Monitor 30 thermistor?

[woodauger]

My setting is high by about 15 degrees - heats the room to 68 when set at 55. Does anyone know if adding a resistor in series will solve this? Also looking for a schematic as one of the burner level relays is failing. Thanks Gary

[HayZee518]

not sure what you mean "burner level relay?" if your system uses the economy plus option, the heater will overshoot the setpoint by 12 degrees. normal without the economy feature it will overshoot by only 2-4 degrees.
I don't know what a normal resistance at what degree setting is. I'll find out.

[woodauger]

Thanks, HayZee

not sure what you mean "burner level relay?" if your system uses the economy plus option, the heater will overshoot the setpoint by 12 degrees. normal without the economy feature it will overshoot by only 2-4 degrees.
I don't know what a normal resistance at what degree setting is. I'll find out.

I don't know the 'economy plus' option - was this on the older Monitor's? The heater does a great job at maintaining 68.5 - but it's set at 55. I'd like to be able to leave the house at 45 if I'm gone a couple days. I may be mistaking a buzzing sound when the burner level drops from 'high' to 'medium' for a bad relay. I didn't know what else might control the burner level

[hawkins111]

There is a procedure in the manual to calibrate the room sensor. It has been 15 years since I worked on a M 30. I think there is someone on this forum that has a manual. I will try to find mine and send the procedure to you. Tom

[woodauger]

Thank you, Tom

There is a procedure in the manual to calibrate the room sensor. It has been 15 years since I worked on a M 30. I think there is someone on this forum that has a manual. I will try to find mine and send the procedure to you. Tom

It's made a huge difference in my home's comfort, enabling me to leave the whole-house dinosaur turned off. I have a 422 backup, but the 30 is running so well I hesitate to fix what isn't broken. Gary

[hawkins111]

3-18 MONITOR TEMPERATURE CALIBRATION Amount of heat output by Monitor 30 system is regulated by a temperature sensitive, Heat Sensor. Basically, the Heat Sensor operates in the following manner: If temperature of the room drops below a predetermined point, the sensor"senses" the temp*erature change and signals the Monitor to produce more heat; and conversely, as temperature of the room rises to the "comfort" level, the sensor signals the Monitor to reduce its heat output. But because the efficiency and economy of Monitor operation is dependent upon how well the Heat Sensor "senses" temperature changes, a tempera*ture calibration procedure is performed foroptimum performance. Following heater installation (including wall-mounting of the Heat Sensor), proceed as follows:

STEP 1: Check Temperature Calibration Position thermometer next to the wall-mounted or fan guard mounted heat sensor. Press ON/OFF push-button switch. Press MANUAL push-button switch. Set TEMPERATURE Selector control to 75°F. Observe indicator lights on heater, and tempera*ture indicated on thermometer. Confirm that HIGH indicator lights after heater reaches oper*ating temperature. Verify that HIGH indicator light goes off when temperature of the room (as indicated on the thermometer) nears 70cF.

NOTE: If HIGH indicator light does extinguish as noted in Step 1 F, no calibration is needed.

STEP 2: Calibrate Heater

WARNING:

ELECTRICAL INTERIOR CONTROLS ARE AD*JUSTED WHILE POWER IS APPLIED TO THE INSTRUMENT.

Press ON/OFF push-button switch to position OFF. Unplug heater from wall socket. Remove Front Cover. Remove the Control Panel mounting bracket (to the left of the Control Panel) by unscrewing the two (2) Phillips head screws. Removal of the mounting bracket allows access (through a cut out in the Control Panel) to the manually variable resistor used to calibrate the heater. Plug power cord into wall outlet and press ON/ OFF push-button switch to position ON. With a very small insulated screwdriver, or phenolic probe, adjust the TEMPERATURE CALIBRATION control by gently pushing it clockwise to lower heat output and counter clockwise to raise heat output. The control is identified by the inscription "VR2" on the PCB. Check temperature calibration as specified in Steps 1 E and 1 F of this procedure. If heater is properly calibrated, proceed to Step 3. If not properly calibrated, repeat Step 2F as many times as necessary until temperature is properly calibrated. After calibration is complete, replace Control Panel mounting brackets. Replace the front cover. Turn the heater on. Reprogram the current time.

[Bryand]

My setting is high by about 15 degrees - heats the room to 68 when set at 55. Does anyone know if adding a resistor in series will solve this? Also looking for a schematic as one of the burner level relays is failing. Thanks Gary

There is no economy plus on the Monitor 30. You can make the adjustments on the control panel or move your thermostat sensor higher up on the wall you should have plenty of cord to move it around.

[woodauger]

Thanks again to Tom. The calibration instructions brought the thermostat right into line. Now if I can figure out how to get the three feet of predicted snow off of my roof....