20 Most Recent Mr. Heater Natural Gas Garage Heater - 45,000 BTU Questions & Answers

Short circuited component/s at its internal circuit board.

Mr. Heater... | Answered on Mar 27, 2018

Check the flame sensor is clean . Also check out the pressure switch . Check out the snap disk high and low temp .

Mr. Heater... | Answered on Oct 10, 2017

I would check out the flame sensor it needs cleaning

Mr. Heater... | Answered on Oct 08, 2017

Is the circuit board giving you a blinking error code?
On a call for heat, the 24 volt thermostat sends a signal to the control module. The control module will indicate a call for heat with a light on the control either blinking or remain solid depending upon model. The inducer (exhaust) blower will purge all gasses from the furnace and pressurize a pressure switch. Once the pressure switch tells the module to continue, the electronic ignition will energize and send 120 volts to the igniter. The igniter will glow and you will be able to see it if viewed thru the small inspection port. Once the igniter gets hot enough, it sends a signal to the module opening up the gas valve (24 volts). Either a pilot will come on or the burner tube will ignite then spread the flame to all burners. Lastly a safety sensor will be looking for a certain temperature within a few seconds and the furnace will continue to operate and the room air blower will turn on in a minute or two.

What could go wrong? The unit will not run if there is no signal from the thermostat (bad thermostat or broken wire), the control module does not sense a signal from the thermostat (bad control), the inducer does not energize (bad motor), the pressure switch does not close (blocked vent piping, bad switch, plugged condensate hose), the igniter does not energize (bad control, bad igniter), the gas valve does not open or there is no gas (bad gas valve, broken wire, no gas), the pilot does not light (dirty pilot), the burner does not light (bad burner, plugged orifice, not enough combustion air), the flame does not spread to each burner (bad flame spreader, dirty flame spreader, more bad burners), the flame safety sensor does not detect flame (dirty or bad flame spreader, bad flame sensor, broken wire, bad control), or the room air blower does not energize (bad fan motor, bad control).

Mr. Heater... | Answered on Dec 03, 2016

If the fan does not run that causes the unit to over heat that in turn shuts every thing down.Check and see if the motor is not burnt out.

Mr. Heater... | Answered on Dec 16, 2015

The infrared heat/light sensor is either faulty or covered up (soot?)

Mr. Heater... | Answered on Sep 07, 2015

Take side cover off and you will see a little and your igniter should be in there

Mr. Heater... | Answered on Mar 28, 2015

sounds like its not getting gas fast enough to keep burning,that happen to me and the gas line was to long of a run for enough gas keep coming. so I up the pipe runs real good the flame keeps burning, so you know you can only go 25 ft in half inch pipe then u lose your flame

Mr. Heater... | Answered on Nov 20, 2014

Look for a flame sensor located in the flame of one of the burners. It will look like a small rod or probe and will have only 1 wire going to it from circuit board. Polish it with a scrub pad or stiff wire brush. Check the wire for a good connection as well as any ground wires off of the circuit board.

Mr. Heater... | Answered on Jul 03, 2014

The capacitor in that unit is for starting the motor that drives the blower fan. It has no impact on the ignition of the gas burner. On the control board, there is a light that should be flashing, can you tell us how many times it is flashing?

Mr. Heater... | Answered on Feb 19, 2014

I am only guessing since you have not given very much information. I would check to see if you have the power phased right. Some boards are polarity sensitive. Which means that the common should not have voltage to ground. Check and make sure L1 has 120 volts to ground and common. and that you have 0 volts from common to ground..

Mr. Heater... | Answered on Jan 31, 2014

Problem: Your furnace will not ignite the gas to produce heat for your home. When a furnace has a bad ignitor what I see most of the time is the following sequence of operation:

1. Thermostat calls for heat. 2. Draft inducer motor starts. 3. Pressure switch attached by a small plastic or rubber tube senses the negative pressure produced by the draft inducer and closes. 4. Draft inducer runs for 30 seconds to a minute before you hear a gas hissing sound. The ignitor did not glow, the flame sensor (a small metal probe about 1/8" in diameter, with a white porcelain base) does not sense the flame, so after 8 to 10 seconds the hissing sounds stops with no ignition of gas to heat your home. Your furnace shuts down and goes into a lock out condition until you turn your power switch back off and on again. Then the sequence starts all over again with no ignition of the gas. Solution:You probably need to purchase and install a new ignitor. I would suggest that you inspect your ignitor closely for cracks. Make sure you do not touch the ignitor with your bare hands. If you do not visually see a crack, then you could have a furnace control board problem or a limit, rollout switch problem. The furnace's control board might not be supplying the voltage to the ignitor.If your furnace lights and the gas stays on for 8 to 10 seconds, then shuts right back off, then you need to clean your flame sensor with light sand paper or steel wool. You might need a new flame sensor, but most of the time they can be cleaned an will work well after cleaning.

Mr. Heater... | Answered on Jan 27, 2014

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