I have noticed for the last month or so that my propane hot water heater will come on and run a few seconds and then turn off. In a few more seconds it will come back on and run and stay running the entire cycle. This happens 100% of the time. I have plenty of hot water and my CO2 detector is quiet as a mouse. What is going on?
Propane Water Heater Acting Weird
- Thread starter Gebo
- Start date
Does it have a pilot light or an electric igniter? I'm not an expert, but it sounds like the flame detector thermocouple (thanks Nukeman7) doesn't believe that it lit successfully the first time?
My experience with propane burning appliances is mostly limited to RV furnaces.
My experience with propane burning appliances is mostly limited to RV furnaces.
It might be a failing thermocouple on the water heater. I have seen somewhat similar behavior on a Jotul natural gas stove where it would briefly short cycle until warmed up enough to sustain the millivolt output necessary to keep the gas valve open.
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Yes, try cleaning it. I've cleaned mine, the flame sensor, I believe, with success over the years, with the same symptoms yours is demonstrating. Going on 16 years with this tank, all original.
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If it lights consistently, but the flame just shuts off inappropriately, it's not the igniter. The most likely issue is the thermocouple which is a sensor with a prong that it's heated directly by the flame and sends voltage to the controller which lets it know that the ignition event was successful. Basically, the thermocouple translates heat into a small current. If it's going bad and takes too long to send the signal, the controller shuts off the gas, waits a short time and tried to light it again.
It sounds like the thermocouple is taking too long to send a strong enough signal. The one that I purchased in the past for a furnace was cheap and easy to replace. Just a couple of wires and a few screws.
It sounds like the thermocouple is taking too long to send a strong enough signal. The one that I purchased in the past for a furnace was cheap and easy to replace. Just a couple of wires and a few screws.
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Your AO Smith unit has the fancy energy control touch panel, but the process for replacing the thermocouple would be similar to this video.
I agree with this 100
A dirty pilot will not heat the tcouple sufficiently leading to a relite. It`s suppressing it doesn`t lockout on first failure.
So if the flame isn't hot enough to heat the thermocouple fast enough, it won't stay lit. Makes total sense.
OK, I took it out and sandpapered the flat probe and the bent tube. Put it back in and it's working fine??? Well, at least on this
first start up. Will know after it heats up and I take a shower.. I forgot for 15 seconds that "righty tightly lefty loosey" doesn't work
on the gas connection.
first start up. Will know after it heats up and I take a shower.. I forgot for 15 seconds that "righty tightly lefty loosey" doesn't work
on the gas connection.
