anyone ever balance the airflow on a furnace?

[john hd]

Originally posted by Mariner
Hi all,

Have just read the above thread with interest. The furnace fan motor is a DC motor. Can dc motors slow down due to brush wear? Just a thought. maybe the fan intake is partly restricted with dust buildup or slowed down due to the dirt build up.

My thought would be to remove the fan motor - if possible and clean and replace the motor brushes. Can't do any harm and it might just make it work better.

Mariner

the fan runs quite well and moves alot of air, just not to the rear.

i'll look at the ductwork next time i'm up hunting.

really think it is the unequal length of the ductwork.

john

[Sav'h Steve]

John,

I ordered a half doz 12 volt fans that I put around the trailer. I also put resistors on all the existing fans except the heater.

One fan I mounted on the ceiling right behind the hall light and fed the 12 V from that light and installed a small switch on the end of the light for the fan - (So I can run either or both.)

My idea was when I am air conditioning the coach and the exhaust fans are closed, this little fan would help move the cold air back to the bedroom area.

I think the same would apply for the heat.

This could be an addition to straightening the hose to the rear for smoother airflow & heat.

(BTW - I think on the next coach I may use 24 volt fans so they will go at half speed and not use resistors.)

Steve in Savannah....

[john hd]

steve

i already employ that idea when running the a.c.

got a small fan at wal mart with a clip on it, 12 volt with a 9 foot cord. less than 10 bucks.

i plug it into the rear tv outlet and clip it to the top of the room divider. it moves enough air to evenly cool the trailer.

i'm sure i can do the same when heating.

my main concern would be the tanks as brett pointed out. i have never had freeze problems down to 10 degrees.

right now my trailer is fully winterized so the tanks are not a problem.

i did notice if i run the heat strip and fan on the ac in tandem with the furnace the whole trailer is more evenly heated.

really it is just a minor problem, i think the louvered vent outlet is the way to go. very inexpensive fix. in addition to checking the vent hose route.

john

[Chas]

I am not sure how they did it but on my Overlander somehow critters had gotten into the belly. They pulled insulation up thru the belly heat pipes into the main heat duct and had a few cozy little nests in the mid section of it, effectively plugging it up. I was told that there are screens to prevent this from happening but nonetheless it happened to me.

Even with a clear duct, the output at the rear bath grille is very minimal. I think it is just a bad design, the furnace should be more centrally located.

Chas

[John]

John,

My furnace has 6 duct outlets:

2 - 3" coming out the side into the living room
2 - 2" coming out the back that goes to the holding tanks
2 - 3" coming out the side that runs to bathroom & bedroom

I had two leaks going to both the bedroom and bathroom. One was with the connecting coupler and the other was a tear underneath the duct.

John