Patio Heater Repair & Troubleshooting: The Ultimate Guide

Heating inside your house is easy but heating your patio or garden space is a bit more challenging. The cold weather and exposure to the elements can mean your patio is basically unusable in the winter months. That’s where patio heaters come in handy.

Patio heaters are designed to overcome these challenges and provide a reliable heat source all year round, which is why it can be so frustrating if they stop working. This guide looks at lighting up a patio heater and how to identify and solve various problems you might face.

Signs of a Malfunctioning Patio Heater

Before you can go about fixing your patio heater, you need to understand if there’s an issue. Some problems can be easy to spot, whereas others are a bit more concealed. Here are the telltale signs that your patio heater is malfunctioning:

Patio Heater Won’t Start

This is a pretty obvious one, but if your patio heater won’t start at all, there’s probably a malfunction. This can be caused by a damaged igniter, or if there’s an issue with the supply of fuel. We’ll come to the solution later in this article.

Flame Is Much Smaller Than Usual

Your patio heater relies on a flame for the heat source. If you notice the flame is smaller than usual or the heat coming from the unit has reduced, then there is probably a malfunction relating to the gas pressure that you’ll need to deal with.

Heater Stops Working After A Few Minutes

Many people experience their patio heater lighting and then stopping after a few minutes. There’s a couple of different reasons for this, but it’s a clear sign that your patio heater is broken and needs attention.

Reduced Heat Output

You should keep a close eye on how much heat is coming from your heater. If you notice it’s not working as well as it was, then you’ll need to repair it as soon as possible because it can lead to more problems down the road.

9 Most Common Patio Heaters Problems & Solutions

Every outdoor heater is different, and they can have very different problems, but you’d be surprised how many times it’s similar issues. Here are 9 of the most common problems and how to solve them:

1. Pilot Light Problems

Thermal Coupling for Gas Heater

Your pilot light is used so you can tell if the gas is flowing into your patio heater. You should typically be able to see your pilot light from the front of your heater, and if you can’t, then there is probably an issue.

You’ll need to see if there are any clogs in the line preventing gas from flowing and examine your internal components. Remove the screen covering your pilot light, and then run some compressed air through your pipes to remove any blockages.

Once this is done, your pilot light should start working, and your heater will be able to ignite.

2. Thermocouple Problems

Your thermocouple is designed as a safety component that controls the flow of gas. If your pilot light goes out, the thermocouple will stop the gas supply, so it doesn’t just flow out.

If your thermocouple has an issue, then you may smell gas coming from the unit when the burner isn’t lit or that your propane is going down faster than it should. It may also be shutting off the heater a few minutes after use.

The easiest thing to do is lift off the front panel and replace the thermocouple using a wrench. This is simple enough to do from home.

3. Carbon And Corrosion Problems

Over time, carbon can build up around the patio heater, so it starts to block the main orifice. You can unblock this easily using a toothpick or other thin piece of wood or metal to remove this carbon. You can also use sandpaper or a rough surface to file this down until the patio heater starts working correctly.

4. Loose Connections & Fittings

Often the issue is just as simple as a loose connection. The first thing you’ll need to do is find the connection, and you’ll have to see where the issue is. If it’s related to the flame, it may well be the ignition, but if it’s the heat level, it could be your gas line.

Check each internal component and then use a wrench to tighten the connection until the patio heater starts working correctly.

5. Flame Is Too Low

Flame in the Patio Heater is too Low

If the flame is too low, it likely means that there isn’t enough gas reaching the burner. If your gas tank is less than ¼ full, this might cause the issue, so you’ll need to replace it.

Alternatively, it could be an issue with the supply line, so if your gas tank is full, then you should purge the air from your lines by turning the gas flow fully on and pressing the control knob for 2-3 minutes.

There could also be a kink in the line, so look to straighten it out, and if this doesn’t work, you can try replacing the pipe.

Hopefully, one of these solutions will increase the gas pressure going to the heater and solve the problem.

6. Low Heat Levels

If your heat level is starting to dip, you may have a gas leak in the pipe, preventing all the fuel from getting to your burner. These leaks should always be handled cautiously to prevent any risks to your health or anyone else in there.

You should start by ensuring there are no kinks in the line and then using a specialized leak spray to find the leaks. Once you find them, you can replace that section of pipe using a wrench, but make sure the replacement pipe is the appropriate size so that the gas can flow correctly again.

