Original Bowen-Atwood Water Heater

This 10 gallon water heater was probably the toughest appliance to both return to operating condition, and test. I’m sure most people would have replaced it, but I like a good challenge & figured I would be happy if I could get at least one season out of it.

Although it was a bit of a task to make fittings to hook it up to city water, once the valve was turned on, the tank held pressure just fine. It was allowed to sit for a day or so with full water pressure just to make sure it had no pin hole leaks.

Interesting thermocouple on this era of water heater. Instead of being encased in cigar shaped enclosure the thermocouple was simply two cylindrical plates bonded together. Since the thermocouple & pilot light looked fairly nappy, I thought about replacing the assembly. But modern day parts would not work without more modifications than I wanted to do at that particular time, so I decided it could wait until the water heater proved it was up to the task.

Encouragingly, the pilot light lit without much effort. Turning the control knob over to ON, I could hear the hiss of gas, but could not see any flame at the main burner. Just before I turned the gas off, this huge fireball whooshed off the face of the unit, and a non-contained flame continued at the bottom. Kind of reminded me of the part in that atom bomb film where the shockwave from the bomb leaned trees over in its path.

No damage to anything, so I forged ahead & determined there was an obstruction in the main burner tube. But I could neither see nor remove the obstruction. Unfortunately, while removing the burner tube, the pilot light gas line twisted apart while being removed. Vendors think very highly of that particular piece of plumbing with fittings.

Surprise, surprise…the obstruction was a mud dauber nest.

Moving my 10 lb. Amerex ABC fire extinguisher a bit closer this time, I again fired up the works. This time, though, it worked like it was supposed to until the thermostat signaled “hot enough”. Most of the gas shut off, but there was still just enough coming out the main burner to keep a flame in the wrong place while in “pilot” mode. Disassembling the control unit in place, the main gas valve was found to have a small amount of contamination on its sealing surface. Cleaning this off allowed the water heater to function properly.

Testing the water heater consisted of letting it heat water, open valve until cold, then repeat. This, in addition to letting it sit there over a weekend maintaining hot water.

In retrospect, I goofed when reinstalling the water heater. Airstream technicians installed trim plates on the inside wall to beautify the hole. Since I had them, I reinstalled them. No big deal, but when the bathroom cabinet is installed, you can’t get to the rivets holding those plates in place. Not sure what I am going to do if I should ever have to replace this water heater!

Update: Four years later

The water heater appears to be ready for yet another camping season. I did have a problem with it last year when the pilot light started blowing out. It appeared that too much baffle-plate metal had rusted off of the pilot light/thermocouple assembly.

The solution was ThermoSteel:

Neat stuff. In the bottle, it looks a lot like watered-down Elmer’s glue with ground-up metal filings.

Following the directions, the rusted-out areas were coated with the goop and allowed to dry overnight. The next day, I lit the water heater and left it alone the rest of the day.

Success! The pilot stayed lit the entire day. We had several more trips that year, and had zero problems with the unit.

41 years on a water heater. Not bad.

Update: Eight years later:

Click here for a blog post I made in 2011.