Why Masterbuilt Propane Smoker Won’t Stay On [Reasons + Solutions]

Masterbuilt has to be one of the most reputable smokers out there. However, users do complain that their Masterbuilt propane smoker won’t stay on. From our experience, we can say that this issue is caused by one of the following reasons: 

Tripped excess flow valve, cold and windy weather, malfunctioning regulator, low-quality propane tank, blocked burners, lack of ventilation, and faulty thermocouple. Keep reading to find out how to get rid of this issue.

Why Masterbuilt Propane Smoker Won’t Stay On [Reasons + Solutions]

We’ll take an in-depth look at the reasons why your Masterbuilt smoker keeps shutting off. We’ll provide you with the simplest solution to help you overcome your struggle. Let’s get started!

Note: You can also read how to use MasterBuilt propane smoker like a pro.

1. Tripped Excess Flow Valve

The excess flow valve is a safety feature that determines whether the gas flow from the tank exceeds what is normally expected.

This is to prevent any gas leaks. In case the valve determines excessive gas flow, it will be tripped and the smoker will shut off.


To fix this issue and reset the tripped excess flow valve, follow these instructions.

  • Turn the burner control knobs to “OFF.”
  • Turn the knob on the gas cylinder valve to OFF.
  • To release the vapor lock, disconnect the regulator from the cylinder.
  • Hand-tighten the regulator to the cylinder until it sets into place.
  • Slowly open the gas cylinder valve and then continue by twisting one full turn to open the door even more.
  • Now it’s time to light the smoker.
  • Set the burners on high and light them with the igniter. 

2. Cold And Windy Weather

When you are trying to smoke at a low temperature when it is cold and windy outside, it can be extremely difficult to maintain the flame.

Even if the needle valve is in place, the flame could be blown out by the wind if it is exceedingly low. The colder the outside temperature the harder your smoker needs to work to reach a set temperature. 


Weather-insulating blankets protect your smoker from the elements. They are a great way to limit the damage done to your smoker by keeping it outdoors.

We recommend you invest in a high-quality insulating blanket and windbreakers. This should be enough.

In case the problem persists, you can try moving your smoker to a more sheltered place where the wind isn’t as strong or avoid smoking during bad weather altogether.

3. Low-Quality Propane

A lot of people have bad experiences with convenience store tank exchanges. You may get lower-quality propane that is high in impurities. This means that the propane doesn’t burn as long.


Always get propane from a reputable seller. Better safe than sorry.

4. Blocked Burners

In case you have a new smoker, this is an unlikely cause of this problem. However, within a few months of use, if you don’t clean up your burners, it could start accumulating debris. 

As smokers are stored away in garages or left outdoors, there is a chance that insects, spider webs, and mud daubers may block your burners.

Grease or other forms of debris can also be blocking your burners. Either way, this will block air and prevent combustion.


You can clean your burners with a simple burner brush. Try out other tools if needed. Once the gunk is cleaned out, your smoker should be restored to its normal state.

If the problem persists, inspect the connection between the regulator and the burner. There is a space in there where the structure may allow some air through. This space may have gotten blocked as well. Clean it if needed.

5. Lack Of Ventilation

To keep any fire ablaze you need oxygen. Also, carbon dioxide snuffs fires. So, for a properly lit flame, you need both air inflow and the outflow of exhaust.

You can control your gas flame by manipulating these two things. Poor ventilation can make your smoker shut off.


In case your Masterbuilt propane smoker keeps shutting off, you need to open up the air dampers to let the oxygen in.

This will put some zeal back into the fire. You need to open up the exhaust vents to let the excess smoke and steam get out.  

6. Faulty Thermocouple

When your Masterbuilt propane smoker burner won’t stay lit after releasing the temperature control knob during starting it up, the problem is caused by a faulty thermocouple or releasing the knob too quickly.


First, check that your Masterbuilt smoker thermocouple is in the position it is supposed to be in. You are supposed to hold down the temperature knob for 10 seconds which is long enough to heat up the thermocouple.

So, test your thermocouple by holding down the temperature knob for a slow count of 10 seconds. If the flame still switches off, you have a bad thermocouple at hand. Call in a technician to have it replaced. 


How do you keep a propane smoker at 225?

Set the vents entirely open when you start your smoker. Doing that will let your smoker reach the desired temperature faster. Set the vents halfway closed to maintain the temperature.

How often do you add wood chips to a propane smoker?

Adding new wood chips every 30-40 minutes is a good idea. Two to three handfuls of wood chips will smoke for about an hour, so keep adding chips to keep the smoke rolling and get the finest flavor.

Can I use wood chunks in my Masterbuilt propane smoker?

Yes, wood chunks can be used in a gas smoker if the smoker is intended to accept this size of wood. Many gas smokers have a shallow tray to keep their smoking wood, which they usually recommend wood chips.

How to regulate temp on Masterbuilt propane smoker?

You can regulate the temperature by adjusting the air dampers and the exhaust.

What is the best oil to season a smoker with?

Canola or peanut oil is best to use to season a smoker. This is because they have a high smoking point which ensures they won’t burn. Sunflower oil, vegetable oil, or avocado oil are good enough as well. 


All these causes are easy to fix. With just a bit of electrical knowledge, you can fix them yourself.

Hopefully, you now know what to do when your Masterbuilt smoker won’t stay on. Cheers!

About William

William is the founder of Fireplacehubs.com. He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

2 thoughts on “Why Masterbuilt Propane Smoker Won’t Stay On [Reasons + Solutions]”

  1. This is the first time to use the new smoker after going through the initial high temperature initial oil cleaning. I have some pork chops, sausages and veggies. Smoker gets almost to the 225 degree temperature and the burner shuts off and remains off until temperature is well below set point, about 50 degrees. Restarting with a higher set temperature does the same thing. Burner sounds a little noisy.

    • Hi Gary

      Propane smoker shuts off due to one or more reasons like tripped excess flow valve, cold and windy weather, a malfunctioning regulator, low-quality propane tank, blocked burners, lack of ventilation, and faulty thermocouple.

      Well, as your smoker is a new one, check whether there is any lack of ventilation or not. You can open up the air dampers to let the oxygen in. This will put some zeal back into the fire. You need to open up the exhaust vents to let the excess smoke and steam get out.

      If ventilation is ok & you are facing the same issue, then it would be wise to contact the Masterbuilt customer support center as you must cover the warranty period.

      Wish you all the best.


Leave a Comment