# Water Heater Wont Stay Lit



## markc732 (Aug 22, 2011)

i have a 2005 ob 28rss i put the switch for the hot water heater to propane and it lights only when the spark ignighter is sparking then go's out when it stops sparking it does that 3 times then go's into flame failure does anyone have any ideas


----------



## CamperAndy (Aug 26, 2004)

The thermocouple is not sensing the flame is the most likely issue.

Watch it is it lights and make sure the tip of the thermocouple is actually in the flame. If it is then is could be a bad thermocouple. The thermocouple is about a $10 item and something a handy person can replace. Also make sure you have a robust blue flame, if it is weak or yellow/orange then you may have a low gas flow that will also make it harder for the thermocouple to sense the flame.

Also disconnect all the connectors from the control board and clean them to improve the contact. The fact that you are getting flame, even for a short duration, tends to rule out the control board.

Have you tested it on electric only? If it works on AC then the control board again is most likely okay.


----------



## KTMRacer (Jun 28, 2010)

CamperAndy said:


> The thermocouple is not sensing the flame is the most likely issue.
> 
> Watch it is it lights and make sure the tip of the thermocouple is actually in the flame. If it is then is could be a bad thermocouple. The thermocouple is about a $10 item and something a handy person can replace. Also make sure you have a robust blue flame, if it is weak or yellow/orange then you may have a low gas flow that will also make it harder for the thermocouple to sense the flame.
> 
> ...


try blowing out the open propane air channel tube with air pressure. I've had a few times when a cobweb or dust got into the tube and likely the jet. result was not enough propane flow for a good clean flame. It could be in your case just enough propane is getting through to barely give a flame, not enough to heat the thermocouple. In my cases i got a sooty flame, once I blew it out, everything was fine again.


----------



## Gr8daggett (Oct 19, 2011)

Happened to me once in the Spring when I forgot to open up the bypass valve. Seems it didn't work well without water in the heater.


----------

