ATN: Electronic techs, gerus, techies, etc.

[kd460]

I know there is a product out there (or was) that could be connected to your standard furnace (gas forced air) that would turn the blower motor on at a scheduled rate regardless of the temperature. I assume it is some type of a timer which triggers a relay or sends a signal via the thermostat to turn the blower on for say 10 minutes every hour (or whatever you program it to be as far as interval and duration).

If I remeber correctly, it was like $60 bucks. While not too bad of a price, I was thinking that it would not be too tough of a DIY project for those who have some basic electronics/circuit/soldering knowledge. I can't see more than $20 in components.

While I know a little about electronics, I do play around with it a little as a hobby. I know basic electronic components, their functions, and can read basic schematics.

I was hoping someone in the "know" would have some ideas on the type of circuit I just described. Something based on a 555 timer (or similiar) and a relay for the 24 volt system that would trigger the blower on a furnace for a period of time at regular intervals.

I know there has been discussion here in the past about the benifits vs disadvantages of using the blower on a furnace to move air around, but I know for a fact in my home with my layout, it does help distribute the heat a little better and even out the temperatures some. I agree it does not serve much advantage running the blower on a continous basis, but at periodic intervals, it does help my situation. I do turn on the blower from time to time when the room where my burner is way too warm and the other end of the house is too cool. I would like this to happen automatically when I am sleeping

So, any ideas on a circuit, or even something simple that I am not aware of (didn't think of) to acheive this? Might be something fun and benificial to come up with. KD

 

[tkirk22]

It's a repeat timer circuit.

This may help:
http://www.reuk.co.uk/Repeat-Timer-Circuit.htm

Why not just activate the furnace blower when the stove room gets too hot? I'm thinking of adding a second thermostat that just activates the fan rather than the central air. Or is there an easier/better way?

EDIT: I was just thinking about this a little more. How about a second electronic thermostat so you can keep the stove room a little warmer during the times people are likely to be in there and then at night it can have the fan come on at a lower temperature.