I need some advice please.
I recently had a Carrier Heat Pump installed. The air conditioner works
perfect. Now we are into fall and I noticed that even though the
temps are still above 47 degrees, my auxiliary heat would come on. Most
of the time, it would stay on for three minutes, then go off. It is my
understanding it should not come on until it is below 35 degrees.
The Carrier tech came out and locked it out at 35 degrees, so I should
be OK now. I wasn't aware that this could be done.
He asked me if I wanted to have the Auxiliary Heat indicator turned off
on the thermostat. I said sure. Now, I am wondering if I did the right
thing. If it is still not working properly I have no way of knowing.
What would you do? Have the man come back and adjust it so the aux
light indicator comes back on, or just leave it? I would do it myself,
but I believe he disconnected a wire at the back of the thermostat, and
I don't feel comfortable messing with the electrical wires.
On Saturday, November 9, 2013 6:19:40 AM UTC-5, philo wrote:
You have to wonder about the competence of an installer
that would put in a new heatpump system where it puts
on auxillary heat when it's 47 outside. And maybe the
design of a system or thermostat where it puts it on for
3 minutes at all. What does it figure out in 3 minutes that
it didn't know to begin with? Maybe that it is generating
sufficient heat from just the pump. But it should be able
to figure that out with just a temp sensor on the outside
Whether she can figure out where the wire goes and do it
herself, IDK. If it's a commonly available thermostat, there
should be install instructions on the web. However if it's
a Carrier one that's only dealer installed, etc, may not be
able to find it.
I would definitely want the indicator on. Can't imagine
why she told him to take it off. That he wanted to take
it off is yet another sign to me that I wouldn't want this
guy installing anything for me.
If you're going to own a house, you should learn to be comfortable
with low voltage wires. if it's a new thermostat, you have the
instructions for it, right?
I think the thermostat uses 14 volts but even if it's 20, you can't
hurt yourself with that even if you held the wires in your wet hands.
Even if you put them all in your mouth (though I'm not recommending
that.) You'd get a tingle and your tongue would jerk back, but even
if you could force your tongue to stay there, I don' tthink you could
hurt anything. (I don't force my tongue to stay on even low votlage
electric wirees.) Just write down what color wire went to what
number screw before you disconnect anything (you shouldnb't have to
disconnect anything, unless it's just one wire that goes somewhere
else. More likely there will be an unconnected wire you have to
connect. Also learn to make drawings, of all the screws with what
color wire goes to each. Drawings are very important. It's easy to
forget without them.
Do the instructions say which wire goes to the light indicator? If
not call the guy and ask him and tell him you a) didn't have enough
time to give a good answer (if you want to sort of blame him) or b)
you made a mistake when you told him to disconnect the light (maybe a
better approach since people like humility) And you'd be happy to
connect it yourself if he'd tell you which wire and which screw. If
he says he will do it, ask the charge. He may say free, esp. if he is
near your house at times. If he wants more than you want to pay, say
you canb't allocate more money to this, and maybe he'll do it for free
or at least he'll answer your question.
Might want to do some research before encouraging others
to start working on their own wiring. I installed furnaces
for six years, and all the low voltage thermostats I did
were nominal 24 VAC, and often you'd see 26 or 27 on a VOM.
Since you don't know the typical low voltage for stats, do
you REALLY think you should tell people to work on them....
On Sat, 09 Nov 2013 07:28:47 -0500, Stormin Mormon
You're going to get hurt on 26-27V? It's pretty easy and safe if
YOU'RE SURE IT'S A LO VOLTAGE SYSTEM. Some aren't (though a heat
pump's thermostat should be).
The bigger danger is shorting the 24V supply and blowing a fuse in the
air handler, or worse. BTDT. Just follow the instructions and it's
not difficult or dangerous.
yes if you decide to wire it yourself, turn off the power to protect the eq
also, no one mentioned that most heat pump systems use a 2 stage thermostat
. If the room is only a little cooler then the set point, the heat pump co
mes on for stage 1. But if the room is more then 2 or 3 deg cooler than th
e set point, like when you first turn up the heat, then stage 2 will come o
n (the aux heat will come on). This is normal. Think of it a 2 thermostat
s, stage 1 is set for the setting you see, and stage 2 is set a few degrees
below that. Once you understand that, if you want to keep the aux stage 2
heat from coming on, you make smaller increases in the setting. If you ma
ke a big increase in the setting, the aux heat will come on and that is no
When it is below about 32 outside and damp, I turn off the heat pump to avo
id the defrost business, but I have oil for the aux heat so its not so expe
On Sunday, November 10, 2013 10:45:45 AM UTC-5, Ralph Mowery wrote:
agreed, and that is what I said except at 32 instead of 25. Below 32 if you account for the inefficiency of the defrosting and the wear and tear on the compressor and the discomfort of being cold in the house, it starts to pay to burn some oil.
