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Electric heat-locating faulty relay

How can I locate a faulty relay (silent operator) for electric heat? I have electric heat in my house, each room on it's own breaker in the garage. One room now bakes at around 83 degrees and will only shut off if the breaker is switched. I replaced the room's thermostat with one from another room that I know works and the same thing happened. My electrician is leaving town for 3 months, but brought over a new relay, which he said is most likely what is needed. However, we were unable to find where the old one is. The room's cable from the breaker switch in the garage is visible for about 10 inches and then disappears under insulation. Checking where the other cables come out through the basement does not reveal that particular one anyway. I've removed the basement insulation near the (sheetrocked and paneled) room with the problem but there's no sign of the cable. I explored the baseboard heaters, but no luck. Two questions: Is there a tool that can help trace the cable to locate the faulty relay? Is it possible to ignore the faulty relay and install one near the breaker box where the cable is obvious? Any help would be greatly appreciated.

Re: Electric heat-locating faulty relay

Have you tried removing the #14 or #12 black or red wires from the room thermostat? If it's "line operated" like most there is no relay. Mark all wires, so they may be replaced. If lifting the wires makes the heater turn off, replace it.

If you really have a relay lifting the small wires off the thermostat should drop out the relay and the heat will go off unless the relay contacts are "welded" closed.

You can pick up a pencil like chirper from Home Depot or Lowes for about $15 which will light and chirp if held near a piece of energized (insulated) wire.

If you turn off the "juice" to the bad relay and it gets buried in insulation you may be able to locate it again with the chirper by turning the breaker off and on.

If you have a "smart house" the relay is proably in a main panel with a bunch of wires going to it and a dozen relays. Look in the attic or basement.

Re: Electric heat-locating faulty relay

There's more discussion in his other thread .........

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