Hot water heater not lighting up

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
CDN_Taxman

CDN_Taxman

Well-known member
Joined
Jun 7, 2010
Posts
230
We've been full timing during a renovation since the end of March.

Our hot water heater (about 8 years old) has worked as it always has without issue until the past week.

There is no hot water......

If we turn the switch in the bathroom off, it does try to fire up.....but fails.

There is plenty of propane, so that's not it either.

I checked if from the outside and there's a little black rubber thing that says press to reset.....not sure what this is or how it works. Pressed one side and seemed to work.....pressed the other side and it seemed to be stuck or broken.

Finally, there is an on/off switch that has been set to off since we moved in (I forgot to turn it on!). Turned it on and nothing happened either.

Suggestions would be greatly appreciated.
 
What heater brand & model?  It helps to know what we are dealing with!

The On/Off switch is probably for 120v electric heating.

Please elaborate on "it does try to fire up.....but fails". You hear the igniter clicking?  Repeated cycles?  Does the flame light and go out, or simply never light?  Open the outside cover and watch the burner tube while somebody else flips the inside switch.
 
If you have a dual source system and it doesn't seem to be working with propane, try the 120V side.
As Gary mentioned, the On/Off switch is for the 120V heating. Turn it on and then see if there is another 110V switch inside the coach for turning on the 110V heat side of the water heater.
Ours is set up that way. I can select gas heat or 110V heat. I just have to remember to turn on the 120V switch that is on the WH before using the 110V heat.
Be darn sure the WH is full of water before turning on the 110V heat or you will burn out the heating element.
 
Don't have the model yet but will.....figured out the electric switch after posting this. Where would the inside switch be? And yes, its full of water.....has been working fine for five months right now.

Checked with the boss and still no hot water.

RE: propane.....tries to fire up means we hear the clicking and the heater fails to light with propane. I was looking at it last night and no flame at all.

When I open the cupboard in the trailer that has the tank, there's a ringing sound that I hear that wasn't there before.


 
OK, igniter clicks but burner doesn't light. Next step is to verify that the gas valve opens and you have propane flow at the burner. Could be as simple as a bug next or rust flakes in the burner tube, or as bad as a failed gas solenoid. Even that is easy enough to replace, though.
You didn't state Atwood vs Suburban heater, but you can get an Atwood service manual at http://bryantrv.com/docs2/docs/atwoodwaterheater.pdf
Suburban manual at http://bryantrv.com/docs2/docs/subsw.pdf
 
The most common problem for gas water heaters is spider webs in the gas path.  They seem to love the smell of propane.  The tiniest little thing in the jet/orifice is all it takes to stop ignition.  Fairly easy to disassemble and clean.  I use rubbing alcohol and sometimes a guitar string to clean the orifice.

Are you getting a spark?  Can you see it?  If not the problem is likely to be a corroded connection.  Simply removing the spade connectors and pushing them back on will usually fix it.
 
Thanks for all the help. I did post an update last night that didn't seem to post.

Suburban SW6GE. I think my propane reset is off or broken....trying to get a screw off to take it apart but the gas lines are in the way!

Finally if I go into the cupboard where the tank is, there's a plastic cover where the wires go into that is making a ringing sound.
 
CDN_Taxman said:
Finally if I go into the cupboard where the tank is, there's a plastic cover where the wires go into that is making a ringing sound.
Click to expand...
Make sure that if you remove that cover that the power is off. Unplug the RV from the power source.
 
I simply flipped the breaker on the panel to make sure it was off.
 
ok, Suburban sometimes has an external control board that can be mounted nearly anywhere but it's usually near the tank.  The board is attached to an edge connector and has a habit of coming loose. 

Follow the wires from the control panel.

On our last towable the board was stuck to the top of the tank insulation with double sided tape.  Double sided tape doesn't stick to styrofoam for long.  I stuck it somewhere else with a tie wrap and used another to hold the board in the connector.
 
OK....

I cleaned out the gas tube....there was nothing in it!

I took off what I think was the external control board. Found the plug on the bottom that I think was loose. However when working with it, a big round part on the control board came off....I may have broken it.

After turning the propane switch on now, there's no more clicking sound....more evidence I may have broke the control board?

Or, alternatively, I think my propane reset is pooched. Instead of seeing the nice clean rubber cover, there's a round plastic piece sticking out of that.

I'd attach pictures, but there on my phone and too big for this site.

 
It has a wire that connects the control board....thanks for the input. Is it supposed to be fused to the control board or is it supposed to come off and on easily?
 
Went into an RV store and yes, the big round piece isn't supposed to come off like that.

Just got a new control board and will try and put it in tonight.....fingers crossed!

Mike
 
An update......

Swapped out the control panel and now the heater attempts to light once again.

Still no success, so it's either the igniter or the propane feed. Seeing how the propane was working all summer, I don't think that's it.....so its the igniter next.


 
You should be able to see & hear the igniter as it sparks. If it does that, you don't need a new one. It might have got out of position a bit, though that too is rare on a water heater. However, it is very sensitive to the flow of the gas/air mixture and a few rust flakes or cobwebs can disrupt it enough so that it doesn't light well. A proper mixture of air and propane has to flow right over the electrode for it to work reliably.
 
I cleaned out the gas tube and there was rust in it. I cleaned out the chamber beyond the ignitor as was. Lots of rust in it.

I can hear the clicking but could not see it at all......so I'm thinking that's the problem.
 
Are you sure you're getting gas flow?  Rust beyond the burner is probably not the problem.

I don't recommend this for just anybody because it can be dangerous.  It IS dangerous!

Remove the burner tube.
Remove the orifice/jet.
disconnect the igniter!  (very important!  If you skip this you might have a fire)
power the WH on. (and be ready to turn it off)
The gas valve should open for a second or two.  If it does you will feel and smell the propane flow.  If you don't you probably have a bad gas valve or a blockage before the orifice.  (I've never seen the latter but it's a crazy world)  I guess you could also have a bad electrical connection to the gas valve but you would probably have checked that by now.

Don't assume that the orifice and tube are clear because you can see through them.  As Gary (Resident RV Wizard Emeritus) said, it doesn't take much.  Run a bottle brush or something through the tube.  They don't recommend sticking anything through the orifice/jet but I've found several situations where it's the only thing that worked.

 
Still figuring things out.....a bad starter wire is the next scenario.

While it could be a gas problem, we've been using it since April with no issues....no not highly likely!

Mike
 
You must log in or register to reply here.

Latest posts

Members online

Total: 1,110 (members: 27, guests: 1,083)

Forum statistics

Threads
131,933
Posts
1,387,732
Members
137,683
Latest member
chaderic
Back
Top Bottom