On Sunday, November 15, 2015 at 6:55:03 PM UTC-5, Ralph Mowery wrote:
"Chicago Bob" wrote in
message oups.com...
I don't need a complex programmable thermostat. All I want is to know how
many hours that fan has run so I know when to change the air filter. The
fan runs frequently in the summer and winter, but very infrequently in
the spring and fall. How often the fan runs is determined by temperature.
You can go weeks - or months - without the fan running at all.



You need to put a run time meter on the fan motor.

Get one like this from China. I have ordered several items from China and
it usually takes 2 to 3 weeks. They all have worked fine.

Ebay number:
111229090029

What purpose will a run time meter serve, other than recording the run time?

His goal is not attainable unless he can keep the amount of dust being trapped
by the filter constant over any given fan run time. That ain't going to happen.

Methinks he knows that. He's just being silly.