How To Install an In-Line Chlorinator


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Chlorinators allow you to add controlled amounts of chlorine into your pool. They are attached to the output pipe after the filter. To use, open the top of the mechanism, insert chlorine tablets, and then adjust the amount of the chlorine going into the pool. Typically, they are used in the summer when the pool is used more. There are two types of chlorinators: IN-LINE CHLORINATOR - is attached directly into the plumbing system and you cut out pieces of pipe and install the whole system. OFF-LINE CHLORINATOR - sits on a stand and has two hoses – INPUT and OUTPUT – that lead from the output pipe to the chlorinator. This is used when the plumbing system on your filter has minimal space. This guide shows you how to install a Powerclean Ultra in-line Chlorinator.

Step by Step


Step 1

Tools you will need: 1) Hacksaw 2) Felt Tipped Pen 3) PCV Glue

Step 2

Turn off electricity going to the pump motor via your fuse box, not just the timer. You don’t want the pump to turn on when you are doing this.

Step 3

Determine where you want to put the chlorinator. Freshly chlorinated water will reduce the life of both the filter and heater. ALWAYS put the chlorinator AFTER the filter and heater. Generally the chlorinator should be the last unit installed before going back to the pool.

Step 4

This system comes with fittings for 2” and 3” pipe. Determine what size you have and then put the Union Tailpiece together on both sides. Make sure the washer is seated properly and the fitting is tight.

Step 5

Position the assembly on the out-flow pipe after the filter and make a mark on each side of the fittings. Measure 3/4” in from the mark you just made and mark with felt pen. This is where we will cut the pipe. IMPORTANT: Make sure that the flow arrow is pointed in the right direction (towards the pool)

Step 6

Cut the pipe at the inside markings you just made.

Step 7

Gently pull back the pipes and insert the chlorinator to see if you have a good fit. Remove.

Step 8

Now put glue on the pipe, and on the inside of the chlorinator fittings. MAKE SURE THE FLOW ARROW IS POINTED IN THE RIGHT DIRECTION (towards the pool)

Step 9

Insert the chlorinator and hold straight up until the glue sets. Ideally, put a brick on one side of the chlorinator to support it.


(1 to 18 of 18)

 Posted: 5/28/2022 

I have chlorine generator that has stopped working, can I put an inline chemical dispenser in the same location.

InyoPools Product Specialist  Posted: 6/2/2022 

Yes, you can, but I would install a valve before the chlorinator to prevent backflush. A check valve is critical if there is a heater before the chlorinator.

 Posted: 4/17/2018 

Hello Hummy - It is common to see a slight increase in pressure when you install a chlorinator and check valve after the filter.

 Posted: 4/16/2018 

Ok so I installed my rainbow 320 in-line chlorinator and added a check valve. My sand filter pressure gauge before the chlorinator was installed was 12-15 after back wash. It new reads 16-19. Its not alarming more high but it has increased. Is that normal?

 Posted: 3/30/2018 

It is true that inline chlorinators seem to have less problems. However, off-line systems are still a good option. If you go the off-line route, I would suggest flushing it out with warm water and baking soda from time to time. This will prevent the build up of chlorine residue in the hoses and check valves.

 Posted: 7/12/2019 

My pipes come out at top of my filter is that ok with installing an in line chlorinater?

InyoPools Product Specialist  Posted: 7/16/2019 

An in-line chlorinator requires a horizontal length of pipe to be installed on. If you have a horizontal pipe that the chlorinator can mount to, then you can use it.

 Posted: 3/29/2018 

I have considered an off line chlorine feeder but from what I have read an in-line chlorine feeder is more efficient and less problematic. I am a novice at this pool equipment so someone could correct me.

 Posted: 3/27/2018 

Hello Hummy - Have you considered installing an off-line chlorinator? You wouldn't have to change the plumbing if you go that route.

 Posted: 3/27/2018 

My return line to the pool is hovering at roughly 2.5ft in the air. If I lower the line to ground level I will have to move several other components. However having my feeder 2.5ft in the air seems like bad idea.

InyoPools Product Specialist  Posted: 8/5/2017 

Doug - Because of the corrosive nature of the concentrated chlorine coming out of the chlorinator, it should always be installed after all other units. It should be the last unit before the returns to the pool.

 Posted: 8/5/2017 

Does it matter where the inline chlorinator is installed in relation to a heater and ozone/UV generator? The article says downstream from the filter. Does position of chlorinator in relation to these other 2 units matter? Thank you.

InyoPools Product Specialist  Posted: 4/18/2015 

randa - The check valve would go between the heater or filter on the inlet side of the chlorinator. If you have limited room, you might consider installing an off-line chlorinator. See "How To Install a Pool Off-Line Chlorinator".

 Posted: 4/16/2015 

I need an answer for the question about converting salt cell to inline chlorinator also. would like to place where cell was. also where to put check valve I have 13" between pipes


InyoPools Product Specialist  Posted: 4/8/2015 

Chlorinator - You might consider putting in an off-line chlorinator. This only requires you to drill two holes in your piping which could be plugged later. See our guide on "How To Install a Pool Off-Line Chlorinator" for detailed instructions.

Anonymous  Posted: 4/7/2015 

We have a salt system and are wanting to put in an inline chlorinator where the salt cell was. Is there a way to do it without having to cut any of the existing pipe? Incase we revert back to salt at some point.


InyoPools Product Specialist  Posted: 7/20/2014 

Ted – I would recommend installing the chlorinator outside the pool house for safety.

 Posted: 7/19/2014 

Should the chlorinator be installed inside or outside of the pool house for safety?