Monitor 441 Heater

[mike45]

It looks like all it needed was a good cleaning. I vacumed out the heat chamber or whatever you want to call it. I took out the heater on the bottom of the chamber and vacumed every thing out. There wasnt a whole lot of loose stuff in there. Maybe I just got lucky. I love it when that happens. Now my wife thinks Im the best, plus i saved some money. HEH, HEH.

[veggigolf]

Hi, sorry to continue this thread but it seems this is the place for Monitor heater problems. I read in part of this thread that if the float is down, to adjust something in the left rear of the float chamber. What's going on with mine is when the chamber fills up with kero, the float magnetizes to something and stays up there. Then the pump drains the chamber and the float stays there. I can push the red button and get it to go down, but then when it comes back up it sticks every time. Anyone have a suggestion?

Thanks!

[veggigolf]

After looking at the manual download (see "The DEFINATIVE Montior thread")
I did not see anything about servicing the "constant level valve". It appears that the magnet is some sort of safety shut-off. Am I right in assuming the float should not be engaging the magnet every time it fills up?

I removed the magnet from the plastic case and the heater seems to be running fine, no overflow, plenty of fuel to the pot. But I'm scared that if something blocks the needle valve I may return home from work to a house full of kerosene!

Any advice is appreciated. I actually have a 422 but it is very similar to the 441. I did run this heater 2 years ago on 20% biodiesel and did end up with problems. Nothing like the major funkness problems others have reported after using 100% bio, I've just cleaned the fuel components occasionally and changed the filter.

[HayZee518]

the constant fuel level float is basically a float within a chamber like an old car carberator. the float pivots on a wire rod and on its extreme end is a springy like tang that contacts the needle valve. there is a extremely fine grub screw with a slot in it that you vary in or out to adjust the level of the float. too far in won't give you enough of fuel, too far out will overflow the chamber and lock out the system. if there is a surge in the chamber the float goes up and contacts the magnet which holds the valve closed against its seat. the old m41 heater used a mechanical toggle-over center lockout with a spring. USE ONLY K-1 OR DYED KERO - DO NOT USE BIODEISEL! Yeah its cheaper and easy to produce, but creates a lot of problems with monitors. I heard that bio is slower than mollasses when its flowing IF its not heated. It also gums up the solenoid pump and at $146 a whack I'll use kero Thank You. I can help you with most problems for an M41 or a 441 heater other than the computer board which I have no references to rebuilding. I have a pdf file service manual for the 41, 21, 441 and 422 heaters. I'm still looking for a manual for the 2200 and 2400. My supplier said he'd get me a service manual for the 2400. I'm still waiting!

[veggigolf]

Thanks Hayzee. Yeah, I found out about B20 kerosene (80% kerosene, 20% biodiesel) the hard way. Hopefully by now (2 years later) I'm at the end of those problems! Even at 20%, biodiesel seems to break down kerosene, making it cloud up, clog filters, gum up solenoid pumps, etc. There should probably be a sticky thread warning people not to use biodiesel with monitor heaters.

The heater ran just fine last night without the magnet, but when I get a chance to get dirty again, I'll put the magnet back in, adjust the needle valve in and see if it trips the magnet. I'd much rather have that peace of mind that it would shut down the system if need be!

One more question: the adjustment screw you are talking about, is that the needle valve itself? I can adjust the needle valve, but I haven't located any other adjustment screws.

[HayZee518]

The screw I'm talking about is most prominent on a m41 heater. The attachment picture shows it. My 441 expanded parts list shows the components but when I increase the size of it - I can't make it out too good. If you can't find an adjustment screw on the float then it isn't there - sorry. All the needle valves I've seen are free moving up and down with a triangular shaped rubber seal boot - inside the brass seat.

[MEWelding.com]

All of the connection points going to the fan are getting 120 v and the fan itself is getting hot but no operation, turns freely by hand.

Thank you.

[HayZee518]

then you need to replace the fan motor - it costs around $146 last time I bought one.

[MEWelding.com]

There are 4 wires that connect to the fan, 2 of which are not on a single plastic connector. Does it matter in which position these two wires go? Positive / negative?

[HayZee518]

the way you do the job -- is -- unplug the unit, take the front panel off. unfasten the through the wall inlet/exhaust tube and move the heater to where you can work on it. remove the flex line on the blower outside the heater unit. unfasten the rubber elbow inside the unit. unscrew all the screws that hold the fan in the unit. remove the screws that hold the impeller cover and pull off the impeller - this has a left hand thread. make a diagram of how the impeller goes on taking into account the spacers. unscrew the motor and put back together reverse order.
two wires go to the motor, the other two go to the damper solenoid.