Suburban sw6d hot water heater

Old-Biscuit wrote:

09FLSTC wrote:

powderman426 wrote:
Firstly, it's a water heater. We don't need to heat hot water. If it's sparking and igniting you probably have good voltage. Its most likely going out because the thermocouple is either bad or out of position.

It is also a hot water heater because the water is often still hot when it lights to maintain temperature when cooler water is introduced but we know how people love to insert cleverness, lol but you are also correct that it's most likely the thermocouple :)

Doesn't use a 'thermocouple'

Then square him away.

09FLSTC wrote:

powderman426 wrote:
Firstly, it's a water heater. We don't need to heat hot water. If it's sparking and igniting you probably have good voltage. Its most likely going out because the thermocouple is either bad or out of position.

It is also a hot water heater because the water is often still hot when it lights to maintain temperature when cooler water is introduced but we know how people love to insert cleverness, lol but you are also correct that it's most likely the thermocouple :)

Doesn't use a 'thermocouple'

powderman426 wrote:
Firstly, it's a water heater. We don't need to heat hot water. If it's sparking and igniting you probably have good voltage. Its most likely going out because the thermocouple is either bad or out of position.

It is also a hot water heater because the water is often still hot when it lights to maintain temperature when cooler water is introduced but we know how people love to insert cleverness, lol but you are also correct that it's most likely the thermocouple :)

Thanks to all.

THIS is the spark electrode (and flame sensor)

Has to be directly in main flame...engulfed

When main flame is lit..a milivolt signal is generated thru 'flame ionization'. Signal goes back to circuit board 'proving' main flame lit off. If circuit board doesn't get signal....DC power to gas valve is dropped.

Doesn't take much to impede milivolt signal....
Dirty electrode
Electrode not in main flame
electrode ceramic cracked..signal goes to ground
wire from electrode to board...dirty/loose connections

Hopefully it is problem with electrode and not signal track on board.....new board

Go to Chris Bryant's Site and get the Service Manual.

I think you'll find that this heater uses Flame Sensing. If so, the same element that the ignition spark jumps from is also the Sensor. It's pretty scientific and I'm not so I can say that it senses Ionization... That is different from the old Thermocouple scheme.

If the Flame Sensor is out of place or perhaps even dirty, it'll not realize a flame is burning. It's doing re-light attempts and only does X number of those before giving up till you cycle the On/Off switch.

Manual will tell all.

clean the sensor

Yes, it tries to restart time after time but with same results. Ignition , flame ,shutdown after ignition,flame shutdown. When flame is burning, it is a really good lookin flame. Nice and blue. What does sensor look like and where is is the flame sensor ?????
thanks

Firstly, it's a water heater. We don't need to heat hot water. If it's sparking and igniting you probably have good voltage. Its most likely going out because the thermocouple is either bad or out of position.

dose it try to relight after the 15-20 sec.? you don't have a voltage problem or it would not lite at all.sounds like it is not sensing the flame and shutting down the gas valve.