Fan Speed Physics

[WarmGuy]

The fan on my Regency Warmhearth has two speeds.

Do you think the high speed is significantly more effective than the low speed? That is, at low speed, the air will move more slowly, but it will have more time to get heated up as it moves around the firebox.

Is it possible that a low speed is almost as effective in terms of heating the room as a higher speed?

 

[mellow]

Base your fan speed on how hot you are running the stove, if you are running it hot then high, if running it cooler then low will work fine.

 

[Hollywood]

The fan on my Regency Warmhearth has two speeds.

Do you think the high speed is significantly more effective than the low speed? That is, at low speed, the air will move more slowly, but it will have more time to get heated up as it moves around the firebox.

Is it possible that a low speed is almost as effective in terms of heating the room as a higher speed?

I don't think it is going to make much of a difference on the temp of your stove once it reaches the high point of which you have your heat set at. I have a PDV 25 and when i first start it i have the room blower on 1 till it heats up then i turn it on 9 ..And with you only having 2 settings i would think it's close to my 1 and 9 setting which don't seem to make the air any cooler on 9 .

 

[WarmGuy]

I'm considering replacing the existing (noisy) fan will a much smaller, quieter unit.

I'm thinking that even if there's much less airflow, the air that flows through will be hotter. Therefore the efficiency of the heating will not decrease as much as expected.

For example: Airflow cut by 50%, efficiency cut by only 20%.

Is my reasoning faulty?

 

[Slacker]

Take a meat thermometer and place it in one of your vents on your car. Play with the fan speed and you will see how much velocity affects heat transfer.

 

[Hollywood]

I'm considering replacing the existing (noisy) fan will a much smaller, quieter unit.

I'm thinking that even if there's much less airflow, the air that flows through will be hotter. Therefore the efficiency of the heating will not decrease as much as expected.

For example: Airflow cut by 50%, efficiency cut by only 20%.

Is my reasoning faulty?

It depends on the area your heating..I'm heating a 1900 sq ft house so i need a lot of air flow , if your heating 1 small room you could use less air flow..

 

[begreen]

Also depends on the house layout and stove location. With an open floorplan and centrally located stove we only run the blower when it's very cold outside or when we need quick heat. Otherwise natural convection does a good job of distributing the heat pretty evenly.

 

[Pellet_Pete]

It depends on the area your heating..I'm heating a 1900 sq ft house so i need a lot of air flow , if your heating 1 small room you could use less air flow..

Also depends on the house layout and stove location. With an open floorplan and centrally located stove we only run the blower when it's very cold outside or when we need quick heat. Otherwise natural convection does a good job of distributing the heat pretty evenly.

Good replies - the amount of convection is certainly the primary aim of fan speed. My little Jotul can heat the whole 1300 sq. ft. on a 30-40 degree day w/o a fan due to its centralized location, but my Harman XXV (pellet) is in an awkward corner room which requires the built-in blower PLUS a large circulator fan to "push" the heat out into the body of the house.