Efficiency too high for temperature?

[woodauger]

Hi. I'm back begging again. Ran the Monitor 30 all winter in Tug Hill NY region. I left it at 53F Maintenance temperature as I'm still moving in. I spent a few days there in Feb, the outdoor temp dropped to -20F, no problem with heater (which switched up one heat level). I couldn't get back up until three days ago. House stank of kerosene. The heater had quit, tray filled with K1 - but not overflowed. Lifter pump was running and I turned it off. The combustion fan was still running and the indicators lit to "medium" run. Combustion chamber filled to the bottom of the plate with kero-soaked soot, and an inch of liquid kerosene at the bottom of the chamber. I'm wondering if the air intake is taking too much heat for the the low set temperature I left it at. The exhaust was also plugged up with soot. Is it possible the heater would run okay at 65, or warmer, on a regular living basis?
Thanks in advance - sorry if it's long winded. Gary

[HayZee518]

I would look towards the combustion fan not running at the proper speed. all that soot is because of insufficient combustion which the blower provides. check also the float in the pump chamber. it could have locked open which is a no-no.
check the air flow permissive pressure switch. if this thing didn't close then nothing heat related should have worked.
what you'll have to do now is clean out the whole combustion pot and replace the burn mat.

[woodauger]

clogged Monitor 30

I would look towards the combustion fan not running at the proper speed. all that soot is because of insufficient combustion which the blower provides. check also the float in the pump chamber. it could have locked open which is a no-no.
check the air flow permissive pressure switch. if this thing didn't close then nothing heat related should have worked.
what you'll have to do now is clean out the whole combustion pot and replace the burn mat.

Thanks HayZee - The heater is a real mess - and it did a fine job until the failure. I got a heads-up from National Grid (my power provider), a couple weeks ago. They were cutting off power to the NY house for 30 minutes. It seems pretty insignificant, as my online bills were always in line with the preceding month, but I still wonder about the effect of the interruption. Is there a method to clean the interior heat exchanger? I have a 422 to swap out with it, and am tempted to scrap it. I didn't know it has a burner mat

[HayZee518]

I'm not sure about a burner mat. I'll have to check my notes. To clean the heat exchanger you'll need to disconnect it from the combustion pot and the exhaust outlet on the unit's back going to the exhaust tube going outside. vacuum out what you can scrape out from both ends, then put some coarse dry sand inside it and flop it around all over the place to dislodge soot inside the bends. vacuum it out again. gently blow through the rubber hose on the permissive air switch to see if the microswitch closes. check some of these past posts for the resistance of the pot igniter. the overloads should be ok, all closed. take the sump apart and clean it out.
If tughill wasn't so far, I'd take a ride there to help you, I'm north of you on route 458.

[TechEditor]

There were some days in the Alex Bay - Watertown area where the exhausts would ice up. Happened to my Laser 73 and at least a half dozen others that I know of. Combination of extreme cold and the wind and snow just right.

[hawkins111]

To answer your question about the intake air cooling the exhaust too much, for the most part the answer is no. The air might cool the exhaust too much only if you have a very long extension that is running through an un heated space. Send us pictures of your exhaust.
You have several other situations going on here. One, the lifter pump was running. That only happens when the lifter sump is out of fuel. Two, the combustion fan was running and the Med Light was on but no combustion. This is not the way the stove works. With no combustion the burner light should be out and the fan should only run for a short time. Stove flooded. This can happen for several reasons. A sooted burner, heat exchanger and exhaust that will not allow the stove to burn the fuel completely. With incomplete combustion the fuel is not being burned fast enough and flow fills the burner to the level of the sump. Normally the sump would trip the float shut off and the stove would eventually shut off due to no fuel. Something else is going on to allow the fuel level to get above the air holes in the burner. A very sooted burner means a complete overhaul of your system. Burner, heat exchanger and flue pipe will need to be cleaned before you can proceed with the rest of your overhaul. It is my opinion you should scrap this Monitor 30 heater. They have not made parts for this unit for over 20 years, it has sub standard safety features compared to today's units, which makes it obsolete. All in all, get a modern day vented heater and save yourself a lot of trouble.

[akaothermick]

The monitor 30 is old, but that being said they are relatively brainless to repair and I have found parts still readily available for my Kerosun Monitor 30 unit, they lack safety features present in new units but so do older cars but they still get you from point a to point b, so if its heat you want it is capable of that, but yours needs a total clean out and refurbish, but if you are not up to it, sell it, a good technically inclined individual can put that unit back in service, the lack of safety stuff just means less you got to fix, lots of old 40 year old furnaces still putting out heat in peoples basements, with a thermocouple as the only safety feature. The HVAC guy hates to see them, no money to make on servicing them, he would rather sell you and nice new hi efficiency unit that needs service every season,

[woodauger]

I appreciate the reply, Tom. It ran so well all winter until the last week - but I took your advice and added and replaced it with a second 422 . I tried to download a pdf service manual online, but the printing is unreadable. My circulation fan runs on low when the heater is plugged in, even when unused. I assumed a stuck relay or bad capacitor, but lack a wiring diagram. Thanks, Gary

[hawkins111]

Gary, Are you talking about the M422 fan running all the time? If so you have the fan and over heat wires in the wrong place. I do not have a M30 manual in PDF. It may take a few days for me to answer as I'm off on a log raft trip for the next 4 days. Tom

[woodauger]

Gary, Are you talking about the M422 fan running all the time? If so you have the fan and over heat wires in the wrong place. I do not have a M30 manual in PDF. It may take a few days for me to answer as I'm off on a log raft trip for the next 4 days. Tom

I hope the weather favors your trip. Yes, the M422 fan. It ran fine as a temporary workshop furnace last year. Still runs great, but the fan is always on low after the unit cools. The fan starts when I plug the unit in, without turning it on. I mothballed the M30 until I'm established enough to make a decision

[hawkins111]

The blue wires go to the two overheat switches and the air safety switch. The red wires go to the fan thermostat.


We are looking at a good week end so it should be a dry trip.

Tom