Good article
I agree with what you've said.
My Monitor 422 was 6 or 7 years old (with no maintenance) and had the following problems:
- The flame sensor kept shorting on the burner ring, shutting down the heater.
- The flame was yellow and flashed frequently.
The unit was WAY overdue for basic burner service and I had been putting up with these problems for a couple of seasons. I knew it wasn't running efficiently and $3/gal kerosene provided the incentive I needed to service it. In online/email conversations with Monitor techs, I was told that I needed to replace the burner ring and burner cloth.
I ended up rebuilding it with a complete new burner pot and flame ring ($200 for the parts). It was a much easier job than I anticipated. Although it took me ~2 hours, the next time it will take considerably less, as I know exactly what's involved. I plan to rebuild the original burner pot by cleaning it and installing new burner cloth, so I'll only have to buy a new burner ring next time ($75), saving me $125. The reason I spent the extra money this time was that it was the middle of the heating season and I didn't have the time to clean the old burner pot and wait for the cement for the burner cloth to dry (~24 hours). Now, I can rebuild the old burner pot at my convenience and have it ready when I need it in 3 years or so (I vow to do maintenance as necessary, this time).
Here are a few tips for anyone considering this job.
- Directions for the job are included in the repair manual (~$30). I stumbled upon a copy that was posted online, but couldn't find it again. Searching may turn it up.
- If you're not sure how the heater is assembled, take digital pictures of the process so you can easily retrace your steps.
- Keep the screws with the parts they attach.
- The one special tool you'll need is a #2 Phillips screwdriver that's ~24" long. It's necessary to get to the left rear screw that holds the burner housing to the base (and it's handy for the right-rear screw). I used 1/4" drive screwdriver handle with a pair of 10", extensions on it to get the necessary length. I installed a 1/4" socket on the end, then inserted a Phillips screwdriver bit. It worked fine.
- Avoid inverting the burner housing until after you've removed the burner pot. Otherwise, loose debris will fall into the end of the housing where it can be difficult to remove (it gets caught in baffles in the housing). Lay the housing on it's side when removing the burner pot and it's four screws.
- The gasket at the bottom of the burner will need to be replaced. Monitor wants ~$20 for the part, but I found a similar 6 5/8" diameter gasket at a heating supplier for $3.49. I had to enlarge the inner diameter from 4 3/8" to 5 1/4" to match the ID of the burner housing, but that took all of 5 minutes. I used some of the trimmings to fill some unneeded holes in the gasket, but that probably wasn't necessary.
- I marked the holes for the burner housing screws on the gasket with a pencil, then punched them out with a leather punch, but you could probably just drive the screws right through the gasket material without punching the holes.
- The gasket between the burner pot and the burner housing did not need replacing on mine, but it may on others. I've been told that rope burner gasket material works best there.
After the rebuild, the heater fired right up and it's running like new. It was well worth the effort and I won't hesitate to do it again when necessary.
Anyone with reasonable mechanical aptitude can handle this job.
One warning: the new gasket material will give off a pretty serious odor the first time you start the heater, so be prepared to ventilate the room for the first half hour or so. After the material has been thoroughly heated once, you won't get any odors.
