Furnace doesn't always light
Is there a good thread for troubleshooting furnace problems? Mine is not quite 3 years old and has worked fine until this week. Sometimes when the thermostat calls for heat the fan comes on but the...
Forum Discussion
If the sail switch is being indicated it very likely is NOT the problem (I will not say it can not be the problem but)
Here is what happens: THe blower is supposed to move air, the sail switch senses the movement of the air.
Now, in every floor register system I've ever seen the regesters fill up with "Crud" you need to pull the registers and vacuum the ducts out.. One of those "lint lizard" hose adapters (this is a small hose that slips over the larger hose of your vacuum to suck lint out of dryer vents and such) may be of assistance, though I've never used one myself.
In addition the fan can get "old and tired" though at 3 years.. i think not.
Wires to the fan can get "old and tired" this in fact happened to me on a different circuit.. Short version.. Open circuit voltage was good but put any kind of a load on it and 10-9-8-7-6-5-4-3-2-1-0 went the voltage very fast (as load increased from a LED to a small incandescent).This, in fact, is the other reason I prefer a test lamp (Incandescent) over a volt meter for trouble shooting.
There can be other obstructions to air flow.
And low battery voltage causes low fan speeds.
Here is what happens: THe blower is supposed to move air, the sail switch senses the movement of the air.
Now, in every floor register system I've ever seen the regesters fill up with "Crud" you need to pull the registers and vacuum the ducts out.. One of those "lint lizard" hose adapters (this is a small hose that slips over the larger hose of your vacuum to suck lint out of dryer vents and such) may be of assistance, though I've never used one myself.
In addition the fan can get "old and tired" though at 3 years.. i think not.
Wires to the fan can get "old and tired" this in fact happened to me on a different circuit.. Short version.. Open circuit voltage was good but put any kind of a load on it and 10-9-8-7-6-5-4-3-2-1-0 went the voltage very fast (as load increased from a LED to a small incandescent).This, in fact, is the other reason I prefer a test lamp (Incandescent) over a volt meter for trouble shooting.
There can be other obstructions to air flow.
And low battery voltage causes low fan speeds.
