On Sun, January 8, 2012 2:39 pm, Carl Denk wrote:
> I have a standby 240 volt electric resistance furnace with 24 VAC
> controls. Since the electricity costs are large, and usage due to some
> minor item failure on the main fuel supply, I am looking for an brief
> beep audible warning when the unit is powered up. The sound should be
> very brief (maybe a second or less), not an unpleasant tone or high
> volume. The unit is in the basement, and should be able to hear it on
> the 1st floor. This should be just barely heard, so as not to startle,
> or might even choose to ignore for the moment. Cost not a priority since
> this is one off.
>
> I have thought of using a 555 timer, with a rectifier bridge and a 78XX
> regulator off the 24 VAC circuit and a sonalert sort of noise maker.
> Also have thought of a relay that opens it coil circuit when energized,
> and then something to keep the circuit open until next furnace usage.
>
> Any thoughts would be appreciated, and thanking in advance. :)

If the thermostat for the Electric Resistance Furnace is on the first
floor, why not something that detects current in the lines that close when
the furnace is on?  My heat pump has an LED that lights up when the
auxiliary coils are in use- in a darkened hallway, I've found that an
indicator light is pretty obvious. Plus the light could be on continuously
as a reminder, not just when it cycled.


Matt Bennett
Just outside of Austin, TX
30.51,-97.91

The views I express are my own, not that of my employer, a large
multinational corporation that you are familiar with.
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