Part # R171016
Dimensions 20" L x 6" W x 6" D
The Pentair Rainbow 300 is a completely enclosed off line system ideal for existing pools where permanent installation into the return line is impractical. It top loads, requires no venting and lets you adjust the optimum chlorine/bromine feed rate for your pool. It operates on pressure side of pump. Spa chamber not included
1 Year Warranty
* Note: Consult your local authority to determine their guidelines if needed. Results may vary due to pool/spa equipment and many other factors.
I've noticed that the elbow check valve in the bottom of this unit frequently gets clogged with chlorine corrosion. This prevents the small ball bearing inside from moving and seems to prevent the chlorinated water from going to the pool. Is there any way to prevent this issue?
Hi. Unfortunately, there is no way to prevent corrosion from occurring since chlorine is highly corrosive. The parts used in the chlorinator should not corrode because of the material is made out of.
We are interested in installing the Rainbow offline unit in our 24K gal pool. Our plumbing (pump etc) was installed lower than the pool water line. Would we need a check valve if using the offline unit since it would be installed on plumbing lower then the pool waterline? Thanks!
Installing a check valve or two on the system in general would be a good idea in making service performed easier and safer.
Where do I buy the fittings for model 300? They were not in the box. Thanks!
Here you can find the Fittings for the Rainbow 300 Chlorinator
is this unit complete with hoses clamps and valve
Yes this Rainbow Off Line Chlorinator is complete with hoses clamps and valve
How much 3/8" tubing does it come with?
Yes, the tubing and all the connections will come with the chlorinator.
Does this chlorinator come with a screen inside ? Or do we just drop the 3 inch tablets in it? Mine did not come with an interior screen
The tabs are just dropped into the canister, a screen doesn't come with it.
I cannot find the correct manual for this and I have one, what size drill bit is recommended to drill the holes into the PVC. Can you provide a link for the manual as well. Thanks.
Hi DoubleD, A 3/8" hole is required for the installation of this unit, click link Rainbow 300 & 320 Chlorinator Owner's Manual for manual.
The base of the chlorinator is setting in pool room on concrete floor. Its hard to open. It has three holes in base. Is it ok to put a 24" by 24" plywood base and screw it down.
Yes, you can absolutely bolt this chlorinator down.
Does this feeder come with all the hoses and fittings shown above?
Hi Lee, The Rainbow 300 Offline Chlorinator does comes with hoses and fittings shown for installation.
looking for a feeder for a jacuzzi hot tub.
Hi Mark, You can use the Rainbow 300 Offline Chlorinator on a Jacuzzi hot tub. You will have to follow the installation instructions to insure the tubes is placed in the correct position.
It says to install on pressure side, would that mean I install it before my filter and heater, or on the return side after my heater?
You will want to install this after your equipment
I currently am using a hayward offline chlorinator. I am lucky to get one season in before it starts leaking (usually the lid). I would like to try the 300. Are the thread fittings for the tubing the same size? Also, what kind of lube do you use to keep the lid easy on and off?
Hi Rob, The tubing and fittings are different but the size hole drilled into the PVC will work.
Is bottom the inlet or the outlet? Is the inlet on the side and the outlet on the bottom? Just bought one yesterday help!
Yes the inlet would be coming in at the top of the base near the flow control and the outlet goes out through the bottom of the chlorinator.
Which Hayward offline chloronator would match rainbow 300 offline in performance . Have the Rainbow want to replace it with Hayward . Looks easier to open .
I've seen the Rainbow Offline chlorinator with a clear plastic chamber so you can see how much of the tablets are left. Do you sell the clear plastic chlorinator?
Hi John, Yes we do carry the Clear Rainbow 300C Chlorinator here. We also carry an Off-line Chlorinator by Custom Molded Products W/ a Clear Glass Lid.
What is the best way to replace the 90 degree elbow on the bottom of the Rainbow offline 300 chlorinator, do you try to do it in place or remove the unit to work on.
Jeff, You can remove the elbow from the unit with it in place or unscrew the tubes from the chlorinator and work on it.
What is the best way to keep the top lubricated for easy removal?
Jack, Every time you're placing chlorine tabs into the chlorinator make sure you lubricate the o-ring and the threads on the cap.
I'm having difficulty locating the pressure nuts for securing a 1/4" line to the outlets. Can I buy these seperately?
I have a variable speed pump and have been fine tuning the pump flow for my pool. What is the min psi / GPM required to run this?
To properly assess the appropriate psi and gpm for any pool we would need more specifications on your system and pool. Such as pvc diameter, total hp and service factor of the motor , filter make and model. and if solar is present. General average for psi is betwenn 7 and about 17 psi on the filter gauge and gpm is generally between 65 to 90. Many variables though.
