How to clean Atwood Water Heater Burner Tube?

[D44]

Water heater would not fire up on our last trip. Checked with a multimeter and the thermo cutoff fuse had blown. Replaced it and tried again. Heater tried to ignite but flames were burning at the air intake and melted the replacement fuse.

I think my next step is to try to clean out the burner tube but I can’t seem to get the brush in through the air intake slots and the collar doesn’t move to the right enough to disengage from the gas nozzle to go through the open end.

Do i have to remove the entire tube (looks like 4 screws and the wire to the ignitor) or is there a different way to clean out the tube while it is in place. Only have one more cutoff fuse so want to try cleaning before firing up again.

Thanks,

Walt

[GCinSC2]

Suggest pulling burner as you surmised.

Critters?

[D44]

Hoping there’s a spider web or a little something in there causing the problem. If not, I’ve exhausted my limited troubleshooting skills. And burned up my last thermo fuse that I have on hand . . .

[GCinSC2]

Compressed air and or vacuum may assist.

Thermo fuse did it’s job.

[D44]

Good idea for the compressed air - I’ll see if I can get a nozzle for my Viair compressor and give that a shot before unscrewing the entire assembly. Is there anything in there that I have to worry about blowing out of alignment before I give it a few blasts from the compressor?

[CoorsLite]

I recently went through the same experience. After replacing the thermal fuse I pulled the whole burner tube assembly out (held with small sheet metal screws). When I looked inside the tube it was completely plugged with a spider’s nest. I used a brush to push everything out. It is now my understanding you can just slide the small adjustable air mixture cap out of the way and push a flexible brush through there. I’d mark the location of the air mixture cap before I started. Lastly - I doused everything with SpiderBan - we will see if that helps.

[cazual6]

This was not my post, so I can't share the video directly. Admins may not allow me to post this link, but here is what someone did to fix it.


https://www.facebook.com/groups/AirstreamAddictsforAdults/permalink/2467993080089771/

[GCinSC2]

D44

Any update on solution?

Gary

[ROBERT CROSS]

Originally Posted by D44

Good idea for the compressed air - I’ll see if I can get a nozzle for my Viair compressor and give that a shot before unscrewing the entire assembly. Is there anything in there that I have to worry about blowing out of alignment before I give it a few blasts from the compressor?

I would do the 4 screw thing and ck for critters.
While your at it ck the gas orifice in brass fitting.
Do NOT put anything in the hole, use a solvent and blow it out with air.
Look in the big end for a teeny tiny light at the other end.

Bob
🇺🇸

[D44]

Originally Posted by GCinSC2

D44

Any update on solution?

Gary

I wiped the nozzle down with alcohol on a q-tip. I opened the air intake as much as I could and blew compressed air though the burner tube and could tell it was coming through into the flue. Hooked up my last thermal cutoff and fired it up.

Flame still was at the air intake and melted the last fuse.

With 3 weekends of camping coming starting next week I broke down and went for the Amex fix - called my local place and brought it in for them to fix.

[bweybright]

Originally Posted by ROBERT CROSS

I would do the 4 screw thing and ck for critters.
While your at it ck the gas orifice in brass fitting.
Do NOT put anything in the hole, use a solvent and blow it out with air.
Look in the big end for a teeny tiny light at the other end.

Bob
����

When you say solvent I am wondering what you recommend? I have Acetone, Toluene, and alcohol 99% down to 70 % I could use. All are solvents but with different use and application conditions? I am not sure what you are suggesting to use as I have access to any of the above? So please let me know what you have used so I can add it to my maintenance library.
I have successfully used air at 120 psi through an air gun to blow garbage out of the burner...but never had to deal with cleaning the burner itself out with a solvent.
Thanks.

[BayouBiker]

An automotive brake cleaner would be most effective. Engine degreaser or WD40 would work in a pinch but you'd have to wipe it dry.

[ROBERT CROSS]

I've used this. at home. Spray into a glass container and let sit for 2-3 hrs.

We used Blaster in the parts cleaner at the Chevy Store.

Bob
🇺🇸

[eubank]

Yep, pretty sure sign of being stopped up. Probably a very nice spider nest in there, a big one. I, too, use brake parts cleaner for this kind of job. And for quick drying thereafter, some canned air.

Recently, I restarted all systems in our vintage rig and found stop-ups in both the water heater and the refrigerator propane. Both of those were in the far, FAR smaller orifices, main burner in the fridge and pilot in the water heater. As with your appliance, flame was coming out of the very small fresh air feed for the water heater pilot. Took them apart, sprayed clean, dried, reassembled, all good. (If you take apart the burner assembly in the fridge, be very careful. Very small parts! Easily dropped and impossible to find!)


Lynn

[85MH325]

Go to a craft store and buy some foot-long pipe cleaners. They're quite handy, and about 80% of the time will clear the web without disassembling the burner.

However if you need to take the burner off, it's usually (depending on the age and model of the WH) about four screws that have a 5/16" socket head. Once the burner is off, you can even use a twig to clear the burner tube. Re-install the way it came out.

DO NOT change the air/fuel mixture adjustment that is set at the factory. It'll lead to burner woes.

Thirty second job with a pipe cleaner, a ten minute job without. I've cleaned many of them for folks at rallies over the years.

[blkmagikca]

Any time my water heater thermal cutoff blew the cause had been a blockage due to a spiders web. A gas tech told me to blow out the obstruction with compressed air. The first time I did that I got a faceful of spiders web, so subsequent times I always made sure I was not "in the line of fire".

[ewhitney45]

There are a number of detailed, useful videos on youtube that provide detailed how to's on cleaning up the water heater. Strongly recommend, just do an Atwood Water Heater search.

[Halford1]

After cleaning out the tube... add a metal screen in back of the heater door to prevent any future wasp nests, big spider webs and etc... I have yet to do that even though I did it in my previous popup.

[blkmagikca]

Another way to clean a blockage caused by spider webs is to use a propane blow torch. Direct the flame into the the bottom of the tube, and it will totally melt the spider web. On a unit caravan to Bozeman MT, one of the rigs was unable to get his water heater to work. I had a propane torch and lent it to him - 30 seconds later the obstruction was gone and the water heater worked. I should add that his rig was a 1956 which fired using a pilot light.

[senjohn]

I fought this problem for two months. I first cleaned everything. Then I thought the valve wasn't opening enough so I purchased a new valve. I could get the flame to remain where it needed to be if I choked almost all of the air off on the tube, but that was intermittent and didn't give me proper flame. Finally, I purchased a new orifice assembly and a burner tube. That finally fixed it! Now I know the old orifice was clean enough because I had it out three times. I suspect the problem was that too much air was coming in between the burner tube and the orifice assembly and the new tube gave a tighter fit. Anyway, I scoured the forums for answers but this is what finally resolved my issue.