Water Heater will not stay lit with door closed

[doanshop]

Originally Posted by GolfingDave

What I saw that was odd was the blue poof of flame when it reignites. Out of curiosity I would want to watch what happens on initial start up when the heat kicks on. Have someone turn the temp up on the thermostat while watching. See if it has a poof on initial start up. If not then that must be from residual gas.

Even if no one comes up with derating it, I would bet that the orifice is a standard size. Find out what Suburban uses for a derated orifice and maybe swap it out and watch what happens. It is going to be a smaller orifice(verify by size stamped on it) so should not cause any harm. Check the btu's of a Suburban against yours. If the same you can try it. See what number is stamped on your orifice. Do not go bigger orifice, only smaller.

Here is a link to a chart to give you and idea of the btu by orifice size. Lower number means more btu output.

https://www.johnstonesupply.com/orifice-chart

Warning: Only do what you are comfortable with.

I thought we were talking about a water heater not a furnace.

[doanshop]

Have you tried blowing out the combustion chamber?

[GolfingDave]

Originally Posted by doanshop

I thought we were talking about a water heater not a furnace.

Was wondering what you were referring to?
Reread my post, should have said water heater switch and not thermostat.

Good Catch. I knew what I meant but no one else would.

[peekay17]

Originally Posted by doanshop

Have you tried blowing out the combustion chamber?

Yes, I have tried that. Thx.

[peekay17]

Just as an FYI for those following, I did submit an inquiry to Dometic in which they basically told me to bring the RV to a dealer for service. After stating other things that it might be such as propane pressure. Potentially I will get a manometer to check the pressure to see if it's too high (or potentially an orifice swap as GolfingDave suggested). I also stated to them that the last time I brought my trailer to a dealer they had my RV for ~4 months and returned it damaged with the issue still present so I'm not planning to go that route again!

I am considering simply adding some ventilation as one of the Winnebago forum posters suggested. Drill a hole near the bottom of the door/panel and cover it with something like this... https://www.amazon.com/gp/product/B0...F0AF4HZZ&psc=1

It just bothers me because I know plenty of other people probably do not have this issue with these WH's even though it seems quite a number of people do. I think I will certainly look at the gap, spacing and location of the thermocouple just to ensure that's not the issue.

By the way, thank you all for the help, much appreciated.

[TitanMike]

Originally Posted by peekay17

It just bothers me because I know plenty of other people probably do not have this issue with these WH's even though it seems quite a number of people do. I think I will certainly look at the gap, spacing and location of the thermocouple just to ensure that's not the issue.

By the way, thank you all for the help, much appreciated.

It's not unusual for some to have no issues and others do. When a factory builds an item they test it for proper operation, prepare installation instructions that are supposed to ensure proper operation, then sell the product to a another who installs it in their product.

Most times the product is installed AS THE MANUFACTURER SPECIFIED and sometimes THE INSTALLER KNOWS BETTER which might work. On a kinder tone some are just careless. If they don't allow for proper air circulation (like hinted at in the "Winnebago post with excess butyl tape, etc) people end up having mysterious problems.

Then again, it may be a design error that the factory hasn't discovered because many will see the problem (opening door eliminates the problem) and just fix it themselves by opening up some space at bottom of door (maybe a hinge adjustment? Hole with screen?) and if the factory doesn't see the issue with remedy, they just merrily go about their business saying "we don't really have a problem, it must be you".

FWIW, I'm one that will more often than not just fix the problem when I see it and save time and trouble. I developed that attitude after my 1995 trailer needed several months to schedule an appointment and get warranty repairs done. Most by tech's that had less skills than many high school kids.


In this case adding the 4" vent certainly looks like a viable solution. Might be necessary to modify the back so there is little metal extending into the heater compartment. Cut most of the metal that would secure this vent in a thicker door/wall/soffit down to just enough to center it in the hole and leave 4 or so tabs that can be bent down to secure.

Personally I think the design is faulty as it forces fresh, cool air, to enter right next to the burner exhaust which without perfect conditions will interfere with normal convection which seems to be the problem here.

A note re: some thoughts on RV Dealer Service Depts.

In almost all parts of the country RV use is seasonal. Around here the majority of people will use them from April/May to Sept/Oct as very few NF, and State campgrounds are open. Weather is also not conducive to camping so RV's are put in storage for 6-8 months. This leads to less potential work for the dealer's service dept and they pare their staff down to a bare minimum. Come the travel season and an uptick of work in the shop they add some staff but often with limited skills. It's no wonder why scheduling times are extended and quality of work often questionable or just downright shoddy.

Auto dealerships are much more "year-round" in their service departments and as such they attract more quality tech's which are able to work year-round rather than "seasonal".

