From: pdesalis@bnr.ca (Peter de Salis)
Subject: Re: Honeywell Electronic Thermostat
Organization: Bell-Northern Research, Ottawa, Canada
Date: Mon, 4 Jan 1993 20:35:12 GMT

In article <1993Jan3.175152.24955@primerd.prime.com> mguyott@eriador.prime.com (M. Guyott) writes:
>In article <1i4t5nINNq4i@usenet.INS.CWRU.Edu> wb8foz@skybridge.scl.cwru.edu (David Lesher) writes:
>> I recall others recently recommending a specific Honeywell
>> model that 'learned' how long it took to heat your house, and
>> reacted accordingly. I think it was a Chronotherm III, or such.
>> My query is directed to those who have purchased it.
>>
>> a) What's the correct name?
>> b) What did you pay for it, and where?
>> c) How long a warranty did it come with?
>
>I recently purchased two of these beasties.  Here is my experience.
>
>a) Correct name:   T8602A, T8602B, T8602C, or T8602D at least if you want
>                   to program the weekdays with one program and each
>                   weekend day with separate programs.  These are the ones
>                   I purchased.  I believe the T8600 line has only one
>                   program that is used for all seven days.  You will have
>                   to check this yourself.  I believe that the A and B
>                   models are for heat only systems.  The A model gets its
>                   power from batteries.  The B model draws its power from
>                   the furnace.  The C (batteries) and D (furnace) models
>                   are for heat and AC applications.

Honeywell has recently introduced (here in Canada) a line of thermostats
that seem to be somewhere between the cheap comsumer models and the
'trade' models.  In September, I purchased a 'MagisStat 34' from Beaver
Lumber.  Here are the details:

Model: CT3400A
Features:
  - heat/cool plus fan switch
  - 3 programs (weekday, Saturday, Sunday)
  - 4 different settings per program
  - Adaptive Intelligent Recovery
  - run by batteries (3 AA cells)
  - adjustable for elctric, gas/oil warm air, water and steam heating
  - display in deg C or deg F, 12 or 24 hour
  - temporary override
  - temperature hold (semi-permanent override)

>b) I payed $140.00 for each T8602C thermostat that I bought.  I purchased
>   them through my electrician who said he bought them at Graingers for
>   the price he charged me.  I believe him.

Price: C$90

>c) According to the documentation that came with the stat they have a one
>   year warranty.  But according to the folks at Honeywell the warranty
>   is actually five years.  I do not have anything in writing about the
>   five year warranty.  Only what I was told over the phone.

I don't remember how long the warranty is.

>The older T8602s used a recovery algorithm that was suited to 2 stage heating
>and cooling systems (i.e. heat pumps).  This algorithm unneccesarily cycled
>1 stage heating equipment on and off.  As of the 27th week of 1992 they
>began making the T8602s so that they no longer unneccesarily cycle the heating
>equipment for 1 stage heating systems on and off.

My CT3400 was made on 9210.  The way that AIR is described in the
owner's manual, it does not stay on first thing in the morning until
the house is warm, rather, it runs the furnace for a while (15 mins?),
then shuts it off for a couple minutes, then starts it up again.  They
claim that this helps avoid the 'overshoot' common when trying to warm
the house up by several degrees.

I really liked this feature until my furnace was condemmned (cracked
heat exchanger), and I bought a fancy two-stage one.  The new furnace
starts up with the burners on 'low'.  If after 10 minutes the
thermostat is still calling for heat, the burners switch to 'high'.  I
find that the cycling that AIR wants to do makes the house heat up too
slowly.  It would be nice to disable this part of the AIR algorithm
(using a switch on the back would be perfect).

--
Peter de Salis                          Email: pdesalis@bnr.ca
Bell-Northern Research, Ltd.            Phone: +1 613 763 3811
Ottawa, ON
Canada                                  Opinions are mine, not BNR's.
Newsgroups: misc.consumers.house