How to troubleshoot gas fireplace that won't light

By Stephanie Snay with Angie's List – In the mood for chestnuts roasted on an open fire, but the gas fireplace won't light? Bummer! Failing fireplaces can ignite your anger, but don't lose your cool just yet.

Highly rated experts recommend trying the following techniques to make your fireplace go up in flames... in a good way.

1. Pilot light systems are the most common reason gas fireplaces fail to light, according to Justin Worthen, outside coordinator of Alpine Fireplaces, located in various cities in Utah and in Boise, Idaho. Check the main gas valve to make sure the gas is turned on.

2. If the gas is on, and the pilot hasn't been lit in a couple months, you'll need to purge the air out of the pilot tubing, says Steve Alleyne, owner of Firefixer in Chicago. To do this, hold the pilot button down for about one to three minutes while the air bleeds out.

Worthen adds that spiders and other insects often lay nests inside pilot tubings in rural areas. "We suggest people in rural areas leave their pilot lights on for this reason," Worthen says.

3. If gas is coming out of the pilot, but it still won't light, the spark igniter could be the problem. Alleyne says to look for and clear out any debris between the igniter and thermocouple.

4. The pilot lighting, but not staying lit, indicates that the thermocouple is worn out, Worthen says.

5. Another quick fix to try, according to Alleyne, is blowing compressed air into the pilot area, waiting a couple minutes, then trying again — just like you did with your Nintendo games in the '90s.

Other issues include loose connections, defective valves or bad modules in electric ignition units, according to experts.

Worthen adds the newer electric systems are more sensitive, and require the consumer to figure out if the issue lies in the electronic ignition or pilot.

He says sometimes those units have a battery backup system and can be switched to battery mode. However, diagnosis methods remain about the same. Worthen says most service calls are about $100, and repairs for pilot lights cost $150 on average.

How much you choose to investigate your fireplace problem is dependent on your experience with gas appliances, according to Alleyne. You're better safe than sorry. "A small repair can become much more costly if you don't know what you are doing," he says.

If you've attempted all the troubleshooting methods that you feel comfortable with, it's time to call in an expert. "You may find a low priced handyman, but beware, gas fireplaces operate differently than your furnace," says Alleyne, who charges $145 to inspect, clean, service and repair a fireplace, and offers a 10 percent discount to Angie's List members. "You're better off with a specialized technician."

Angie's List guide to fireplaces

Click here for more information from Angie's List