Hayward Heater and water chemistry

[cscupp]

I purchased a Hayward HD100ID1 propane heater 3 years ago, and after a week of having it on this year, it started producing a lot of vapor and appears to have an internal leak. I am assuming the heat exchanger is leaking and have shut of power and gas. I am purchasing a replacement, but I would like to know if it is expected that water chemistry could cause this rapid deterioration of the heat exchanger.

Looking at the heater manual, it recommends the following levels:

CL: 1-3
pH : 7.4-7.6
TA : 80-120 ppm
CA : 200-400 ppm
Salt : 2700-5000 ppm

My pool chemistry in the last week has been :

FC : 6.5-8.5 (opening I overshot with liquid chlorine)
CC : 0.0
pH : 7.2 - 7.3
TA : 50
CH : 0 (fill water is post-treatment due to lack of bypass plumbing, and the treated water is very soft)
CYA : 60 - 70
Salt : 2700 ppm

The heater lists the effect of low levels for CH as "corrosive to heat exchanger".

I have always left the heaters out over the winter with the plumbing removed, but the gas line connected.

Should I try to get my CH levels up to 200 ppm prior to installing the new heater?

Which other levels would contribute most to corrosion?

Should I disconnect and move the heater inside for the winter? I have hesitated to touch any gas fixtures out of an abundance of caution, but if it is simple union to disconnect and then reconnect in the spring, I would be willing to do it.

Thanks,

 

[U2brothr]

I'm not an HVAC expert, but I would not touch any gas fixtures.

Bring up your CH levels so that the water isn't looking to leech minerals out of the pipes and metals prior to sending it through the heater. That is what will damage your heater. Soft water.

I just bought a brand new Raypak/Rheem 266K BTU digital heater. The huge machine is connected to a gas cut off valve. It was installed by a licensed HVAC professional. The connection that was done contains pipe dope on the union. It isn't supposed to be tampered with.

It will not be going inside for the winter. Go to youtube and I'm positive you will find a video of "how to winterize your Hayward".

It will involve removing water in the system and removing some drain plugs...... as well as shutting off the gas.

 

[ajw22]

Is_Calcium_Level_Important_to_Heaters?

Heaters tend to build up a thin layer of calcium carbonate on their internal surfaces over time. This thin layer acts as a barrier to physical metal erosion (from high flow rates of water) and chemical attack (from accidental pH drop). However, this film is not indestructible and it can come and go over time depending on CH and pH levels.

Seeing your pH at 7.2 concerns me that your pH dropped below 7 at times.

 

[cscupp]

Thanks for the link and information.

I have ordered calcium carbonate and will adjust CH prior to running the new heater.

I plan on adjusting pH (7.6) using washing soda, then TA(80) using baking soda, and salt (3000) prior to CH, using PoolMath between each adjustment for calculations.

Does this sound reasonable?

When adjusting CH, the calculation is saying I need almost 23 pounds of calcium carbonate. I assume I would do this in stages, testing between additions. Is 8 pounds at a time too much, too little?

Thanks again

 

[ajw22]

Your pH and TA are fine. Don’t touch them. Any pH in the 7s is fine. TA of 50 or above is fine. Once you switch to a SWG they will naturally rise.

And if you do need to raise pH use Aeration - Further Reading

See Recommended Pool Chemicals - Trouble Free Pool for how to add calcium.