Heatilator Gas Fireplace Low Flame [Why + How To Fix]

The main reasons behind the Heatilator gas fireplace low flame are low gas pressure, burner issues, incorrect air shutter position, bad logs placement, and faulty valve motor.

heatilator gas fireplace low flame

More often than not you can solve this problem by adjusting the gas pressure and cleaning the burner. However, that doesn’t mean that you should ignore the other reasons as they can cause the issue as well.

Keep on reading this guide to know all about them in detail and learn how you can fix the flame height on your Heatilator gas fireplace. Let’s dive in!

Heatilator Gas Fireplace Low Flame [5 Easy Fixes]

If you’re using a Heatilator fireplace, there’s a control knob that allows you to switch the flame height from low to high and vice versa. These two settings are most likely marked “Hi” and “Lo” on the control knob.

flame adjustment control knob

It’s frustrating when the fireplace doesn’t change the flame height when you turn up the settings and still produces a low flame. Here are the most common reasons behind Heatilator fireplace low flame:

Note: You can also read our guide on heatilator gas fireplace manual.

1. Low Gas Pressure

The gas pressure must be the right amount for your fireplace to stay lit and produce the required flame. When there’s a lack of gas pressure, it can create many problems.

One of those problems is that you’ll have a low flame even when you change the settings on the knob from “Lo” to “Hi”.

measuring the gas pressure

There are two types of pressure you need to be aware of. The incoming and the outgoing pressure. The outgoing pressure is also called the manifold pressure.

You can call in someone from your gas provider to check the pressure at both taps or purchase a device called a manometer to check it yourself.

standing pilot ignition wiring diagram

Test both these taps while the burner is running. The inlet gas pressure usually ranges from 5″WC to 7″WC for natural gas and the outlet pressure usually should be less than 3.5″WC. If the pressure readings are lower than that in any of the cases, there’s not enough gas pressure.

If you have multiple gas appliances in your home like a gas furnace or a stove, it can also decrease the flow of gas to the fireplace when you’re using multiple devices at once and cause this issue.


If you find that you have low manifold pressure when testing it out, the first thing you can do is locate the manifold pressure adjustment screw and increase the gas pressure to the manifold.

Next, make sure that you’re using the right type of gas required by your Heatilator fireplace model.

Also, check that you have sufficient gas in the cylinder and make sure the supply line is working properly. If you have a leaking supply line, here’s how you can replace it:

  • Shut off the gas supply by turning the knob.
  • Turn down the gas valve of the fireplace.
  • Pull out the old pipe. If it’s secured with a lock, you’ll have to remove the lock and take the pipe out. Repeat these steps for both ends.
  • Attach the new pipe to both the fireplace and the gas cylinder.
  • Use metal locking strips to secure them in place and prevent any gas leakage.

If you did all that and your Heatilator gas fireplace’s small flame problem isn’t solved, it’s time to call a technician. The gas valve may have to be replaced in this case.

heatilator gas valve

The gas pressure may also need to be adjusted as changing to the wrong settings will lead to unsafe conditions.

2. Burner Issues

Another common reason behind low flame on Heatilator gas fireplace is having issues with the burner. The burner ports can become clogged after a period of long-term use and can keep the flame from burning properly. The burner itself can also become cracked and start to malfunction.

heatilator burner issues

The burner orifice can also get covered with spider webs or other dirt and debris. When you’re checking the burner ports, pull out the burner orifice and inspect it as well.


If the Heatilator gas fireplace flame goes out and it’s caused by a clogged burner or burner orifice, you can solve it by cleaning them. You’ll have to remove the glass front and the logs of the fireplace to get access to it.

Once you get to the burner ports, you can clean them by blowing compressed air through them and vacuuming all the dirt out. For the burner itself, you can rub it with a fine-grit sandpaper.

clean the burner with sandpaper

Also, push a swab of Q-tip into the tube behind the orifice & move it around. Obstruction in that area can also block the supply of gas. Make sure you clean it to solve this problem.

After you’ve done a thorough job of cleaning all of them, it’s time to light your fireplace again and see if you can adjust the flame height now. If the burner is damaged or cracked, you’ll have to replace it with a new one.

3. Incorrect Air Shutter Position

The degree to which the air shutter is open dictates how much air will be mixed with the gas at the burner orifice.

heatilator air shutter

If the air shutter is open too far, that will increase the quantity of air in the air-gas mixture. The result will be that you’ll get a smaller Heatilator low flame and you won’t be able to get it higher.


Adjusting the air shutter and closing it down a little bit should solve this issue. You won’t be able to access it from the controls area in most cases and you’d most likely have to displace the logs and the burner to access it. Once you adjust it, the flame level should go back to normal.

Keep in mind that if you close off the shutter too much, you’ll get a taller orange slow flame. You don’t want that and it’s a good idea to settle somewhere in the middle where you have a mostly blue flame with a little bit of yellow in it at a decent height.

