How to troubleshoot tired blower?

[Easy Livin’ 3000]

The blower on my SBI insert (Drolet, Century, Flame Energy, Osburn, Enerzone, etc.) is very weak this season. I took it out and cleaned it thoroughly, saw that the bearings were in great shape, then hooked it back up. It barely blows on high.

Four possibilities as far as I can tell-

1- Rheostat (infinitely variable switch/speed control);
2- Power from the wall socket (less than 120 v);
3-Thermodisc (automatically turns on and off when it reaches a certain temperature;
4- Electric motor.

I'd like some guidance on how to troubleshoot what is the problem. I have a multimeter, and can figure out how to use it, with a little help, I believe.

 

[begreen]

Most likely this is the rheostat. To test, temporarily bypass the rheostat or wire it directly to the 120v line on the bench.

 

[Easy Livin’ 3000]

Most likely this is the rheostat. To test, temporarily bypass the rheostat or wire it directly to the 120v line on the bench.

Beautiful. Easy to test and fix, and not expensive. Appreciate ya, Bgreen!

I noticed that there is something amiss with the rheostat, the speed is lower at the highest setting than it is when it's turned down about 10%.

 

[begreen]

I noticed that there is something amiss with the rheostat, the speed is lower at the highest setting than it is when it's turned down about 10%.

That's a pretty good indication that the wiper in the rheostat is breaking down.

 

[Easy Livin’ 3000]

I looked into replacing the rheostat, $30-40 for direct, on-brand replacement (knob not included, that's another $12). A quick search- fireplace rheostat- turned up a $7 version. Looks to be better quality as well.
Amazon product ASIN B00OICX03U

 

[Easy Livin’ 3000]

Update- I bypassed both switches to go directly to the motor. Both wires were female spade connectors, so I had to be creative to make connection, and a 15 amp auto fuse fit the bill perfectly.

Conclusion- Definitely is the rheostat switch. The blower never blew so hard, even when brand new, so I'm thinking I might have had a stinker from the start, unless there's a limiter (?) in the switch.

Got the replacement ordered for just under $7. I can get the identical switch, now that I'm able to see the specs of the switch, for $10. A little homework saved me about $30, and I now I'm now how it works, which is very valuable to me.

I have to decide whether I want to leave it directly wired, or through the temperature activated snap switch, until the replacement rheostat arrives next week. Nice to get this fixed early on in shoulder season.

 

[Easy Livin’ 3000]

Final update- New rheostat arrives, only glitch was the new one came with two male spade connectors, needed a female to connect to the snap disk. Scavenged a wire from a blown well controller that has two female ends. Blower has never blown so hard, original rheostat must have been faulty.

 

[peakbagger]

Always nice when someone reports on successful fix. Hopefully someone else will learn from it.

 

[Easy Livin’ 3000]

Always nice when someone reports on successful fix. Hopefully someone else will learn from it.

Totally agree. That said, I find that writing things down helps me remember it, myself!

 

[begreen]

We love a story with a happy ending!

 

[davo1028]

I'm also fixing up my blower (Drolet 1400i) and have a quick question for you - how did you remove the vanes from the shaft? Mine are held on by a cylindrical piece with two slots - I can pry it loose a bit with a screwdriver, but can't get the vane to come off when pulling with a pliers while loosening them. Any tips would be appreciated!

 

[Easy Livin’ 3000]

I'm also fixing up my blower (Drolet 1400i) and have a quick question for you - how did you remove the vanes from the shaft? Mine are held on by a cylindrical piece with two slots - I can pry it loose a bit with a screwdriver, but can't get the vane to come off when pulling with a pliers while loosening them. Any tips would be appreciated!

I never disassembled the vanes from the shaft, although I gave that considerable thought, before I decided it was probably an electrical issue, something with the switches.

I'd recommend you rule out the electrical issues before trying to disassemble the "engine".

 

[davo1028]

I never disassembled the vanes from the shaft, although I gave that considerable thought, before I decided it was probably an electrical issue, something with the switches.

I'd recommend you rule out the electrical issues before trying to disassemble the "engine".

Thanks for letting me know! Mine seems to run fine electrically, but is rather out of balance. I'll have to keep playing around with it...