Winter is upon us,27&unit=3Diformatting link
> (unfortunately there's no snow so the frost is going deep).
>
> We have an outdoor, above ground insulated cistern that
> we heat with a 120Vac sump pump that's works well.
>
> The problem is it's manually controlled, which is inconvenient
> when we leave for a week or two...
>
> So we need a thermocouple (thermistor) we put into the
> cistern and cycle it to keep the water temperature at 40F.
>
> Is there something on the market that can do that, I've looked
> and haven't found anything yet.
> If not, I'll design and market one.
> Ken
We use a small heater to keep the dog water from freezing in the winter time. (Silly dogs like to sleep outside.) They make bigger ones for livestock troughs. Try at some farm supply store.
George H.