How is my pool heating connected? Newbie!


Well-known member
Mar 6, 2017
United Kingdom, England.
Hello all...

I am due to start a SLAM on my pool - hopefully over the weekend. First time i have had a pool so this is all new to me so excuse any silly questions i may ask.

I have got to know how the pool side of things run however one thing i am a little confused about is how it all connects to my gas heating.

To explain further:

I have 2 pipes coming out of the filter .... one goes into the ground - can i be correct in assuming this will go to my sewer ? (no screw tap connected to this).

The 2nd pipe connects to a big cover insulated pipe.

On the floor is a turn TAP1 (i am assuming when open this bypasses the heating system and straight out to the pool?)

Following on from this 2nd pipe there is TAP2 (assume this is for heating water as its insulated, there is a gauge at the top which is currently reading 10 degrees)

TAP2 & TAP3 create a loop in the central heating system, they are also connected to some type of (i think) heating exchanger (you can just about see this on the pic). From this 'heater exchanger' there is another pipe which connects to TAP5 (as there is a label on this saying OUT i assume it goes to the pool.

TAP1 AND TAP5 both line up if im looking in a straight line on the floor.

Strange - TAP3 is closed, if i open TAP4 it empties the water out my boiler system via the water release valve (which i assume was opened by the previous occupants). Im a little confused as to why it would be linked to the boilers water system? surely it should be separate?

TAP1, TAP2, TAP5 are jammed solid at the moment, not sure if they have been left open or closed!

I have added notes to following picture to give a idea of what is going on...


Well-known member
Mar 6, 2017
United Kingdom, England.
OK an hour or so of scratching my head, i think i may have worked it out.

TAP1 = by passes heating system and straight out to pool (thats the only thing i could think of, although it seem pointless as the water could flow via the heater exchange anyway regardless of wether it was being heated or not)
TAP2 = opens flow to swimming pool heater exchange
TAP3 & TAP4 = loop to boiler heating system
TAP5 = Water flowing from TAP1 through swimming pool heater exchange and then out via TAP5

I think thats it? any other suggestions would be good.

Basically am i correct in thinking TAP3 & TAP4 basically just heat the heat exchange, and then the pool water flow through the middle of it. (pretty simple now ive had a think!)


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
Aug 10, 2012
FL panhandle
There are a few reasons to bypass a heat exchanger. One is less flow resistance/head loss, another is if you need to run low pH for a while, 7.0, you want to bypass a copper heat exchanger so as not to damage it, another is if it fails or you want to winterize it you can still run the pool

Glad you figured out the rest, I was getting nowhere fast! :)

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