Replacement Time for Convection and Combustion Blowers
How long do blowers last in a pellet stove?
I had a customer who was a tinkerer. We were talking about the longevity of blower motors and he wondered how long his Englander exhaust blower would last. I told him about my failed experiment and that’s when he took from his pocket a calculator. He studied the blower. Quickly, he surmised that the fail point or “weakest link” would be the bearings that keep the motor’s shaft centered and spinning. Using some of the technical data from the motor and a few calculations, he arrived at a number…43,000. That’s the maximum number of load hours he determined this blower could run before it quit and needed to be replaced.
If we do the math backward, 43,000 hours divided by 24 hours in a day equals 1791 heat days. Here in the northeast, we have about 190 heating days a year; 1791 divided by 190 equals 9.4 years of use. We agreed this was the best case scenario for a combustion blower and assumes no other contributing factors such as excessive overheating, corrosion or improper maintenance. As it turns out, most of the blowers I replace are in fact about 10 years old.
Can I replace my existing blower with something more efficient or higher quality?
Yes, but it really depends on the stove you have and the quality of the OEM blowers that came with the stove. Top names, such as Quadrafire and Harman are made with top quality components out of the factory. Budget pellet stoves, commonly purchased online or in box stores, often have a cheaper version of the best OEM blowers. When we source an aftermarket alternative, we are generally seeking a reproduction of the better quality blower and adapt it to the lesser quality stoves. In this situation, yes, there is a better quality blower available.
For example, Englander’s PU-76002B exhaust blower is made by Fasco, but it’s not nearly as good as the Fasco 12050011 exhaust blower used on the Lennox brand of Whitfield stoves. The OEM blower from Englander is a low budget blower modeled after the top quality OEM alternative. These two motors have the same technical specs, but the Lennox blower will last much longer and remain much quieter over a longer period of time.
Our aftermarket made by NBK, part number AMP20061, has the same specs as the Englander OEM but has a quality build more like the Whitfield. Best of all, our aftermarket part costs 36% less than the Englander OEM and 57% less than the Whitfield OEM.
My stove doesn’t put out as much heat as it used to, is this a convection blower problem?
The most important thing to know about convection blowers is that they circulate the room air. All of the dirt, pet hair, dander and other airborne material in the room air will pass through this blower and will collect at various places on the stove, not to mention the blower itself. If you are suspect that your blower isn’t circulating enough heat, start by inspecting these areas and remove obstructions that will have accumulated in the stove and blower. Convection blowers come in many different shapes and sizes and draw room air from many places in and around the stove. Proper maintenance if this blower involves accessing the blower and making a visible inspection a couple of times each year.
Centrifugal blowers have one blower wheel inside of a casing with an opening on one side of the housing as an air inlet. If there is a screen on this opening make sure you inspect it and clean it off periodically. A lot of debris will collect there but your blower wheel will remain somewhat clean. If you do not have a screen, the blower wheel itself will collect debris. The blower will need to be removed, cleaned and reinstalled.
Tangential blowers are long and will have the motor that drives the wheel located on one side, usually closest to the side wall of the stove. These blowers do not have screens and usually do not spin very fast. This makes them quieter than centrifugal blowers but they aren’t as powerful from a horsepower standpoint. It doesn’t take much debris in the fan blades to slow down the blower and because of this, they should be cleaned with a brush and vacuum at least once per year.
Aside from age, what are the signs that a blower needs to be replaced?
If a bearing inside of the blower is starting to wear, you’ll hear it. Usually, the sound will be more noticeable when the blower first comes on and will get may quieter the longer the stove runs. Eventually, the bearing will seize and the blower will start to slow down or stop working altogether. If this happens with the convection blower, your stove will overheat and shut down. Often, the high limit switch that shuts the stove down will need to be manually reset. If this happens with the combustion blower, the blower will shut down and smoke will fill the stove or the room. If your stove can report errors, you’ll see a vacuum error. Either scenario, your blower needs to be replaced.
If your blower is vibrating, buzzing or humming, the coil is getting weak. This will cause the blower to slow down at full speed and possibly even stop turning on low speeds. Your blower needs to be replaced.
At any time, if your blower wheel cannot spin freely by hand when the power is off, the blower needs to be replaced.
Are the blowers inside of wood stoves and gas stoves the same as pellet stoves?
Yes, but there is usually only one convection blower on a wood stove or wood insert, if there's a blower at all. There are generic kits or this Eco Fan if you want to add one, this can be done to just about any wood stove, however; wood stoves made today will have an optional blower for circulating room air. Most wood inserts, because they are fitted into the fireplace, will have a convection blower of some sort.
Gas stoves and inserts vary by make and model. All will have a convection blower. Some gas stoves and inserts have power vent blowers that are affixed to the outside of the home and will be model specific.
What about my Pellet Grill convection blower?
Just like pellet stoves, pellet grills need a blower motor to operate, albeit for a different reason. This blower helps circulate air into the grill and push smoke around and out of the exit hole to keep consistent temperatures. If you've noticed uneven cooking on your meats, unsteady temperatures, or a lack of smoke flowing out of your grill, it's time to replace the convection blower. Some of the more popular pellet grill brands with convection blowers include Traeger, Pitboss, and Louisiana Grill.