Mr Heater Big Maxx Won’t Ignite [5 Easy Fixes]

It’s a sore sight to see that your Mr Heater Big Maxx won’t ignite the gas. It usually happens because of blockage leading up to the pressure sensor.

The pressure sensors get blocked due to a clogged vacuum hose, and blockage in the exhaust pipe.

This problem can also be caused by faulty flame sensors, malfunctioning inducer fans, and blown fuses. Keep reading this article to find out more about these problems and how you can solve them.

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Mr Heater Big Maxx Won’t Ignite [5 Easy Fixes]

Mr heater big Maxx ignition problems occur frequently after using it for a year or two. You need to look at the LED light of your circuit board to determine the problem.

If the light blinks thrice, the pressure switch is either stuck open or closed. That’s why the gas won’t ignite. Here are the most common solutions for this problem:

Note: You can also read the Duraflame infrared heater troubleshooting guide.

1. Clogged Vaccum Hose

The vacuum hose beside the inducer motor of the heater connects with the pressure switch. The metal cabinet and the vacuum itself can get clogged easily with time. That stops the heater from igniting the gas.


The first thing you need to do is to clean the metal cabinet the hose sits on. It’s a metal object, so you don’t have to worry about damaging any parts. Get something you can use to poke at the metal cabinet.

You can choose a wire twister to clean the cabinet. Stick it in the cabinet up to at least one and a half-inch inside the cabinet. If there’s any dirt in the cabinet, it’ll come out when you’ll pull the wire twister.

To fix the vacuum hose, blow air into it. If it’s working fine, you’ll hear a clicking sound which means that the pressure switching is turning on and off. If you hear the sound, your problem is fixed.

To check if this has worked or not, restart the heater. The green light should blink slowly now instead of blinking three times. The blinking will get faster as the thermostat will call for heat. Then, the gas will ignite.

2. Blockage In Exhaust Pipe

The pressure switch may be stuck if dirt has built up in the exhaust pipe. A quick way to check this would be to go toward the end of your exhaust pipe and inspect it. If you hear a strong draft, the exhaust is fine. Otherwise, it’s blocked.


You have to clean the exhaust pipe to remove the blockage. You can clean the exhaust pipe using a vacuum cleaner or you can take it apart, clean it, and put it back. If the heater ignites properly now, the exhaust pipe was the issue.

3. Faulty Flame Sensor

Carbon can build up in the flame sensor which will cause it to not function properly. The flame sensor needs to send the right data back to the control board, If it fails to do that, the heater won’t keep igniting the gas.

The symptom of a faulty flame sensor is that the burners will ignite but it’ll keep turning off automatically. It’s time for you to clean the flame sensor if this happens.


Mr Heater Big Maxx flame sensor cleaning is easy. You need to take it apart from your heater and wipe it using a sand cloth.

Sanding with the front side of the sensor can leave grooves in the sensor which will collect carbon.

Use the back of the sand cloth to clean the flame sensor. Take your time and put it back carefully without getting in the way of other parts. It’s best if you clean the flame sensor once a year so it’s always functional.

4. Malfunctioning Inducer Fan

The inducer fan has to be turned on first before igniting the gas. If the fan is not working properly, the heater won’t even try to ignite the gas.

The green light may flash steadily to signal it if you have a malfunctioning inducer fan.


The fan won’t run if the circuit board fails. So, the first thing you should do is make sure that the circuit board is okay. Try cleaning the fan first and see if it works. If it doesn’t work, you need to replace it.

5. Blown Fuses

If your Mr heater Big Maxx won’t start, blown fuses are a common culprit behind it. Fortunately, it’s very easy to fix and replace.


If the fuse is blown, replace it with a new one. It won’t cost you much and your heater will be up and running again.


What does Mr. Heater Big Maxx no LED light mean?

It means that the power is not on. Check if you have plugged the heater properly. The problem may also occur because of a faulty power outlet or a blown-out fuse.

Is Mr. Heater’s Big Maxx pressure switch open or closed bad?

The green LED light will blink three times at a slow pace to indicate that the pressure switch is open or closed. This is bad because the ignition won’t work until it’s fixed.

Why does Mr Heater’s Big Maxx ignition turn on but keep shutting off?

Faulty flame sensors are the most common reason if this happens. If the flame sensor doesn’t send the correct reading, the ignition will automatically turn off.

What causes a whistling noise when Mr. Heater is lit?

Mr. Heater can make a whistling noise if the air channels of the heater are blocked or air has gotten into the gas valve.

Is Mr. Heater’s Big Maxx’s green light flashing a normal thing?

Yes, it’s completely normal. The light will blink slowly when you turn it on and it’ll blink fast before the burner ignites the gas.


Now you know that Mr. Heater Big Maxx won’t ignite problem can be caused by many factors. If you hear that the fan of your heater running, the problem is likely to be with the pressure switch, exhaust pipe, or flame sensors.

If the fan doesn’t turn on, there may be a blown-out fuse, or the fan is clogged. Hopefully, this troubleshooting guide will help you figure out what’s wrong and how you can solve it. Drop a comment below if you have any questions.

About David

David is a man who loves doing research and finding out the best solution to any type of heating appliance issues like heaters and fireplaces. Whenever he finds the perfect solutions to any issues of heating appliances after doing in-depth research, he loves to share them with his readers. In fact, his aim is to help his readers to fix the issues with their heating appliances easily.More about us .

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