8/2013 by Patrick P.

Generally no. Heat Pumps work by transferring heat from the surrounding air to the pool water. If a heat pump is installed indoors there must be a continuous supply of warm air from which the heat pump can extract heat. If you must heat the air in the room before the heat pump can extract that heat to heat the pool, there would be no benefit to the heat pump.

?     Asked on 10/8/2013 by Guest

If I have a large pool pump will I need to have a flow meter for the heat pump?

A     Answered on 10/8/2013 by Patrick P.

According to Hayward their heat pumps have a flow rate range of 30 to 70 GPM, with an optimum flow rate of 45 GPM. If your pump is capable of significantly more flow than this, a flow meter is recommended to insure the flow rate is within the prescribed range.

?     Asked on 6/28/2013 by Guest

Is the Hayward HP21104T the replacement for the HP21003T?

A     Answered on 6/28/2013 by Patrick P.

Yes, the Hayward HP21104T is the replacement for the HP21003T.

?     Asked on 1/24/2013 by Guest

Is the Hayward HP21104T a replacement for the HP21002?

A     Answered on 1/24/2013 by Patrick P.

Yes, the Hayward HP21002 has been replaced by the HP21104T.

?     Asked on 5/27/2012 by Guest

Is this the replacement for the Hayward HP2100TCOT2?

A     Answered on 5/27/2012 by Patrick P.

Yes this is the proper replacement for the HP2100TCOT2.

?     Asked on 5/27/2012 by Guest

Would this be the proper replacement for the Hayward HP2100TCO2?

A     Answered on 5/27/2012 by Patrick P.

Yes this heat pump is the suitable replacement for the Hayward HP2100TCO2 heat pump.

?     Asked on 5/12/2012 by Guest

This heat pump is labeled for an in-ground pool. Can it also be used for an above ground pool?

A     Answered on 5/12/2012 by Patrick P.

Yes, this heat pump can be used with an above ground pool. You just have to ensure that it is wired correctly. It needs a 60 amp dedicated circuit breaker and has to be wired directly to the circuit breaker box.


Est. Repair Time

1 to 2 hrs

Tools Needed

Socket Set

2     0

New heat pump

Written on 1/13/2017 by Guest

I bought this heat pump, Hayward Heat Pro Heat Pump 110,000 BTU, and saved a lot. It was delivered within a few days. The pump is working like a charm, my pool is now useable all year. In winter I set it to 85F and everyone in the family loves it.

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Review Summary

  (Average 4.72 out of 5 stars)
25 Rating
5 star:
4 star:
3 star:
2 star:
1 star:

The Most Helpful Review

13     1

 (5 out of 5 stars)  Great pool heater!

from Annville, PA ()

Pros: pleasant swimming condition, runs quietly and efficiently

Cons: price of purchase and installation

For years I have been tempted to buy a heater so I can enjoy my pool more by taking the chill off the water. I assumed it would be a very expensive proposition. Much to my delight, this heater works very well and my electric bills have shown much less of a bump then I expected. By covering the pool in the evening, it loses only a few degrees at night and quickly reheats just by sunlight. I have it set to go on if the water temp goes below 81 and it has not run once the entire month of July. I enjoy going into the pool in the evening, floating and chatting without feeling chilled by cool water. The grandkids love, love, love the warm water and swim for hours! We could not be more pleased with this product!

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The Most Recent Reviews

2     1

 (4 out of 5 stars)  Quality inground pool heatpump

from Central Virginia ()

Pros: Good Web site, fast delivery, quality product

Cons: On the expensive side.

Received the water heater less than a week after it was ordered. The heater was an in-kind replacement of the original heater which I had to replace because of wrong fully winterizing it. I installed by my self using new routing for PVC piping. Installation and putting it in service was easy. Unit started without any issues and I was able to heat up the 18000 gallons pool by 5deg F in about 5 hours.

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2     0

 (5 out of 5 stars)  Hayward Heat Pro 110k

from New Port Richey FL ()

Pros: Looks good, quiet, heats up well

Cons: None really

Delivery process and order process easy. Be aware though you will need help to move this unit. I managed by myself with a trolley and strap but it was heavy! Electrician wired from main panel to the other side of my home for $450. I plumbed in the heater and connected the power. Spent circa $100 on fittings etc. Very simple to operate and heats up my 9000 gallon pool in no time. Yet to see what impact is on my electric bill but use of s good quality solar cover will help.

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3     0

 (5 out of 5 stars)  Easy quick installation

from Fort Lauderdale, FL ()

Pros: Easy setup and connection, fairly quiet

Cons: Electrical hookup space limited

Ordered the pool heater and it got delivered yesterday 4pm. By 10pm I was done with installation, eg setting on the slab, making electrical connections and plumbing. Granted, everything was in place. The electrical hookup is very tight in space, they do have a coolant pipe right at the place where the conduit is supposed to go, but it works. The startup was without issues and the unit is fairly quiet. Comparable to a small air conditioner. I have a 15x30 pool, and starting temp was 70 degrees. We will see how long it will take to heat it up to 86.

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1     0

 (5 out of 5 stars)  Great heat pump

from Long Island, NY ()

Came very fast. In perfect condition. Was a little worried but the buy online was quick easy and professional. Great price compared to local pool store.

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0     2

 (3 out of 5 stars)  Heat Pump

from Dayton, OH ()

Pros: New Technology

Cons: Apparently the new technology

This new technology heat pump seems to be slower at heating the pool than my old technology heat pump. The delivery was totally screwed up by UPS. INYO responded to the order quickly shipping the unit within 1 day but UPS sent it to Columbus, OH terminal and then sent it to South Holland, IL (near Chicago) instead of to me in Dayton, OH.

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0     1

 (4 out of 5 stars)  Very Happy So Far

from Oxford, Ohio ()

Pros: Heats well

Cons: Costly to run, but they all are.

We just installed our unit in the middle of the summer here in Ohio. I was very pleased that we got at least an extra month out of our pool at the end of the season by having this heating unit.

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1     0

 (5 out of 5 stars)  Great Heat Pump

from Longisland NY ()

The hayward heatpro is a outstanding .. Keeps the pool ture to temperature that is set . Hayward has got it right with this heater. Shop around and this website was the best price for this heat pump .

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