Suburban SW6P Water Heater Intermittent Flame Out on Start

[htgrimmi]

I have a 2007 Gulfstream Amerilite 25BH with a Suburban SW6P water heater that will intermittently flame out on startup. Here are some notes and observations.

-The pilot light is nice and blue and covers the tip of the thermocoupler.
-I can run the pilot light for weeks and it won't go out.
-Propane tanks are new, full and this occurs with other tanks.
-The water heater is the farthest propane device from the tanks. Opposite ends of the trailer.
-Stove, oven, fridge and heater work fine.
-When operating, the heater flame is strong and blue with that distinctive roar noise.
-There is a bit of a hard bend in the propane line with a hint of a crease but that has been that way since purchase. This condition has only recently occurred.

What I have seen happen, when the pilot light goes out is I hear a louder whoosh, for lack of a better term and a flash of orange flame out of the cover.

When I drop the cover, in a no wind situation, the flash comes from all over the face of the water heater and is more orange. Also if this makes any sense, the hiss from burner is much quieter. It is almost as if the gas valve is not opening completely and the gas doesn't have enough pressure to go down the burner tube and ignite properly.

Now when it works properly, the hiss is much more pronounced from the burner before it ignites, the whoosh is much quieter and I've only seen a little flash of blue come up out of the flue. No giant orange flame all around the front of the unit.

There was one case that I observed where the initial startup was ok but the burner flame was very weak. It kind of sputtered and squeaked for a lack of a better description and about 15-30 seconds later the condition cleared and the burner flame turned blue and with the normal roar.

I initially cranked up the pilot light adjustment with change in behavior.

I've also confirmed the burner tube is clear. No spider webs, mud dauber nests, etc.

Any thoughts, comments, tips on this would be appreciated although I'm guessing the answer is the gas valve $$ or just bite the bullet and replace the whole water heater as it's only a few bucks more.

[htgrimmi]

Hello Jean,
Thanks for the feedback, I'm glad it all worked out!
All the best.

[borderbrae]

Hank, I've had the same problem with the HWH in my Casita trailer for quite a while and decided it was time to try to fix it. I did lots of searching and found this thread. Then I went to your Facebook page with the step by step photos and info. I studied it and ordered the pilot burner igniter and then studied the photos some more. I had a lot of trouble removing one of the large bolts, finally had to cut it off, but once that was done the rest was easy. Now when I light the HWH it fired up immediately with no flashback/explosion. What a relief! Thanks so much for taking the time to take & post the photos along with all the step by step info.

[htgrimmi]

I know it has been a year but I wanted to follow up on this post for future readers.

It looks like the thermocoupler was flaky. I was getting ready to replace the whole water heater but found a seller on Amazon that had pilot burner/thermocoupler assembly on sale for 17.00 so I figured it was worth a try.

I also noticed a lot of white corrosion on the fitting from the thermocoupler that goes into the gas valve on old part. So I cleaned out the hole in the gas valve with a q-tip till no more white residue came out and replaced the old assembly with the new one.

Zero flame outs in three days with a family of 5 using it. Also note I set the thermostat on the gas unit lower than the electric heating rod in hopes of some slightly lower propane use.

Here is a link to the photos.

Suburban SW6P Pilot Burner Assembly Replacement

[htgrimmi]

I got the trailer home from camp and decided to stick with using the little electric kit versus fixing the gas valve. It worked so well for us and we are hoping to upgrade to a larger trailer in the next year that it just doesn't make sense to drop the cash for a new valve or heater.

Here is a link to the install pictures via a public FB album.

1000W Electric Water Heater Kit Install

[htgrimmi]

Since the trailer is up at camp for the summer, I decided to go with the Hott Rod electric kit. A guy on ebay, seller name rvtoyboys is selling the Hott Rod kits with the name cut off the packaging for 70.00 and free shipping.

I ordered the 10 gallon, 625 watt unit and he exchanged the atwood bushing for a suburban bushing with an anode. Kit normally comes with both bushings but no anode.

Install was a piece of cake but at the moment, with it being up at camp, I have it wired up using a 3 prong extension cord to an outside plug. Once I drag it back from camp, I will wire it up internally with a switch and indicator light.

To say I'm thrilled would be an understatement. It obviously takes longer to heat up and recover than propane but I turned up the t-stat to about 135 and it was able to give 2 adults and 3 kids nice warm/hot showers. We are pretty good at doing stop/start showers, turning the hot on only enough to get some flow and control the temp with the cold. If that makes sense.

