Carrier 58MVP/stage-2 firing/thermostat
Sherri
basic Honeywell thermostat (slider control - no setback)
and I am looking to replace this thermostat with one that
will keep the furnace out of stage-2 as much as possible.
Currently, it stays in stage-1 for about 15 minutes and
then goes into stage-2 for an hour or so. This is contrary
to the literature which says that it should stay in stage-1
most of the time. I live in Minnesota, so our temperatures
are cold, but usually not extremely cold.
I was told part of the problem is that I'm using a non-digital
thermostat, which has wider temperature swings (up to 4 degrees)
than digitals.
The HVAC dealer suggested the Honeywell T8600 single-stage
setback thermostat, but said not to use the setback feature
on heating mode. They said it defeats the purpose of a
2-stage furnace.
My problem with getting a single-stage thermostat is that it
will still be limited to the 15 minute stage-1 limit. Is
this 15 minute limit adjustable at all?
Then would a better option be a 2-stage thermostat? If so,
does anyone have any brand/model recommendations?
Could there be anything else wrong with the furnace that would
cause such high stage-2 times? Either sizing or wiring?
Sherri
Sherri
I should mention that we have 2 Venmar Heat Exchangers
(one Solo and one Duo), which we run on low all the time,
so we may be losing more heat than normal.
And we keep the furnace fan on low at all times, but my
husband reset the furnace fan speed to the lowest possible
setting. I'm wondering if this would lower the stage-1
speed, if they are the same setting.
My husband is an electrical engineer so he can install
a thermostat if we could find an HVAC dealer who would
sell us one. So far I've had no luck. One dealer quoted
us $500-600 to install a Carrier Thermidistat 2-stage
thermostat. That price sounds outrageous to me. Is that
the average cost (installed) for a 2-stage thermostat?
Sherri
Sherri
air exchangers which we run on low all the time,
so we are probably losing more heat than normal.
And we run the furnace fan on low all the time to
keep the house a uniform temperature. But my husband
reset the fan speed to the lowest setting possible.
I'm wondering if this setting also controls the
stage-1 fan speed. If it it, perhaps it's too low
a setting.
My husband is an electrical engineer, so he will
install a new thermostat if we can find an HVAC
contractor to sell us one. So far I've had no
luck - they claim Warranty issues prohibit them
from selling them to us directly.
And what is the going price for 2-stage thermostats?
I had one company quote me $500-600 to install a
Carrier Thermidistat thermostat. Can that be for
real? That price seems outrageously high to me.
Sherri
John Mills
>
> I have a Carrier 58MVP furnace (1 1/2 yrs old) with a very
> basic Honeywell thermostat (slider control - no setback)
> and I am looking to replace this thermostat with one that
> will keep the furnace out of stage-2 as much as possible.
>
nice models starting rather low in price going up to the high end. Not
sure if the Thermidistat is a 2 stage. A good, reliable model is
White-Rogers 1F81-51. As for price, depends upon house wiring. A 2 stage
stat needs at least 5, some need 6 wires between the stat & furnace. If
you don't have that, it may be hard to pull if you have a finished
basement ceiling.
--
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Jade Falcon One
your husband.
Fan:
There are alot of different models, but most are very similar in design.
High fire/high fan/ low fire/low fan is pretty much the norm. In addition
some furnaces have a
continuous fan speed tap or third fan speed. This is usually set to a very
low setting and is controlled via the thermostat's fan on setting in a no
demand state. On a call
for heat (or a/c) the speed will shift to heating speed (or a/c speed) and
resume low at end of cycle.
Thermostat:
Most multistage furnaces can fire by thermostat, or by time. Yours sounds
like it is set for time. It may be adjustable, again consult the diagram and
installation instructions. If fuel economy is expected by changing the
thermostat, don't expect a huge difference. Depending on the heat loss of
the structure, it may not be able to carry the house in low fire
exclusively. White Rogers IF95 or
IF97 series would be a good choice, although I'm not a big White Rogers fan.