[TitanMike]

Originally Posted by peekay17

It just bothers me because I know plenty of other people probably do not have this issue with these WH's even though it seems quite a number of people do. I think I will certainly look at the gap, spacing and location of the thermocouple just to ensure that's not the issue.

By the way, thank you all for the help, much appreciated.

It's not unusual for some to have no issues and others do. When a factory builds an item they test it for proper operation, prepare installation instructions that are supposed to ensure proper operation, then sell the product to a another who installs it in their product.

Most times the product is installed AS THE MANUFACTURER SPECIFIED and sometimes THE INSTALLER KNOWS BETTER which might work. Then again if they don't allow for proper air circulation (like hinted at in the "Winnebago post with excess butyl tape, etc", people end up having mysterious problems.

Then again, it may be a design error that the factory hasn't discovered because many will see the problem (opening door eliminates the problem) and just fix it themselves by opening up some space at bottom of door (maybe a hinge adjustment? Hole with screen?) and if the factory doesn't see the issue with remedy, they just merrily go about their business saying "we don't really have a problem, it must be you".

FWIW, I'm one that will more often than not just fix the problem when I see it and save time and trouble. I developed that attitude after my 1995 trailer needed several months to schedule an appointment and get warranty repairs done. Most by tech's that had less skills than many high school kids.


In this case adding the 4" vent certainly looks like a viable solution. Might be necessary to modify the back so there is little metal extending into the heater compartment. Cut most of the metal that would secure this vent in a thicker door/wall/soffit down to just enough to center it in the hole and leave 4 or so tabs that can be bent down to secure.

Personally I think the design is faulty as it forces fresh, cool air, to enter right next to the burner exhaust which without perfect conditions will interfere with normal convection which seems to be the problem here.

I just looked at my Suburban W/H cover and it clearly has a separate louvered air intake, not integrated into the same opening as the exhaust but to the left, separated by a couple inches, and almost as large as the exhaust.

As I said, probably a design issue that makes the unit sensitive to installation error.

[Thearcher01]

I took my new trailer to Colorado on vacation and had a lot of trouble with the furnace. A lady at Suburban furnace told me it would be fine once got back below 5000 feet. She was correct. Propen flows differently at altitude. Combine that with less oxygen and you have to change orifices and adjust air. I just put up with it.

[champ837]

Until the pressure is checked and verified to be at or very near 11 inches of water column I think you're spinning your wheels.


Another indication of incorrect pressure would be to check the flame on a burner on the stove. If it is larger than what would seem normal you may have pressure that is to high.

[Indigo Yogi]

Hi,
I had the same issue with our new Rockwood a few years ago. I can’t remember which wire but it was one that was touching the door when closed. Pushed the tab connector with the wire attached away from the door. Has worked fine ever since. If the trailer wasn’t over fours away I would’ve taken a photo. Good luck 👍

[Dirthawg_]

I had a suburban water heater that acted similarly. It would run fine with the door open but would have issue igniting with the door closed. I used it that way for 2 years until I finally figured out the problem.

The problem was the thermal couple was not directly in the center of the pilot flame. It was in the flame but slightly to one side. I used a set of pliers to very carefully bend the thermocouple to the very center of the flame and my problem went away.

I mention this only as advice since I had a different brand and a slightly different issue but it certainly something worth checking into.

I also understand that if the thermocouple doesn't detect a flame it shuts the gas off which could be why your is flaming out. Possibly the open door allows the flame to hit the thermocouple just right to stay lit.

[EdsIrv2]

Interestingly I had the same issue and it cost less than 20 cents to fix the issue. When my door was shut it would start up and then quickly shut down. It turned out it was not getting enough oxygen - as many have already pointed out. To fix my issue, I used two electrical ring connectors - one for each side. I unscrewed the screws holding the heater in, put the ring connector on and screwed it back in. I then bent them slightly to allow more air to enter. Problem solved.

[Scottnweeze]

[QUOTE=TitanMike;2835214]After watching the video two thoughts come to mind:
...

*a variation of the above, the flame may not be hitting the thermocouple that keeps the gas solenoid open. Door closed alters the amount of flame impinging on the thermocouple. Check it's position and see if it's support is possibly bent. Does it look like it would be well heated by the flame?


The same issue happened to me, wouldn't stay lit without the door open. I thought it was due to altitude, we live at 7000ft. and are usually camping at 9K or 10K ft. BUT I adjusted the thermocouple as TM suggested and that solved the problem. Specs were easy to find online for my model, and it was a simple job.

[TitanMike]

Originally Posted by champ837

Until the pressure is checked and verified to be at or very near 11 inches of water column I think you're spinning your wheels.

Interesting, but the pressure is the same, door open or door closed.