topher@cyb-eng.UUCP (Topher Eliot) (01/30/85)
Well, I smashed into my furnace/AC thermostat one too many times, and now I
have to be ridiculously careful when adjusting it to keep it from coming
off in my hand. So I am considering some sort of smart thermostat to
replace it. I know next to nothing about them, except that they seem to
come in a wide range of prices. I seem to remember reading about one a
year or two ago that would actually "learn" about your house -- you would
program it to have the house warm by 7 a.m., and it would figure out how
early to turn on the furnace in order to achieve this. Does anybody know
about this?
Specific recommendations and/or general advice are solicited. Mail
them to me; I will sumarize to the net if response warrents.
Cheers,
Topher Eliot
Cyb Systems, Austin, TX
{gatech,ihnp4,nbires,seismo,ucb-vax}!ut-sally!cyb-eng!tophersommers@topaz.ARPA (Liz Sommers) (01/31/85)
> Well, I smashed into my furnace/AC thermostat one too many times, and now I > have to be ridiculously careful when adjusting it to keep it from coming > off in my hand. So I am considering some sort of smart thermostat to > replace it. I know next to nothing about them, except that they seem to > come in a wide range of prices. I seem to remember reading about one a > year or two ago that would actually "learn" about your house -- you would > program it to have the house warm by 7 a.m., and it would figure out how > early to turn on the furnace in order to achieve this. Does anybody know > about this? We have onethat cost about 50 dollars at Kmart, an "Energy Saver Thermo" according to what is on the wall. I am about ready to take a hammer to the micro-processor. This thing is just too stupid. You have to reprogram the entire day in order to get ten warm minutes for your shower. I hate them. I am not saving on heat because I just keep it at one comfortable temperature now in order to not have to program the mother. liz
okie@ihuxi.UUCP (B.K. Cobb) (01/31/85)
I went for something less than a "smart" thermostat -- I use a set-back control called the Autostat, made by First Alert (the people that gave Cannon a new lease on life). It's simplistic in its approach -- you can change temperatures 4 times a day Monday-Friday, twice each on Saturday and Sunday. Since I'm not home during most of the day, it does a good enough job for my needs. The Autostat is basically a timer with a motorized drive that moves your temperature control back and forth -- so there's no wiring into the thermostat. (you get used to the noise pretty quickly, and since it only happens 2-4 times a day, it's a moot point). I set it to warm up the apartment about 15 minutes before I get up (68 degrees) and then to set the temperature back just before I leave for work (60 degrees). It brings the temperature up again just before I get home from work, and brings it back down around 11 p.m. Like I said, simplistic -- but it did drop my heating bills about 20% these last couple of months. I'm sure there are some smarter thermostat controls around, but for the price ($35), it's not a bad compromise. It's already paid for itself. B.K.Cobb ihnp4!ihuxi!okie
mstach@ihu1m.UUCP (Dan Hoelker) (01/31/85)
I did quite a bit of checking before I bought a 'smart' thermostat. As stated before the prices vary quite a bit. The main features you probably want to look for are: 1. Number of times per day you can change temperature. 2. If there are separate settings for weekday and weekend. 3. What kind of battery it uses for backup. 4. Ease of programming (User friendliness). 5. Manual override. I wound up getting a Sears thermostat. It is their best one. The list price is 99.95, but they frequently put it on sale for $69.95. It is very easy to program (just enter the time and the temp). It has a door that hides the membrane 'keyboard', and all instructions needed for programming are printed on the door. It has separate settings for weekday and weekend (actually 2 day and 5 day groups, not restricted to Sat and Sun.), which is ideal for us. You can change the temp. 4 times a day, e.g. 2 up and 2 down. If you want to manually change the temperature you can change it any way you want, then at the next time the program would change the temp. it changes. It also has a hold feature, so you can set the temp. and it will stay there until you hit 'run program' (HOLD is printed on the display so you can tell). It uses a 9 volt battery for backup, and defaults to 68 if set for heating and 78 if set for AC if the battery should go out. It was very easy to install. The only feature that is slightly annoying is that the LCD display alternates between the current time and current temp about every 2 seconds. I almost wish they displayed both simultaneously (the temp setting is displayed continuously). One feature that the Honeywell has that the Sears doesn't is that you can set many times to change temp during the day. For some people this might be nice. One problem I heard about the Honeywell (don't know if it is still true) is that it has a special battery that you have to send it back to the factory to be replaced. It also does not have the separate weekend and weekday settings. Dan Hoelker ihnp4!ihu1m!mstach
