Hot Water Heater Exhaust Damage

[Road Ruler]

Hello Folks;

Since lighting up my hot water heater for the first time we noticed black smoke residue on the side of the trailer after 4 days of use.

Has anyone experienced a problem like this. Any ideas???

Note... I also have to hold the pilot knob on for about 5 minutes before it will stay lit without going out.

Thanks Note.... See pic in next post.

[Road Ruler]

Photo

[overlander64]

Greetings Wayne!

You have a familiar site for me - - it is typically caused on my coach when a spider chooses to build its nest in the air supply tube for the water heater. The repair is to take the tube off (tube that runs across the front of the water heater) and clean it out with a soft bristle bottle brush of the appropriate size. This has happened at least three times on my coach this season - - each time that is sat for more than two weeks between trips. I believe that this causes the air/fuel mixture to become too rich which results in the sooting, and I also believe that someone told me that it also invites problems with carbon monoxide.

Kevin

[Road Ruler]

Hi Kevin;

What you are saying does make a lot of sense. If not enough air is getting through it would run rich. Will check the tube for spiders in the next couple of days and update.

Thanks

[john hd]

mine had the same problem, spider nest in the air tube.

the black soot will clean right off.

you will notice a differance in the way it sounds after you get it cleaned out. you can use this as a clue in the future as to its performance.

john

[smily]

I had to replace my venturi tube with new one because it had little "pin holes" in it.

I could not tell that they were there until I removed it. I replaced with new Stasinless Steel tube and you can definitely tell the difference.

I have to hold my pilot light button for quite some time too but I assume that it takes a little while for the gas pressure to build up from the front of the trailer and also the Thermocouple has to get hot to keep the gas supply flowing.

I hold my lighter stick directly under the thermocouple and this seems to expedite the process.

Smily

[Pahaska]

Even after you purge the lines to the water heater, it takes a long time to fill the tube to the pilot with gas because the pilot orifice is so small.

One way around this is to get the thermocouple good and hot with your lighter an then turn the WH full on while keeping the thermocouple hot. The WH will light almost immediately, even though the pilot did not light yet because the main burner orifice is large and it purges very quickly. By the time the water is hot, the tube to the pilot will be purged of air and the pilot will light off of the main flame.

This has worked for me in three different trailers now.

[JPAIRSTREAM]

Wayne:

This problem indeed stand from not having enough air flow mixed in.

1. check for spiders as suggested or any blockage in this tube.

2. you can adjust this tube by loosening the little nut screw on breather and moving it to allow more air to be sucked in. You will here the flame roar in the tube with a nice blue flame. Thiswill give you optimal performance.

todays water heaters do not have a pilot light they have electronic ignitions. not sure what your has if it is a 73, depends if it has been changed.

[tod47d]

I was wonderin' what the "heat exchanger" inlet tube is on the atwood bowen The instructions say to hook a tube to it , but they don't refer to the function?!?

[Pick]

I just replaced my cold water heater this spring, with a new propane/electric unit. It does have a standard pilot, no electronics. After hearing a lot of complaints about appliances with "circuit boards", I decided on good old fashioned pilot light technology.

[Sasquatch]

I've had similar problems with spider webs, cocoons, dirt dobbers and wasp nests. I'm in Texas where we have all kinds of critters. We even have a small bee that will pack 1/8" or 1/4" tubing with flower petals. I put a screen over mine to keep most of the creepy crawly critters out. I also added a shroud over the top of my vents to deflect heat/soot away from the trailer wall. It runs the width of the vent door and is riveted to the wall above the vent. It sticks out about 1 1/2" and angles upward and out about 45 degrees and is made of 1/16 aluminum. I used a metal break to bend it and polished it to match my trailer. It looks factory.

[thenewkid64]

Pick,

When I replace my water heater I am planning on the same one you have. My past experience has sold me on the standing pilot. Unless it gets really cold at night the standing pilot will maintain the water temp in the tank. This way the roar of the main burner does not wake you up at night. I am also with you on the circuit board issue. No personal experience, but lots of related tales of failure at the most critcial times.