4. Bad Logs Placement

Have you recently changed the position of the logs in your fireplace just before this low flame problem occurred?

bad logs placement

If you did, it could very well be the reason why you’re getting a small flame as the placement of logs can have a major impact on the flame height.


Placing the logs in the original position will solve this issue if you created them by moving them around. It’s always a good idea to take a picture of the position of your logs before you move them so that you can put them back correctly later on. 

But we’re guessing that you most likely didn’t get a picture. In that case, you can follow these steps as a good starting point to reposition the logs in your fireplace and hopefully, get a better flame height from it.

  • The largest logs should be placed at the bottom as they’re the foundation of the fire.
  • Leave a gap of at least 2 cm or 5 inches between the logs so that there’s good airflow between them and the flames can reach a good height.
  • Reposition the logs if any of them are blocking the gas flow.
  • Place the smaller logs on top of the foundation logs. Put them in random positions and don’t worry too much about being tidy here as you’d want to fire to look natural.

5. Faulty Valve Motor

If the Heatilator fireplace low blue flame issue isn’t caused by the reasons mentioned above, there’s a high chance that you have a bad valve motor. Thankfully, testing it out is easy and you can do it on your own.

It’s the small motor that’s responsible for adjusting the flame height when you change the flame height settings. Some of the models have mechanically adjustable flame level control which has no motor.

But if you have a 3-stage height adjustment, your model most likely has a valve motor. If you’re having trouble locating it, look for the wires that are leading from the control center to a small black circle in front of the valve system.

Take the motor out by removing the 2 Phillips head screws that hold it in place. Now, you’ll have to notice its movements to know whether it’s functioning properly or not. It should do about 6-7 revolutions when you start the fireplace.

It’ll also respond and switch to different positions when you adjust the flame height. The motor will also try to close the valve when you turn off the fireplace. If you don’t see these things happening, you can conclude that you have a bad valve motor.


If the diagnosis shows that you have a faulty valve motor, you’ll have to replace it so that you can adjust the flame height without any issues. It wouldn’t cost you more than $30 – $50 if you do the replacement job yourself.

How To Maintain Good Flame Height On Gas Fireplace

How do you fix a low flame on a gas fireplace? Now, you know it as you’ve learned about the major reasons behind it.

But by doing periodic maintenance of them, you can stay on top of things and make sure that you have a good flame height at all times. Here’s how you can go about it:

Step 1- Get Access To The Burner

  • Before cleaning the gas fireplace, it’s important to turn off the gas valve and shut off the gas supply. Rotate the gas valve perpendicular to the pipe to do it.
  • Take a picture of the logs you use in the fireplace so that you can place them back in the correct order after removing them.
  • Remove the gas logs to access the important fireplace components including the burner.

Step 2- Clean The Burner

  • Get the sand and dirt out of the burner with a small broom and a brush pan.
  • Take a good look at the burner orifices and clean them if needed. They’ll most likely have cobwebs, dust, or animal hair. Blow compressed air into the holes to get them out and clear any debris that can block the flame.
  • Inspect for blockages in the burner again as it needs to be free and clean for a proper flame. Push a thin wire through the holes to get any further dirt out of the burner and blow compressed air through them again.

Step 3- Straighten The Gas Line

  • Kinks in the gas line can also lead to a reduced flame height. So, inspect the gas line thoroughly and straighten it out if needed.
  • Place the fireplace logs back in by referring to the picture and turn on the gas valve.
  • Enjoy the nice and cozy heat from your fireplace.


What to do if the gas fireplace flame is too high?

The flame of the gas fireplace should be close to 3.5 inches. If it’s more than that, you may have too much gas pressure and it’ll need to be adjusted. If you don’t know how to adjust the flame on the gas fireplace. Read our guide on gas fireplace flame adjustment.

How to light a Heatilator gas fireplace?

Turn on the pilot light first by firing the igniter a few times while pressing down on the pilot control knob. Once it’s lit, move the knob to the “On” position and turn on the fireplace by pressing the switch or using the remote.

What should the gas fireplace flame look like?

While the pilot light should be mostly blue, the fireplace flame can be orange or yellowish in color. If the flame is too blue, it means that the fireplace is burning the fuel without any wastage and producing maximum heat.

How often should gas fireplaces be inspected?

Gas fireplaces require so little maintenance that it’s easy to forget that even they need some upkeep once in a while. Do an annual inspection of the fireplace during the summer months when it’s not in use.

How do adjust the flame on the Heatilator fireplace?

Depending on the model, you can either do it by turning the knob on the control area or by pressing the up and down arrow buttons on the remote.


It’s comforting to relax by your fireplace and watch the flames dance around. But this wonderful experience can get ruined when you notice a Heatilator gas fireplace low flame issue and notice that you can’t adjust it anymore by using the knob or the remote.

Hopefully, you’re no longer worried about this issue and this guide has helped you to diagnose and fix the main reason behind it.

Do annual maintenance of your fireplace to prevent these things from happening. Leave a comment below if you have any questions about this topic.

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.

Leave a Comment