Sensor to Track Whether Gas Pool Heater is Running

[pool512]

I am trying to plug a hole in my pool automation with Home Assistant, and have been stuck on the approach.

My pool pad includes a Pentair IntelliCenter, IntelliFlo pumps, etc. which all feed back to HA. My pool heater is a Raypak 406a propane, and doesn’t provide any data points beyond what comes from IntelliCenter.

So, I can tell (from IntelliCenter) whether the heat is “running” (really whether heat has been turned on), set temperature, etc. The problem is that sometimes the ignition fails and the heater just sits there with an error code on the screen.

After enough time, I could figure out that the temp isn’t rising as expected, but it’s often too late, and we realize at the last minute that the pool isn’t as warm as expected.

So, other than pool water temp, I’m trying to figure out a solution to determine if the heater failed to start.

It seems that the best options would include:

• Measure the exhaust temp (would be exposed to outdoor conditions and extreme heat)
• Determine if gas is flowing (not sure how this would work)
• Power usage (it’s hardwired into my pool panel, and it probably doesn’t draw much power during use anyway)

I can’t find anything similar in my searches, so I’m hoping somebody either has addressed this, or has a clever idea. I imagine there may be something electronically that could be monitored with a relay switch, but I don’t know anything about the electronics of the unit.

Thanks!

 

[JamesW]

Put a temp sensor after the heater to see the water exit temperature.

The temp rise is the difference from input to exit and it depends on total BTU and flow.

For 400,000 btu/hr, the temp rise will be:

Flow......................Temp rise.

40 GPM............16.8 Degrees F.

80 GPM..............8.4 Degrees F.