Things that go KA-WHUMP!!!

[Mike L123]

Hi All!

This is with regard to our hot water heater. We have been full timing for 14 months now in the Cougar and things have been going really well in general with the RV. We had to replace the solenoids on the HW heater control valve about six weeks ago. About a week ago we started having to reboot the heater three or four times over a 24 hour period. I thought that this was because of the high winds we have been experiencing of late. However, we have noted a very loud noise, much as described in the title, over the last three days. Today with the windows in the slide out open we could really hear how loud this was becoming.

I took the cover off of the heater today and noted quite a bit of ash, soot and debris on the bottom of the box that looked like the result of backfiring and was never seen there before. I took the blow-back cover off and peeked inside the combustion chamber and everything looked to be pretty clean. We are currently boon docking and will be until October so we rely on propane full time for our water heating. As far as I can see there is no air adjustment on this Atwood unit so is there any way to choke the air supply a bit? Any other thoughts on this would be appreciated!

Thanks and Cheers!

Mike and Carol

[Halibutman214]

Needless to say it sounds like there is a pretty good buildup of gas before ignition. I don't know the fix but if it were me I would not continue using it. Some ka-whump is normal but from the way your describing it this is not normal and if it's getting worse could ka-whump you out. Good luck

[SAABDOCTOR]

I would first check themain jet in the gas line to see if anyone has moved in and clogged it a bit this will cause a poor spray and rough ignition. after that i would find an expert before you accedently depart the planet earth for a short trip to the stratosphere good luck

[campingcpl]

We had the same problem durring a camping trip where the winds were a little on the high side. What I found was happening in our case was that when the heater would try to fire the wind kept blowing out the flame and then when it would relight there would be a build up of gas and the spark would ignite the extra gas causing it to blow back out of the combustion area. I had a first hand view of this happening when I went out to check it out. The only way to try and prevent it is to try and block the wind from hitting the vent area with out block the vent area. I backed the truck along side the trailer and that seemed to help block a lot of the wind.

[Mike L123]

OK friends. Is there any chance that someone out there with a 6 gallon Suburban w/h could take a look and tell me if there is any kind of an adjustable choke on the burner/orifice tube? Mine does not have any method of restricting or adjusting the airflow. I have checked the schematics and the image does not really clarify the question for me. I checked a couple of other RV's in the hood and they all have an adjustment for the air intake to the tube. I need to know if mine is somehow MIA. I have cleaned and inspected every inch of the combustion chamber and so on and I have no obvious issues.

As always, thanks and Cheers!

Mike and Carol

[Festus2]

Mike -
I have a 6gal Suburban W/H and there is nothing that is adjustable on the tube. I think on older models (very old) there used to be a sliding sleeve that you could move back and forth over the hole to increase or decrease the amount of airflow. This tube has an opening to the right of the gas valve, but there there is no adjustable part anywhere on that tube.

[Cool Canuck]

Originally Posted by Mike L123

Hi All!

This is with regard to our hot water heater. We have been full timing for 14 months now in the Cougar and things have been going really well in general with the RV. We had to replace the solenoids on the HW heater control valve about six weeks ago. About a week ago we started having to reboot the heater three or four times over a 24 hour period. I thought that this was because of the high winds we have been experiencing of late. However, we have noted a very loud noise, much as described in the title, over the last three days. Today with the windows in the slide out open we could really hear how loud this was becoming.

I took the cover off of the heater today and noted quite a bit of ash, soot and debris on the bottom of the box that looked like the result of backfiring and was never seen there before. I took the blow-back cover off and peeked inside the combustion chamber and everything looked to be pretty clean. We are currently boon docking and will be until October so we rely on propane full time for our water heating. As far as I can see there is no air adjustment on this Atwood unit so is there any way to choke the air supply a bit? Any other thoughts on this would be appreciated!

Thanks and Cheers!

Mike and Carol

Something is wrong with the gas valve.

[Mike L123]

Festus2 - Thank you for reassuring me about that. At least I know that I'm not missing any parts or pieces.

Mr. Canuk, I agree that there is likely an issue with the gas valve. I am trying to track down a new one through a local friend of mine who used to do RV repairs. Hopefully this will fix the problem as we are getting tired of no hot water in the mornings. Remember that if momma ain't happy ani't nobody happy!

Cheers Friends!

Mike and Carol