My heater will not stay running. Can get it to turn on and run for a few minutes but then goes out and can not be started again Thermocoupler is 5 years old

sounds like running out of gas pressure

If you have replaced the thermocoupler and it still wont stay lit then replace the gas valve.

You could tripping the high temp limit this will be located near the heat exchanger When it shuts how long does the blower motor stay running? Do you have a meter?

Thermocoupler is dirty or needs replaced. The thermocoupler is the copper looking tube that runs along the pilot tube. The flame has to hit the thermocoupler to generate milivolts to open the gas valve

Sounds like the thermocoupler may be bad

The thermocoupler is bad.Replace it,or if you can adjust it to where the thermocoupler is in the pilot flame.You know you have to hold the knob down for about 30 seconds or a minute,don`t you?If the flame will not touch the thermocoupler,it will not stay lit.You can cut a piece of copper tubing,or steel tubing to slidde over the old thermocoupler to make contact with the pilot flame,and it will work,if the thermocoupler is not in to bad of shape.

That bulb that is at the pilot flame must get hot. When you light the pilot hold the button down for several minutes and then turn on the main valve. If the pilot goes out the thermocoupler is defective and the main gas is shut off. That bulb I mentioned is the thermocoupler. Good Luck _Ned_

Make sure the thermocoupler is about 1/4 in in the flame of pilot. If it persists, as you say it is, the thermocoupler is defefective. It's that bulb in the pilot flame. Good Luck, Ned

It sounds like the thermocoupler is either not adjusted into the flame properly, or you may have gotten a bad one. The thermocouple is the main thing that makes the pilot work.

I'm told by Charmglow that the problem is the Thermocouple. iHowever,it took me several calls to get someone to admit this. They are sending a new thermocoupler. My heater is less than a year old and under warranty--but it's a shame things like this happen.

Originally I was told it could'nt be the thermocoupler as they normally last at least 5 years.

Try it--as it may solve your problem as well.