Hayward Gas Heater Install questions

[ATX61]

Recently purchased a Hayward 400,000 BTU gas heater. Trying to get my plumbing lined out before I get into the install. Pic of pool pump/filter set up attached pic. Left side of pic is yellow mark where I plan to cut into plumbing to feed the heater. Right side of pic is where plan to cut into plumbing to flow heated water back to pool via the jets. Also attached is diagram from Hayward install manual.

Question: On the plumbing going to heater I was going to install a PVC T socket at yellow mark >> 2 way ball cut off valve or 2 way Jandy valve >> back flow preventer >> heater. I am no longer using tablets in the chlorinator so do I really need a back flow preventer? Could I just install a 3 way Jandy valve in place of the of the PVC T socket and cut off flow to chlorinator when using heater?

On the outlet from heater I was going to install a 2 way ball cut off valve or 2 way Jandy valve >> to return line with a PVC T socket.

Also, install manual says if system flow rate exceeds 125 gpm I need to install a manual bypass valve. Did not see any gpm specs on pool pump tag. How do I find out system flow rate?

Would appreciate any tips or advice on this install.

 

[kimkats]

I would make sure to have a bypass around the heater to be on the safe side. I would also have unions on either side of all equipment to add in repair or replacement. Good luck!

 

[wireform]

Be careful with a valve after the heater. If it gets closed by mistake while someone is diagnosing a problem you can mistakenly dead head the heater and trash the heater core. I like a Jandy diverter valve on the inlet side and check valve on the outlet.

 

[ajw22]

I don't see a yellow line in your pic in the PDF file. It makes it easier for all of us to review and respond to posts if you insert the pics directly into the message using the picture icon on the tool bar.

Cut your pipe between the filter output and the chlorinator. Filter output goes into a 3-way diverter valve. Diverter valve out goes into heater input.

Heater output goes to a check valve, then to a T, then to the chlorinator.

Connect other output from diverter valve to the T.

You now have a bypass valve and a CV protecting the heater from backflow from the acidic water of the chlorinator.

See pictures and diagrams in Heater Bypass - Further Reading

 

[ATX61]

Thanks for the replies. This all makes sense now. Will definitely be plumbing in a bypass.

 

[M_Melton]

Where are people buying gas heaters to install themselves??? this is the second thread I've seen.

 

[ATX61]

Where are people buying gas heaters to install themselves??? this is the second thread I've seen.

I bought mine at Swimming Pool Supplies Online - SwimmingPoolSupplyUSA it was on sale. Best price I could find from merchant with good reviews.