Gas Fireplace Blower Guide: Common Issues and Fixes

Is your gas fireplace blower not blowing air? This guide covers common problems, troubleshooting steps, and when to replace or repair the blower.

Gas Fireplace Blower vs No Blower

Gas fireplaces usually come from the factory with no blower. The fireplaces will heat with no blower, It’s called radiant heat. If you add a blower you are pulling in unfiltered air and collecting dust and debris in the control section of the fireplace.

You bought a new home or moved into a rental that has a gas fireplace. Nice! But when you go to turn it on you can’t find a thermostat. All you see is a regular was switch next the the fireplace. You switch it on and the flame comes on.

Well, that’s simple enough. But now, when you get warm, you have to go and turn it off. Not very high tech. And then you notice that the gas fireplace blower won’t turn on. Maybe the fireplace blower thermostat is bad, or maybe there is no gas fireplace blower. , What’s with that?

The builder was on a budget and the only way to turn on your gas fireplace is with a two dollar switch on the wall next the fireplace. Seldom do new home owners think to consider bargaining with their builder or real estate agent for the upgrades that are available.

I met a customer at his rental home because the new tenant said the gas fireplace blower wasn’t turning on. When I opened the compartment below the fireplace and shined my flashlight in to have a look, there was no blower there.

The thermostat was non existent. It had the two dollar switch on the wall. So the landlord just kept quite after saying “well, that’s how they come”.

Yes, that’s the way they come when you don’t know how to ask or what to ask for.

Their are some simple and relatively inexpensive solutions and these can be an easy DIY project.

A gas fireplace can be a beautiful amenity to a home, but the stripped down versions don’t have, nor do they require a thermostat or even the blower to work.

Without a good thermostat type of control you are left to remember (or forget) to flip the switch to either turn on or off the burner when you come and go.

Kind of like my garage door when I’m a couple of miles out of town and just happen to think of whether or not I remembered close the door when I pulled away.

A Few Solutions For Adding A Thermostat To A Gas Fireplace

First make sure that your fireplace has a millivolt valve. Yours should look similar to the image below. If not, do some more research before attempting any modifications like adding a thermostat.

Working with millivolts means that the valve is powered by the pilot flame burning on a pilot generator or thermopile. It creates a very small voltage that you wouldn’t be able to feel should you touch the wires with the pilot lit.

Be safe though by using general safety procedures and turn off all gas and power before working on any appliance.

Look for owners manuals or wiring diagrams that explain the voltages to your fireplace. Above all, be safe, call a professional if you have any doubts.

Thermostat wire connections are circled in white. The red portion of the valve also has markings that are labeled “TH” for THermostat. These connections are not polarized, there is no positive or negative connections like on a car battery.

TP is for thermopile. Thermopiles have two wires that do have polarity. Powerpile wires are red and white generally. The red is + positive and the white is – negative.

When connecting a thermostat it is not necessary to worry about positive or negative because the thermostat is just a switch. Don’t even worry about wire colors since there are only two wires from the thermostat.

The powerpile is connected to the top TH and the middle connection marked “TP” for thermopile.

The simplest and quickest answer for converting to a thermostat is to just replace the switch with a millivolt thermostat.

The image above is from my own fireplace insert. It can literally be this easy. Thermostat wire is generally 18 gauge wire and two conductors is all that’s needed.

Because pilot generators or powerpile create such a low voltage, all connections need to be clean and tight. Also, do not use one of these budget thermostats that say they work for both 24 volts and millivolts. You will have trouble.

You can quickly recognize a 24 volt thermostat by the anticipator inside or under the stat cover.

These 24 volt thermostats come in various configurations. Just look for a scale with numbers that range from approximately 1.2 down to .25 or so. Don’t use one of these thermostats.

Look for and find a thermostat that is for millivolts only. If your project has a limited budget the Amazon has the stat and you can find it here by clicking on the button below. And for less than 30 bucks. Shipping varies, of course.

This stat comes with an off position, which could be appropriate. Not so if it’s the only source of heat.

Leaving thermostats in the off position in areas of the country that have extreme weather can be an invitation for frozen and broken pipes.

Another option for millivolt thermostats is a digital stat or even a programmable thermostat. Just check to make sure that it’s millivolt rated. Pick from most any that look good. The larger the display the easier the are to see.

Digital thermostats will likely require batteries. Batteries for this type of stat will last about a year, maybe longer. I would use the basic stat above unless you feel you want a program to turn the fireplace on and off with a schedule.

Some people just love schedules. I am at that time in my life that I run from schedules and appointments.

Easy Idea For Addition Of A Gas Fireplace Blower

Just recently added one of Durablow’s blower kits for a natural gas stove. The button below is a clickable link to Amazon, should you be interested in recent prices and availability.

It was a plug and play unit, at least for this installation. The rubber isolators on the bottom helped keep the fan quiet and on the back were magnetic strips that helped to hold it in place against the back.

I inserted from the front with a little wiggling around while being careful not to knock of any wires or other things.

The switch that came with that turns on the fan with heat from the burner box mounted easily under the burner with provision already made for a switch.

The dial, a combination off and fan speed potentiometer mounded on the side just inside the access door for easy adjusting.

Wiring was a piece of cake with easy to follow instructions with the kit. Make sure that what you get will fit. But in today’s market, everyone is making it easy with returns and refunds.