And obviously it is much better than no hot water. Not to mention much cheaper than a gas valve or replacement water heater.

Only had one strange issue. The water heater door faces the afternoon sun and it is hot, really hot down here, 94+ today. So the water heater door was baking in the sun and it looks like this kept the t-stat from detecting the temp had reduced on the pressure relief valve. This left me with lukewarm water. Once shade hit the cabinet, I had nice hot water in about a half hour. This wasn't a major crisis as no one wants to shower, cook or do anything but sit in the pool at the campground during peak heat. I'm going to look at adding some water pipe insulation and leaving an opening for the pressure valve for safety.

Granted this is not a 100% replacement for a propane or real propane/electric unit but I'd give this kit a solid B+ for effort and an A+ for expense.

[htgrimmi]

Correct, it is a propane only unit.

It really appears to be a gas valve issue. Sometimes it comes on fine, other time the initial hiss from the gas is very faint and I get the flame out.

I'm leaning heavily to putting in the 10 gallon lightning rod 625w unit and going electric.

[Ex-Tech]

htgrimmi wrote:
Thanks so much, will go through it again this weekend.

I also went through all the grounds and connections last year. Huge improvement. Lights don't dim as more get powered on.

Where can I find instructions on removing the main orifice?

Found this http://dutchmen.com/image/data/documents/parts/Suburban_Water_Heater_Service_Manual.pdf One comment in the doc talks about flashback and low pressure.

Grounds and connections? If you have a standing pilot model as you stated in your original post, what ground and connections are there? Usually the standing pilot light models don't have electrical components. Just curious.

[htgrimmi]

No major news from this weekend of camping. I did adjust the pressure regulator up by 1/4 turn but really did not want to mess with it without taking a reading with a manometer.

One thing I noticed is that the unit would not flame out when I had the water heater door open. No need to chime in here with the dangerous comments, I know this.

What I did this weekend was to set the t-stat on the water heater to high, light it, close the door and have everyone take showers back to back. Worked well but not really a good solution.

Was doing some more research and came across those Hott Rod electric conversion kits. We never camp without hookups and I have a 110V circuit sitting in the same compartment as the water heater. The unit was a trade show demo and Gulfstream mounted a TV and DVD in the compartment next to the water heater. The Hott Rod kit says it uses only 400 watts.

Has anyone tried one of these? I'm looking at keeping this trailer for another 6-9 months and would like to avoid buying a new water heater.

http://www.adventurerv.net/hott-rod-electric-conversion-gallon-water-heaters-universal-p-1163.html $84.99

[Old-Biscuit]

To remove orifice.....pull burner tube off, unscrew orifice from end

Yes low lp pressure can cause improper flame , flame at air shutter etc.

But you stated ALL other LP appliances work properly.

So if after cleaning everything you still have main flame problem then the gas valve may be failing.

[htgrimmi]

Thanks so much, will go through it again this weekend.

I also went through all the grounds and connections last year. Huge improvement. Lights don't dim as more get powered on.

Where can I find instructions on removing the main orifice?

Found this http://dutchmen.com/image/data/documents/parts/Suburban_Water_Heater_Service_Manual.pdf One comment in the doc talks about flashback and low pressure.

[Old-Biscuit]

Simple manometer........




But first...

Pull burner tube and clean it out with a bottle brush
Clean out the combustion/exhaust chamber.....run a wire thru then attach rag and pull rag back out
Remove main orifice and clean with alcohol
Clean thermocouple with some emery cloth
Clean/tighten grounds

Doing the above will go a long way to 'fixing' poor flame conditions.

Things as small as spider webs will disrupt a good flame

[htgrimmi]

Ok, sounds like it is time to make a manometer and or for 40 bucks on ebay I can start by replacing the regulator. Still less expensive than going to a shop.

Burner tube is clear, no soot buildup either.

I might adjust the current regulator up slightly, in the interim, as a test.

It is parked at camp for the summer and I'd like to avoid a weekend remote service call.

[beemerphile1]

When was the last time it was serviced? Sounds like a burner and flame tube cleaning is called for.

[GASMAN6674]

Sounds like delayed ignition. Could be pilot out of posistion or sluggish gas valve.
Once you have verified the inlet pressure in static off mode (11-11.5"wc)and with unit burning (10.8" wc or so) and pilot posistion replace the gas valve