Blower fan cutting out, intermittent

[Soundchasm]

This probably ought to go in the old stove forum, but I hope it's a more universal question.

I've been noticing my blower fan stopping in my old Nashua. Can't say it's related to temperature in any way, just quietly stops running, and then starts back up in a minute. The fan speed control is on the power cord, and that doesn't seem to affect restarting it that I can tell.

The motor isn't screaming or anything. I'd be almost as suspicious of the speed control (rheostat?) as anything.

Any advice on what to check or where to aim my peepers?

Thanks,
Greg

 

[madison]

check the thermostatic coupling on the stove

 

[Soundchasm]

Thanks Madison. This unit is old enough I don't think there's any kind of intelligence built into it. If I get your meaning, a thermocouple would tell the fan the stove is hot enough.

I think it's just a rheostat that varies voltage to control the fan speed. This unit is 40 years old so I don't have any complaints about the service life of any components. Here are some photos.

 

[1750]

My brand new unit was doing exactly the same thing. When I replaced the thermocouple it was fine for months and months without incident.

But it's just started doing it again this weekend. It's odd because it seems to do it for maybe 5 minutes, and then is fine again for the whole day. I'm guessing it will continue to escalate. If it does, I'm probably just going to pull the thermocouple and jump directly from the rheostat to the motor. I did this before when I was waiting for the part, and it works fine.

Good luck.

 

[Beer Belly]

Ours did the same thing....wasn't making good enough contact to the body of the stove

 

[1750]

I made sure this was really wedged. I wonder if somehow it loosens as the box heats up? It's not linear, however, so I guess that doesn't make sense either (it starts fine, gets bad, and then gets better for no apparent reason).

 

[Lumber-Jack]

40 YEARS!
Have you ever removed it and cleaned the dust bunnies out of that squirrel cage fan?

 

[tcassavaugh]

I don't want to wait for mine to come on, so I just set it on manual rather than auto and unplug it when I load. it seemed to take too long to activate, least for me.

 

[Soundchasm]

40 YEARS!
Have you ever removed it and cleaned the dust bunnies out of that squirrel cage fan?

I keep the screen clean and blow compressed air in the cage, but I haven't removed it ever to really look at it. As far as I know, this Nashua is a 70's unit. I did some reading, and the fan is still available from Granger, coincidentally called a Dayton high-temp fan.

I think the other responders have got a temp sensing thermocouple to turn their fans off and on. Mine just has a speed control. So I also looked at rheostats, because that thing would seem most likely to fail.

It's possible the motor isn't the original motor. If I ever get it off, I'll look for any date codes on the motor. Thanks!

 

[begreen]

When was the last time the bearings were oiled?

 

[Soundchasm]

When was the last time the bearings were oiled?

I assumed ownership of the unit in 2002. I admit I've never touched it, but I'll commit to trying to service it soon. I'd hate to risk screwing it up at the peak of the season. I've got a trip out of town this week, but I'll give it a good look when I get back. It's only four screws, right?

In the words of Jeremy Clarkson (Top Gear), "How hard can it be?".

 

[begreen]

Sounds like it is long over due for a clean and oiling. Not too much oil, try about 10-15 drops per bearing.

 

[Soundchasm]

Sounds like it is long over due for a clean and oiling. Not too much oil, try about 10-15 drops per bearing.

I finally read the tag on the back (with purpose this time), and spotted the phrase "Tested 12/78", so none of it's older than 78. The blower will get some attention soon, and I'll poke around for a date code on that thing as well. THANKS.