On Tue, 2007-10-02 at 12:50 -0600, Frank Cox wrote: > There are also some weird effects that can be created by hooking devices from > different circuits together. I know that the electrician here had to do some > fancy stuff to make my air conditioners and the zone valves on my hot water > heating system work properly as they run on different circuits. It ended up > that there was no easy way to use a single thermostat in the rooms, even though > the devices would never be on at the same time and even though the thermostats > physically switch from "cool" to "heat" so you wouldn't think there would be a > conflict. "Ice-cube" (little small block looking) relays would do the trick. They just won't look very nice unless you hid them up in the attic or under the house ... wherever your primary control wiring runs. If I remember correctly, white = heat, green = fan, yellow = cooling, with red as common. Better check that. The thermostat would nicely control the 24v coils to the relays and the contacts to the relays don't care what the voltage is or the transformer source (which might have been your problem, multiple 24v transformers, ie: old boiler system with new package unit AC) is used to close the Heating / AC / Fan circuits. It would be really strange for them to not be 24v. Yup, some small relays would have fixed that sho' nuff. Ric -- ================================================ My father, Victor Moore (Vic) used to say: "There are two Great Sins in the world... ..the Sin of Ignorance, and the Sin of Stupidity. Only the former may be overcome." R.I.P. Dad. Linux user# 44256 Sign up at: http://counter.li.org/ http://www.sourceforge.net/projects/oar http://www.wayward4now.net <---down4now too ================================================