Do all the necessary parts come with the Rainbow 300 Offline Chlorinator?
Yes, the Rainbow 300 comes with all the parts needed for installation. It comes with: the 1/4 in. feeder hoses, control valve and fittings.
Is there a maximum distance the Rainbow 300 chlorinator can be from where it taps into the pool plumbing lines?
Pentair does not mention a maximum distance but 8' of tubing is included with the chlorinator. We recommend that you contact Pentair directly for more information. Their technical support should be able to assist you. Their toll free number is 1-800-831-7133
I have a 35,000 Gallon in ground pool. Will the Rainbow 300 handle this size pool or do I need to go with bigger unit?
The Rainbow 300 chlorinator is good for pools 12-48k gallons, So, yes, this chlorinator is sufficient for your size pool.
What size tablets does the Rainbow 300 Offline chlorinator take? And how tablets at one time?
The Rainbow 300 chlorinator uses both 1" and 3" tablets. You will need (98) 1" tablets and (11) 3" tablets.
I have a Rainbow 300 Offline chlorinator, but it doesn't have the smaller cylinder piece in the picture on your website. What is this used for?
The long cylinder piece in the picture is an optional piece for 1" chlorine tablets.
I looked at the Rainbow 300 Chlorinator diagram and did not see any valve that would automatically release chlorine gas build up in the canister. Is that correct?
Yes, you are correct. There is not a valve to release off gas on the Rainbow 300 chlorinator and we are not aware of a chlorinator which has this feature. We have read through the different pool chlorinator manuals and they state that you want to always keep the pool return lines open to prevent gas build-up.
What is the difference between an inline and offline chlorinator?
An inline chlorinator would be plumbed directly inline with the plumbing. For an existing pool, this would mean a section of pipe would need to be cut out to install the chlorinator. An offline chlorinator attaches to existing plumbing by chlorinator tubing (holes would be drilled into existing pipe to attach the tubing.)
Do the parts come with this unit?
Yes this does come with the 1/4 in. feeder hoses, control valve and fittings.
Is there a feedback mechanism that tells the unit the chlorine balance in the pool? Is this a way for me to automate addition of clorine to keep it always at the correct level? Or, just another place to put the tab aside from the the drain basket?
There is a dial on this unit which has a setting from 1-10 If you set the dial on 1 it will be letting the least amount of chlorine to the pool and if you have it set at 10 this would send the most amount of chlorine to the pool. So you can automate the feed of chlorine to the pool but you will still need to manually test your water. We do not recommend placing tablets in the skimmer basket because this high concentration of chlorine goes directly back to your pump and can cause corrosion to your pool equipment. If you do not go with the automatic chlorinator we would recommend at least going with one of our floating chlorinators so you do not damage your equipment you may view our floating chlorinators here http://www.inyopools.com/chlorinators_floating.aspx
What kind of chlorine tablets do I use with this type of chlorinator? Do you sell them?
You can use either 1" or 3" tablets. We sell both - here is a link to the chlorine tablets: http://www.inyopools.com/chemicals_sanitizers.aspx
Less than 1 hr
Screwdriver, Adjustable Wrench
This offline chlorinator was the brand and model originally installed when my pool was new. It lasted about 13 years and I replaced it with a different low quality product—you get what you pay for as that model failed within 2 years. I therefore went back to this proven model. Installation was simple and took well under an hour using a flat-head screwdriver, thread-sealing (“plumber’s) tape and an adjustable wrench. Just make sure you have the flow direction (inlet line and outlet line set properly before tightening up everything.
(5 out of 5 stars) Great clorinator - easy to install
Reviewed By: Boman from FL ()
Pros: Easy to install
Cons: Probably as with all clorinators, gets caked with clorine sludge inside after a few years.
Comes with all parts needed. Least intrusive, only 1 hole in plumbing for intake and 1 hole in plumbing for output. Just drilled a few holes in concreate using hammer drill to mount the clorinator.
(5 out of 5 stars) Keepin' It Clean!
Reviewed By: TurnAroundToU from Richfield, OH ()
Pros: Easy to use, light weight
Cons: Chlorine seems to disintegrate the parts within 2-3 years.
Love this chlorinator for the price! Easy to install, fill and use. Lightweight and easy to store for the winter.
(5 out of 5 stars) Great Clorinator
Reviewed By: Tom P. from Bentleyville OH ()
Pros: easy to install, easy to use
This is a great chlorinator. It's easy to install and easy to use. It adjusts to hold the chlorine level where you want it to be. I highly recommend it.