'Electronic' thermostat. RFI (For info).


We have just replaced a 40 year old 'analog' thermostat that we felt was sticking or not reacting properly, with a simple electronic one.
The new thermostat has a capacity of 2000 watts (in this case a single 1.2 or 1.5 k.watt heater in one 10' by 13' bedroom) and seems to work well enough.
However it creates all kinds of RFI (Radio Freq. Interference) only faintly apparent on a radio some 30 feet away tuned to the 640 kilohertz station we listen to most o the time. But 'roaring' when not on any station! Haven't done any tests at other frequencies yet. e.g. FM.
The thermostat appears to cut in an out at frequent intervals, not the occasional swift 'snap action' of the original one. Then while 'on' it produces a signal with what seems to be a 60 hertz buzz. While installing it looked to be some sort of triac mounted on a heat sink. Seems to a single pole device whereas the original was double pole; or single pole with a second pole for turning it off in the other 230 volt leg?
Very surprised our variuos regulatory authorities, in USA the FCC and the similar authority in say, Canada, allow these interfering devices to be sold? But by same token we have a non rechargeable shaver that emits a god awful racket even when just plugged in. Fortunately it only has short couple of foot range of interference!
Will probably plan to remove the electronic thermostat; seem to recall have a spare 'oldie' thermostat somewhere. BTW, the only repairs we have had to our electric heating since 1970 has been three thermostats, one of which was changed for reasons of 'decor'; and one 20 amp DP circuit breaker. Can't complain about that in comparison to say oil, or gas (not available here), fired equipment .
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terry wrote:

If you have a Johnstone Supply branch in your area, the supplier stocks mechanical electric heat thermostats.
http://tinyurl.com/ylznrwo
TDD
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terry wrote:

Brand name of the 'stat? Use some Ferrite cores.
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Yup. Thanks for the comment might try that; slipping the connecting wires through some ferrite cores, possibly off a computer power cord etc. But irritating is it not that sometheing is not compatible with existing situation?
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Is there an FCC ID# on the new thermostat. A call or e0mail to the company and to the FCC night be in order. FCC Part 15 is probably controlling. I can give you the name of someone at the FCC that might be interested if you contact me directly.
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wrote:

beware of the new furnaces with electronically controlled variable speed blowers for the same reason...
Mark
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