7. Infestation of Bugs and Critters

This isn’t always what you think of when your patio heater stops working, but it’s a common problem. Insects and bugs can get in and around your patio heater as they look for warmth or become attracted to the heat.

Small insects and animals can cause havoc to your patio heater, and there is nothing worse than having these cooking in your device while you use it. You should do a quick check and sweep every time you use the heater and clean it regularly to resolve this.

8. Faulty Electric Heater

An electric patio heater may stop working because of a faulty heater within it. This is usually caused by faulty wiring or damaged wires caused by overuse. The bad news is that this wiring is complicated to fix yourself, and you’ll probably need to consult a professional to have this one resolved.

If the wiring problem is bad enough, then you may need to replace the whole unit.

9. Sizing Problems

Unlike the other problems on the list, this one probably shouldn’t take you by surprise because it’s likely caused by the user. When you’re replacing parts within your patio heater, you need to ensure you have the right size for each component.

If something is too large, then it won’t fit, or the heater won’t work. The only real solution is to go back to the store and get the right size so you can repair it correctly.

How to Bypass Thermocouple on a Patio Heater

How to Bypass Thermocouple on a Patio Heater
A thermocouple is a piece of metal tubing that controls the flow of gas into your heater. It’s designed as a safety component that only allows gas to go through if the pilot light is on and it’s going to be used.

Thus, it prevents gas from flowing into your heater unnecessarily and causing potential harm to you and your family. The thermocouple is also attached to your tilt switch so that if your heater tips over, the gas will stop flowing.

Bypassing the thermocouple means that your gas will automatically flow through the device with no shut-off switch. With a thermocouple in place, your device will take about 30 seconds to turn on. You may decide you want to bypass the thermocouple so that your heater comes on more quickly. Here’s a quick guide on how to bypass it:

  1. Open The Front Assembly Cover
    Start by opening up the assembly cover to allow you access to the inner mechanism.
  2. Locate The Tilt Switch
    Follow the thermocouple wire down to the tilt switch. Take off the wires connected to the switch and connect them together to create a safe circuit.
  3. Remove Spring From Electromagnet Valve
    Use a screwdriver to remove the clip and take the valve off. Remove the spring from inside and then replace the valve in place. This will allow gas to flow as usual, but no automatic shut-off to happen.
  4. Test The Device
    You should have now bypassed the thermocouple, and your device won’t shut off if safety features are triggered. Your heater should now turn on immediately without having to wait for 30 seconds.

Maintenance Tips For Patio Heaters

Preventative measures are always best. You can save yourself a lot of time and money by properly maintaining your patio heater and looking after it. This will also help to protect your device and keep it functioning properly for longer.

  • Store the heater in a clean, dry place to stop any damage from rain or the elements.
  • Cover the heater when it’s not in use to stop any dust, insects, or small animals from blocking the heater.
  • Check your hoses for damage every month. It may be worth hiring a professional to do this for you.
  • Check for leaks in your hose and the cylinder, as these are key components within the machine. Again, you may want to ask a professional for help with this.
  • Check air vents for blockages that may stop gas or air from flowing. It would be best if you dusted these out every few weeks.

People Also Ask (FAQ)

How do you unclog an outdoor heater?

The best way to unclog your heater is to use a can of compressed air and blow out the burners.

How much of a thermocouple should be in the flame?

The pilot flame should cover about ½ inch of the thermocouple.

How do you clean a thermocouple on a patio heater?

Start by turning off the propane heater and disconnecting the fuel supply. Use a screwdriver to unscrew it and remove it from the pilot assembly. Rub it down with the rough side of a sponge until it’s completely smooth and clean before replacing it back within the heater.

How long does a thermocouple last?

A properly functioning thermocouple should last at least a few years but will probably need to be replaced after 5 years.

How much does it cost to fix a thermocouple?

It will cost between $150 and $250 to replace the thermocouple within your patio heater.


Your patio heater is a great asset to your home and can be used indoors and outdoors. But it can be frustrating if it suddenly stops working. Thankfully, there’s a lot of common issues which are easy enough to sort yourself at home.

Hopefully, this guide has given you some insight into the common problems and some useful information on how to solve them so you can get your patio heater working correctly again.

Also check our guide on adding a thermostat on a propane heater for controlled temperature.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.