I'd like to see someone develop a solar assisted heat pump. Use some solar heat to get the air up to 32 so the heat pump can work well.
On 11/10/13 11:12 PM, email@example.com wrote:
By "ground source", you mean geothermal, is that correct?
Is there a temperature range below which geothermal needs an
"auxilliary assist" (i.e., electrical heat strips) as well?
I thinking of an area like Pennsylvania, where temps can
drop down close to 0 at least a few days of winter.
I see plenty of homes with "regular" (non-geothermal) heat
pumps installed around north/north central PA. When shopping
for a home that has a non-geothermal heat pump installed, at
what seasonal temps does it become impractical or
On Monday, November 11, 2013 5:38:31 PM UTC-5, John Albert wrote:
My understanding is that geothermal systems are sized so they
are all that is required. They're expensive enought without
having the added complications of a hybrid system. That is the
big drawback, the huge initial expense compared to other
That depends on a lot of factors. One big one is the
COP of the unit. Is it a 15 year old one or a newer, high
efficiency one? How well insulated is the house? I think
in most cases the problem isn't that it's not economic
to run the heat pump. They have decent COP's down into
the teens. The problem is that even though you're still
getting heat produced at a reasonable cost, you just can't
get enough heat to supply what the house needs, unless
the house is exceptionally designed to need less heating than a
typical home. I think for a typical house, with a relatively
new higher eff heat pump, that point probably occurs in the
20s, to maybe teens,depending on how efficient it is,
how it's sized, etc.
No, though some people may call it that. Geothermal is passive.
The outside air temperature doesn't matter at all. If the ground gets
cold enough to require such, then the ground "source" isn't big
My brother had an air-source (the alternative to ground-source) heat
pump in N. Philly. Around freezing efficiency falls off rapidly. At
some point, probably above 20F, they stop working entirely without
On Monday, November 11, 2013 8:04:14 PM UTC-5, firstname.lastname@example.org wrote:
At the risk of setting off another profanity laced response, why
don't you answer the question and explain what exactly you meant?
AFAIK, ground sourced heat pump for a house typically translates
into geothermal. So, if it's not that, then what is "ground sourced",
in this context?
It does matter to the extent that the geothermal system has to be
large enough to deliver the heat needed at the lowest outside
temps the house will experience.
I don't believe that's true. The curves I've seen, for modern high
efficiency heat pumps, COP falls off gradually through a wide operating
range. There isn't a sudden acceleration in loss of performance below 32F. COP might go down by 15% from 30 to 20. The problem is that while the
performance is gradually decreasing, the need for more heat is also
On Tue, 12 Nov 2013 07:34:04 -0800 (PST), " email@example.com"
I did, dumb ass. I can't help the fact that you're illiterate,
The heat is actively pulled from the ground (heat pumped from the
ground), rather than passively (heat passively removed from the hotter
ground). There *IS* a difference.
Not just the lowest outside temps, but the integral of the (delta)
temperature over time. You are actively cooling the ground. That
can't be done forever, unless you've tapped into an infinite heat
sump, like a "river". If the heat source is too small, eventually you
will cool the ground enough that the heat pump has no heat to pump.
Unlike an air-source heat pump, this happens over a much longer time
(over a heating "season").
On Tuesday, November 12, 2013 5:25:40 PM UTC-5, firstname.lastname@example.org wrote:
And there you have it demonstrated again folks.
KRW is incapable of answering any questions civily.
Again, you posted:
" Instead of wasting money on a solar assisted heat pump (daytime is not
when you need the heat) why not do something useful and buy a
ground-source heat pump?"
To which JA replied:
"By "ground source", you mean geothermal, is that correct?
And then you say:
"No, though some people may call it that. Geothermal is passive."
Some people? AFAIK, virtually everyone refers to a ground
based heat pump system as one form of geothermal including experts
in the field, eqpt manufacturers, companies installing it, govts,
etc. Google and you will see. So, what are you talking
Around freezing efficiency falls off rapidly. At
As usual, no facts, just curt replies that don't address anything.
Typical, when you know you're wrong, yet again. If you have COP data
from a typical modern residential heat pump system that shows the efficiency falling off rapidly below 32F, I'm sure we'd all like to see it.
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