stewart@ihldt.UUCP (R. J. Stewart) (02/01/85)
I would like to second the opinion of the previous article recommending the top-of-the-line Sear's thermostat. It's very reliable and very user-friendly. Bob Stewart ihldt!stewart
mrl@drutx.UUCP (LongoMR) (02/03/85)
I have something called a "Magic-Stat" thermostat which allows up to 6 setting a day. Each day of the week can be set to different times. The model I have requires that you set it in real time, i.e. you throw a switch to the "learn" position and' proceed to use the thermostat for up to 7 days, changing it up to 6 times/day. The first 24 hour period that is programmed into it will be placed into each day's cycle. Therefore, if I program the thermostat during a 24 hour period, it will repeat the cycle every day. If on a Saturday, or Sunday (or both) I change the cycle by changing the temperature while in the "learn" mods, the thermostat remembers that setting for the particular day of the week. In other words, you can have up to 42 different settings/week. If you change the setting manually when not in the learn mode, the cycle will pick up at the next scheduled temp. change. The thermostat defaults to 68 degrees when in the heat mode and 78 when in a/c mode (power failure with a dead battery, start-up or programming more than 6 setbacks/day) The nice thing about this, tho, is that the thermostat senses the temperature of the room and adjusts its cycle time to have the house at a certain temperature at a certain time. Therefore, if it's cold one morning, the heat will kick on earlier than if it is warmer. There is a new model of the thermostat which includes a clock and intelligent programming capabilities. It also stores two different cycles for summer and winter so you don't have to reset when you switch from heat to a/c. I got mine from JS&A ($79), but I have seen the newer models in the sharper image catalog (I think) for about $89. I have used the thermostat in two different houses for the past two heating systems (no, not at the same time.. I moved) and , aside from replacing a 9V battery after 1 year, have had absolutely no trouble with it. BTW, it appears that our heating bill was reduced by about 30% as compared to using a manual thermostat. I had gas/forced-ar in both homes. M. Longo AT&T Denver
mark@cbosgd.UUCP (Mark Horton) (02/03/85)
I wonder how much your type of furnace affects the savings from these smart thermostats? We have a heat pump, and our manual says that the most efficient thing to do is to leave the setting in one place; that the cost to heat the house back up will be more than the cost to maintain it at one temperature. I'm willing to bet that electric heat strips will be helped by a smart thermostat, perhaps also gas. But heat pumps like equilibrium.
mike@amdcad.UUCP (Mike Parker) (02/07/85)
Mark Horton writes: > I wonder how much your type of furnace affects the savings from > these smart thermostats? We have a heat pump, and our manual > says that the most efficient thing to do is to leave the setting > in one place; that the cost to heat the house back up will be > more than the cost to maintain it at one temperature. I'm > willing to bet that electric heat strips will be helped by a > smart thermostat, perhaps also gas. But heat pumps like equilibrium. I do not understand. I'll not flame and call you names for saying this but I can not understand why it should be so. Do you believe it only because the manual says it is true? Or, can you explain it to one so ignorant as me? Mike @ AMDCAD
joeloda@aicchi.UUCP (Loda) (02/07/85)
I own a Honeywell T8200A thermostat. I selected this model for two reasons:
1 - I felt Honeywell was a reliable brand, plus a friend owns one and
likes it a great deal.
2 - It had the features I wanted.
Some features that it has: Dual setbacks (ie, a "night" setting and an optional
"work" setting). A setback lowers(heat) or raises(cool) the set temperature
while sleeping or at work. It then resets it when you are around. For
example, my settings (heating) call for the thermostat to go to 58F at 23:30,
68F at 06:00 (1 setback), 58F at 07:30 and 68F at 16:30 (2 setback). A
weekend switch (sometimes called a 5/7 day switch) disables setback 2
for any two days (usually Sat and Sun). This model also has a digital clock.
The T8200 tends to be on the expensive side (arround $100); you can
probably find something similar cheaper.
I have no figures on energy savings since I installed this thermostat
right after we moved in.
If you have a heat pump, be careful. From my readings, some heat pumps
should not be used with an energy-conserving thermostat.
Personal note: The "I learn the comfort program" types of thermostats
kind of scare me for some (irrational) reason. Probably something to
do with lack of control.
Joe Loda
Analysts International Corp (Chicago Branch)
..!ihnp4!aicchi!joeloda
--
Joe Loda
Analysts International (Chicago Branch)
(312) 882-4673
..!ihnp4!aicchi!joeloda