Cold blooded hot water heater?

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thelazyl

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Nov 9, 2018
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488
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Molalla, Oregon
Hello!
We're on our first trip of the year. At our first campsite .. started up the hot water heater last night and things were fine. This morning the fault light was on - heater was off. I checked connections and turned back on. It took 2 cycles for the propane to light. When it came on the gas burn was sporadic - sort of like what a cold blooded car sounds like when first starting. I assume this is air in the line and a temporary condition? The unit was last used a few months ago during ice storms - we didn't have power for 12 days. Have a full tank of propane. Coincidentally our Norcold fridge isn't working - however the NO CO error returned and I think the cooling unit has finally failed. I don't think this is related to the hot water heater.
I'd appreciate any thoughts ..
Thanks,
Mark
 

Rene T

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May 20, 2011
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Farmington NH
I would start by removing the burn tube to make sure that bugs didn’t move in. When it’s burning, are you getting a nice blue flame with practically no yellow flame? If you’re hgetting a nice blue flame them bugs aren’t the problem.
 

Gary RV_Wizard

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Feb 2, 2005
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At our Silver Springs FL home
Agree with Rene - the most likely culprit is the air/gas mixer in the inlet tube or the burner area itself. Cobwebs, rust, whatever.

Run the gas stove to verify that gas delivery is ok. Then try the gas furnace as well.
 

Kirk

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Oct 30, 2005
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Full-time , Escapee
Your water heater uses a probe to supply the spark to ignite the propane and it also senses the heat of the flame when it ignites. It is very common for that probe to fail to detect the heat and need to be replaced. You can easily troubleshoot this by having someone inside turn on the water heater while you stay outside with the access panel open and watch the burner area, to see what happens. If it sparks and the gas ignites but the probe continues to spark several times and then shuts off, you have found the problem and that probe will need to be replaced. Some people clean the probe and gap it, and that usually does work for a short time but in my experience it is best to replace it as soon as possible because the problem will return.

If the flame fails to burn it could well be the burner tube but probably isn't since you successfully had it burning earlier.
 

NY_Dutch

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Nov 22, 2010
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Where our wheels take us!
One quick try that sometimes corrects a flame sense problem is simply to disconnect the ignitor wire at the board and reconnect it a few times to clean off any corrosion. The flame sensor works at millivolt levels, and it takes very little resistance cause a detection failure.
 

John From Detroit

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Apr 12, 2005
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24,615
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Davison Michigan
I keep hearing "Air in the line" "Air in the line" But unless you remove the tanks (in which case the pigtail from the tank to the regulator can bleed out and get filled with air if they are off long enough.. but when it comes to a load like the water heater you'd never notice that tiny bit of air) once the system is purged. normally at the dealer BEFORE you show up to take possession.... HOW is air going to get in the lines?

NOTE: I grew up with propane In the house. The Milkhouse and a 2nd house.
All 100 pound bottles (multiple bottles per building) and never once did we suffer air in the lines.
 

Ray-IN

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Mar 16, 2014
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186
Location
North America-somewhere
One quick try that sometimes corrects a flame sense problem is simply to disconnect the ignitor wire at the board and reconnect it a few times to clean off any corrosion. The flame sensor works at millivolt levels, and it takes very little resistance cause a detection failure.
My heater did that, it was the gang plug on the control board terminals corroded from non-use. Polished each one with a pencil eraser, problem solved.
 

thelazyl

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Nov 9, 2018
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488
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Molalla, Oregon
Update - I solved this one! There was a small bug / spider nest thing in the burner tube. I pulled it apart and used a shop vac to suck it out. I am back in business!

Thanks everyone!

I joke with my DW that, when I fix things on my own, I act like I just invented fire (regardless of how simple the fix was). In this case I kind of did that.
 

edjunior

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Apr 12, 2005
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2,525
Location
Roman Forest, TX.
Update - I solved this one! There was a small bug / spider nest thing in the burner tube. I pulled it apart and used a shop vac to suck it out. I am back in business!

Thanks everyone!

I joke with my DW that, when I fix things on my own, I act like I just invented fire (regardless of how simple the fix was). In this case I kind of did that.
I'm kinda like that also. Hey, we gotta milk it when we can, right??

Great you got it fixed cheaply. My heater stopped working on my old TT, and I took it to a shop. Cost about $300 to clean the dirt daubers off the burner. Something I could have done in about a six pack or so. Oh well, we live and we learn!
 
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