Why Won't My Outdoor Propane Heater Stay Lit?

Outdoor propane heaters are essential for enjoying your outdoor space during colder months. However, it can be frustrating when your heater won’t stay lit. In this comprehensive guide, we will explore the possible reasons why your outdoor propane heater won’t stay lit and provide advanced hands-on details and technical specifications to help you troubleshoot the issue.

Possible Causes

1. Dirty Thermocouple

The thermocouple is a safety device that shuts off the gas supply when the pilot light goes out. If the thermocouple is dirty, it may not detect the pilot light, causing the heater to shut off. The thermocouple is typically made of copper or iron and is located near the pilot light. It generates a small electrical current when heated, which is used to keep the gas valve open, allowing propane to flow to the burner.

2. Faulty Thermocouple

If the thermocouple is faulty, it may not generate enough electricity to keep the gas valve open, causing the heater to shut off. The voltage output of a functioning thermocouple should be between 20-30 millivolts (mV) when the pilot light is lit. If the voltage output is below 20 mV, the thermocouple may need to be replaced.

3. Blocked Gas Valve Orifice

The gas valve orifice is a small opening in the gas valve that regulates the flow of propane to the burner. If the orifice is blocked, it can prevent propane from reaching the heater head unit, causing the heater to shut off. The orifice size can vary depending on the heater model, but it is typically between 0.8 to 1.2 millimeters (mm) in diameter.

4. Air in the Gas Line

If there is air in the gas line, it can prevent propane from reaching the heater head unit, causing the heater to shut off. This can happen if the gas line has been disconnected or if the propane tank has been refilled. The gas line should be purged of air by opening the gas valve and pressing the igniter button until the heater lights.

5. Loose Connections

Loose connections in the gas line or regulator can cause gas leaks and prevent the heater from staying lit. The gas line connections should be tightened to a torque of 15-20 Newton-meters (N-m) using a torque wrench. The regulator should also be checked for any signs of wear or damage.

6. Worn-Out Ignitor

If the ignitor is worn out, it may not produce a spark strong enough to ignite the gas, causing the heater to shut off. The ignitor should produce a visible spark when the igniter button is pressed. If the spark is weak or non-existent, the ignitor may need to be replaced.

7. Low Gas Pressure

If the gas pressure is too low, it can prevent the heater from staying lit. The gas pressure should be between 11-14 inches of water column (in. w.c.) for natural gas or 10-14 in. w.c. for propane. You can use a gas pressure gauge to check the pressure at the regulator.

DIY Troubleshooting

Here are some steps you can take to troubleshoot why your outdoor propane heater won’t stay lit:

Check the Thermocouple: Remove the burner assembly and check the thermocouple for dirt or debris. Clean the thermocouple with a soft cloth or brush. If the thermocouple is faulty, you may need to replace it.
Check the Gas Valve Orifice: Remove the gas valve and check the orifice for debris or blockages. Clean the orifice with a small wire or brush. If the orifice is blocked, you may need to replace it.
Check for Air in the Gas Line: Open the gas valve and press the igniter button. If the heater does not light, turn off the gas valve and wait a few minutes for any air in the gas line to dissipate. Then try lighting the heater again.
Check for Loose Connections: Check all connections in the gas line and regulator for tightness. Use soapy water to check for gas leaks. If you find any leaks, tighten the connections or replace any faulty parts.
Check the Ignitor: If the ignitor is worn out, you may need to replace it. You can test the ignitor by touching it with a metal object. If the ignitor is working, it should produce a visible spark.
Check the Gas Pressure: If the gas pressure is too low, you may need to replace the regulator or hose. You can test the gas pressure with a pressure gauge.

By following these steps and using the technical specifications provided, you should be able to identify and resolve the issue with your outdoor propane heater. Remember to always prioritize safety when working with gas-powered appliances and consult a professional if you are unsure about any part of the troubleshooting process.

Why Won’t My Outdoor Propane Heater Stay Lit?