What is a thermocouple on this warm morning heater Plus sensor please send photo

Sounds like its the thermocouple not working check the conection to the gas valve from the thermocouple .Also check that pilot flame is strong and blue and playing on the thermocouple

Please review this 2010 FIXYA Link first:

Questions Answers for warm morning gas heater

There is also this site that mentions a THERMOCOUPLE (that may be causing your problems)?

Gas WARM MORNING EUROSIT THERMOCOUPLE

NOW they talk about a $36 price (plus shipping) methinks? Take YOURS into a Home Depot / LOWES / ?? and get one for LOTS less!

Anthony

There must be a control knob that has high or low on it which you can turn

check the thermocouple. easy to replace. inexpensive

Thanks for photo link. Not a smart meter.
Just ordinary water heater gas control valve, with small circuit board to support error codes:
Copy following link for handy resources:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
http://www.thetankatwaterheaterrescue.com/forums/forum3/
http://waterheatertimer.org/How-to-replace-Honeywell-gas-control-valve.html
How the newer gas control valves are different: Old water heater had thermocouple which supplies very tiny current to gas control valve. When pilot light blows out, the thermocouple no longer sends tiny current and gas control valve shuts off gas to heater.
New gas water heaters have thermopile (just like modern furnaces and stoves), which is basically several thermocouples bunched together. So thermopile sends more current to gas control valve, and supplies enough current to power small circuit board. The circuit board records error events and issues simple error codes. If pilot blows out, then thermopile no longer sends current and gas control valve shuts off gas to heater.
Moreover, the new gas control valve can be repaired and replaced without removing from tank. So tank does not have to be drained... saving time and repair cost.
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Julie, the problem you're having with your DESA, Gas Glo Warm heater may be the result of a clogged Oxygen Depletion Sensor (ODS) which is part of the pilot. I have included a link on how to clean the pilot and the ODS, as well as the burner, that you can download and print for future reference.

http://www.desatech.com/techDocs/Cleaning%20Demonstrations.pdf

In addition, the thermocouple may be failing and will need to be replaced. To troubleshoot this, here is another link that will help you. http://www.desatech.com/techDocs/Thermocouple%20Troubleshooting.pdf


If after doing all of the above and you fin it's necessary to replace the Thermocouple, You can purchase one from A & B Sales

pilot could be blocked needscleaning or thermocouple could be loose connection , or you may need to replace thermocouple

I take it this is a forced air heater,if so, ther is a relay and thermal switchs involved plus possible a sail switch in the fan housing, check circuits, oil fan motor bearings

There are basically three things that can go wrong with the Warm Morning .
Sensor shut off. There is a sensor button on the back of the unit with a wire going from it to the thermocouple. This sensor turns the heater off if the flue is blocked, however it will also shut the heater off if the wire contacts are dirty, or if the sensor has gone bad.
You can test this by bypassing the sensor. Disconnect the two wires from the sensor and reconnect them directly together. If the pilot stays on, your problem is here. Try cleaning the wire contacts first.
Pilot orifice. If the pilot flame is small and doesnt look healthy, the pilot orifice may need cleaning. The hole is very small and can get dirty. Disconnect the silver tube and clean with electrical parts cleaner. Never try to clean the hole with an object like a pin, you may damage it. You may have to slide out the burner unit to get at the silver tube. (Always shut off gas before disconnecting lines and after you reassemble, spray joints with soapywater and look for small bubbles which may indicate a gas leak. Dont use parts cleaner around an open flame.)

Thermocouple can go bad but this is not as common as the first two problems.

If it shuts off it may be a problem with the thermocouple which needs to reach a certain temp so that the heater knows it is lit to continue sending fuel and air. If this is not operating propoerly it can cause the problem you are describing. You can check if this is the case by testing for continuity across the disconnected thermocouple leads while holding a lighter on the thermocouple. At room temp you should not have continuity, when it heats up the circuit should close. If this is not happening it may be bad. You can further test (CAREFULLY) by jumping the thermocouple leads where they come back to the control board. If it continues to run that is your problem. Also make sure the thermocouple is aligned properly to get heated by the initial heat or it will never warm up enough to close the circuit and allow the heater to continue to run...

Hope that helps...