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From: cwb@cbneb.UUCP (Bill Brown)
Newsgroups: net.physics
Subject: Re: Question about turning heat off
Message-ID: <207@cbneb.UUCP>
Date: Sat, 25-Feb-84 11:28:31 EST
Article-I.D.: cbneb.207
Posted: Sat Feb 25 11:28:31 1984
Date-Received: Sun, 26-Feb-84 04:58:26 EST
References: <1259@mhuxl.UUCP>
Organization: AT&T Bell Laboratories , Columbus
Lines: 18

A situation where it MIGHT cost more to heat up a cool house rather than
keeping it warm all day is with an electric heat pump/backup resistance
furnace system.  Those that work like mine automatically kick in the 
resistance unit when the house is some amount cooler than the set point.
When you turn the set point up to warm up the house the dumb system thinks
resistance heat is needed.  Because the resistance furnace is much less
efficient than the heat pump (at reasonable temperatures) there are probably
conditions where more total electricity would be used.  This reason would
not apply, of course, if you have any other type of system or a more 
intelligent control system.  But there might be other effects (Ideas anyone?).

By the way, in very cold conditions, do you have to worry about the house
getting too cold for your house plants or, at the extreme, for your
water pipes?   What is the effect of temperature cycling on the house itself
(wall cracking, for example) or on its contents (furniture, elctronic gear)?

					Bill Brown
					cbneb!cwb