They are designed to keep stage two operation at a minimum by using
intelligent recovery. But again, if heat loss is great, you will be running
on stage two and may actually create problems trying to avoid using it.
In my own home I stage my boiler (multifire) with an indoor/outdoor reset
ratio controller. This is the preffered method to stage as it matches the
output of the unit in proportion to the actual outdoor temperature and
supply temp of the boiler itself. Not only does it control the staging, but
actually modulates the boiler temperature
to match the homes heat loss at a given temperature. Example, on a 50 day,
my boiler temp is maybe 110, but when it gets down to 0 it's up to 200 or
more. I've calculated a savings in the 35% range. There are controllers that
will operate a furnace in the same manner.
You could simply "lock out" the second stage during mild weather via an
outdoor thermostat, and have it engage at a predetermined temperature the
same way that balance points are calculated when sizing a heat pump.
Hope this was helpful....
"Sherri" <le...@kafka.network.com> wrote in message
news:93fi6o$s57$2...@news1.network.com...
Iove doII
suppose he purchased his degree from home depot did he? Of course not. Now
think about the ac company who has to continously train and upgrade their
technicans, be licensed, certified, bonded, insured etc etc etc. Who do you
think should pay carrier for the engineering they did to bring their
"thermidistat" to the market place. the contractor? Do you seriously think
carrier is going to re-imburse the contractor who has to warranty his labor on
defective components carrier manufactures?
At $500, you're getting a bargain. I charge (and get) $750. I've gotten as
high as $1500.00 for a thermostat built by carrier. ( MST16E )
>Subject: Carrier 58MVP/stage-2 firing/thermostat
>From: "Sherri" le...@kafka.network.com
>Date: 1/9/01 9:31 AM Pacific Standard Time
>Message-id: <93fhtc$s57$1...@news1.network.com>
Sherri
So I've got it narrowed down to the following:
Honeywell T8624
Carrier Thermidistat
Carrier Setback Thermostat
Does anyone know if the Honeywell 2-stage will
work as well as the Carrier?
And does anyone know what the difference is
between the 2 Carrier thermostats? It looks
like the Thermidistat has humidity control,
but I was wondering if there are any other
differences.
Sherri
Iove doII
>Message-id: <93i267$dqq$1...@news1.network.com>
The ac contractor you buy them from will probably know the differences. My
recomendation is forget the carrier t-stats as choices and go with either the
honeywell or the white rogers like the previous gentleman suggested
Aaron
it goes into the 1st stage for 16 Mins. if it does not reach set point it
goes into the second stage until set point is reached. You can bypass the
logic by flipping a dip switch (in manual) and installing a two stage
T-stat, any will do. You will get the same operation, the 1st stage first
and if the furnace can't bring the temp up it will go into the second stage
of heat. You may find it goes faster into the 2nd or slower into the 2nd
stage. This is a very quite furnace and you should not be bothered with it
going into the 2nd stage. We have had a cold winter this winter, also in
MN.
I do not understand your concern for going into the second stage of heat.
Check your heat anticipator on your thermostat. You may want to go to a
good electonic t-stat (One stage) so that it will kick the furnace on with
out a drastic drop in temp, allowing it to reach set point on the 1st stage,
and maintain a constant temp. I would stay with a one stage t stat and let
the logic in the board take care of it. You can still set the furnace back
at night to save a bit. The furnace will have to run on the 2nd stage to
bring it up to temp.
Not sure I would be messing with fan speeds with out checking temp rise...
It is always good to wait until the furnace is out of warranty before H/O's
change settings :> Also if you get a elec thermostat make sure you set it
for a condensing furnace 3 cph.
MxIxKxEx99
the speed unless you reset the board to a diff tonnage size.- if you husband
did this he thru the system out of wack,and it will funtion improperly <eg:
running on high fire longer than needed> consult a carrier pro to set up your
furnace properly.
Mike Molnar
14 Years in Service and Installation. :)
"and my mother told me not to make a habit of it" UHOH :Ş
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