Polaris hot water heater not bringing water up to temperature

Zad

I've got a 4 year old 130,000 btu 50 gallon Polaris hot water heater. A few weeks ago the ignitor went out and I replaced it and it worked fine since. Now, the ignition cycle starts, the heater comes on and heats for 45 seconds and then the heater cuts out. I've got the temperature set at 50 degrees C and the water is coming out at 31 C. Intake and exhaust is clear and the intake filter is clean. Gas stove is working fine and a gas tech is coming today to check gas pressure to house which I suspect will test fine. What would you suggest, short of calling a HVAC tech, I look for next? Thanks.

Jamie Hall

45 seconds? Most likely one of the safeties on the unit isn't working properly or has failed -- or is sensing a real failure. Rollout switch, flame sensor... an overtempt switch other than the aquastat. Hard to say without knowing what's on there.

Zad

Gas Co came and supply is fine. Now, a few hours after the original post, the ignitor light is coming on for 3 seconds and going off, no hot water heat now. Ignitor has good continuity. Perhaps time to call for help.

hot_rod

Polaris had a really good flow chart trouble shooting guide, probably still on their website, if you don't have the original installation manual. But you will need a meter and experience using it to determine which component is causing the fail.

Zad

Thanks hot rod, I found the flow chart, based on what it sais I need a new ignition module.

Zad

I live in Canada and the Polaris support up here is pretty mediocre. I finally got in touch with Polaris USA and not only are they open weekends but their technicians are extremely well informed, excellent service and it is the ignition control module.

Zad

I replaced the ignition control module which was defective, however the appliance still did not run properly with the ignition cycle going through to firing, running for 3-10 seconds then cutting out. Removing either the exhaust or intake air pipes made the unit run properly so I removed the air filter and cleaned with water and this was the final cure. Previously I had cleaned it off with backflow air but the dirt had packed the filter fibers such that not enough air could get through and the appliance was cutting out. I will now wash or replace the air filter annually.

hot_rod

Good catch, I remember now that Polaris shipped with intake air filters.

Probably save a lot of expensive mod con repairs, having an intake air filter. The mod con may even tell you when the filter is plugged and intake air blocked alert.

thetrualbertan

Hello, my polaris hot water tank (Model # PR50-130-2NV) cuts out the main burner as well. I thought maybe it was the ignitor as they seem to double as flame sensor so I went uptown and got a new one. Installed that but same problem. I checked flue gas outlet outside my house and it's clean, ice free. Same with intake. Intake filter is clean as I have washed it out.

It's such a weird problem. Sometimes, the main burner will cut in and run without issue for 5 mins and bring water to temperature, other times it cuts out after like 10 seconds. It's all over the map really. There are no flashing errors when this happens.

Yellow ignition light turns on, blower does purge and shuts off, ignitor gets hot, gas valve opens when it should, blower turns on, gas ignites, red burner light turns on, unit runs and then cuts out. Red light turns off, yellow ignition light stays on, blower stays running and then shuts off after a bit. Then the cycle repeats. Blower turns back on, purge and so on.

It used to run great. It still is getting the water up to temperature, but with radiant heating going, the unit struggles to get there until the thermostat for the radiant is happy and shuts down the call for heat. The polaris then gets up to temperature after cutting out and restarting however many times it takes.

Could the burner be dirty? I don't really want to pull the burner as it looks like a serious pain to do. Something is cutting it out, I just don't know what the next step is. I plan to call an HVAC guy to come and take a look but the folks here don't deal with Polaris heaters much.

psb75

Judging from the original poster's experience here, your best bet would seem to be: contacting the excellent Polaris tech support. Free help/advise. What do you have to lose?