Condo I am renting. Central AC and heat. Other folks here have mentioned having heat pump systems that don’t work worth a darn. Lower eastern NY.
Air handler has an electric coil installed. Thermostat has “Heat” and “E Heat” settings in addittion to all the rest.
“Heat” brings on the compressor outdoors and the amount of heat coming through the vents seems piddly. Mind you, we are getting into the 50’s and even 40s at nite here in this wonderful wacky summer we have been having.
“E Heat” brings the heat in and temp up quickly.
Somehow I can’t imagine that running that compressor can be more effi$ient than heating the coil. And I don’t even have a clue how the system works or if it is a ‘heat pump’ system.
Help!
“When the spirits are low, when the day appears dark, when work becomes monotonous, when hope hardly seems worth having, just mount a bicycle and go out for a spin down the road, without thought on anything but the ride you are taking.” — Sherlock Holmes, 1896
Replies
"Somehow I can't imagine that running that compressor can be more effi$ient than heating the coil"
That$ a mi$take you don't want to make.$$$
running E heat setting is about 3X more $$ than the HP at 50F, only meant for when it is in the teens or below outside.
Since it is a rental, and amount of heat coming through the vents seems piddly, it is likely that the system has a leak someplace and low on freon.
Easy way for layman to check is see if the big pipe going into the compressor is cold, if not, the system needs servicing.. The landlord will probably tell you to just run the E-heat, not his $$, and HVAC service call likely in $400-$500 range if a few lbs of freon need to be added.
Serviced this year, blew plenty cold in August.
Piddly compared to the e heat maybe. I'll give it a chance.
Thanks
"When the spirits are low, when the day appears dark, when work becomes monotonous, when hope hardly seems worth having, just mount a bicycle and go out for a spin down the road, without thought on anything but the ride you are taking." — Sherlock Holmes, 1896
don't expect the HP side of the heat to work like a trad furnace. Let it sit at a thermostat setting and see what you get for comfort. The goal is the keep the thermostat setting and not boil water at the vents. Let the compressor do it's thing.
HPs work great here in GA, not so sure about NY.
The heat pump is more efficient. Emergency Heat is for when the temps dip below the heat pump's effective operating temperature (around 30 degrees, probably), or when you need to warm the place up real fast.
Once you get to the temperature you want, set the thermostat and leave it -- don't turn it up and down. This will produce the most efficient operation -- roughly 3x cheaper than E Heat. (What's happening is that the heat pump is literally "pumping" heat from outside into the house, like running an AC in reverse -- you're getting "free" heat.)
The output temperature of a typical heat pump is fairly low -- just lukewarm. So you need to let it run to get the heat -- you can't warm up the house in 15 minutes with a heat pump.
With little to know knowledge of the system, that's what I was thinking.
Us conservatives ain't so dumb............least we know who to ask for the answers (;~)
"When the spirits are low, when the day appears dark, when work becomes monotonous, when hope hardly seems worth having, just mount a bicycle and go out for a spin down the road, without thought on anything but the ride you are taking." — Sherlock Holmes, 1896
Actually you should never need emergency heat.If you have the right thermostat and the system is setup correctly when the heat pump is not keeping up it brings on AUX heat and possibly a 2nd stage of Aux heat.All the time the heat pump continues working.Some can produce usable heat down to -10. The only difference in EMG is that is locks out the HP..
William the Geezer, the sequel to Billy the Kid - Shoe
Supply temperature for a typical gas fired forced air furnace is around 120* F.
Heat pump, R22, maybe 100*. R410A a bit warmer.
Refrigerant charge is critical for heat pump mode. "Beer can cold" method won't cut it.
Depending on outdoor temperature, you can easily get $3 worth of heat for every $1 you spend on electricity. That ratio gets closer to 1:1 as it gets colder... straight electric is 1:1 all the time. The magic comes from latent heat, or energy absorbed/released due to a change in state (refrigerant changing from liquid to gas in this case).
You need the heat loss and unit performance at 17* and 37* F (<<< #'s from memory here) to figure the thermal balance point, utility costs to figure the economic balance point. The performance numbers are manufacturers specs.
My 3 ton, 2 stage 410A heat pump should be able to heat my home near Chicago, IL down to 25*F. First winter with it... we'll see.
Big help.
Thanks.
"When the spirits are low, when the day appears dark, when work becomes monotonous, when hope hardly seems worth having, just mount a bicycle and go out for a spin down the road, without thought on anything but the ride you are taking." — Sherlock Holmes, 1896
No problem.
The heat pump works, it just takes longer. When I fired mine up, it felt lukewarm, but the rising temperature on the stat told me it was working. The "cold blow" can be a source of complaints.
The long run times plus a standard blower motor in the air handler mean higher costs... that is why the economic balance point needs to be figured out.
The advent of variable speed motors means it can be dirt cheap to move the air, and a properly charged 13+ SEER heat pump delivers efficient heat.
Those inverter mini splits work great for small spaces as long as you don't need heat below 0* F.
17 and 47 is the 2 published data points, as least for my York.Likewise I got a 2 stage seer 18 HP installed the end of July.It is setup with dual fuel modulating furnace. 98% and ECM.When it is running gas it the fan is adjusted so that the discharge temp is constant. On HP it has a Hot Heat Pump option. that keeps the blower on low speed when the HP is in stage 2. That is if all of the pressures and temps allow it.It took me a while to get all of the modes figured out. I have the basics, but haven't figured all of the details, specially the defrost cycle.I had to get the HVAC company owner out to go over some of the options and correct the control wiring.But after correcting the wiring I decided to leave one of the setup mistakes alone. Might change it later if it has some affect that I have not realized.The stat was setup with 2 stages of aux heat. But with the modulating furnace there is only one.And the way that the HP/furnace works is that AUX call goes to the HP and the HP inturns calls on the furnace.So Aux 2 is wired directly to the furnace. So that if something happens to the HP control board so that it is not functioning then, eventually the thermostat will go to aux heat, which will directly call the furnace.Looking at the chart in the thermostat setup manual EMG works the same except it never calls the compressure stages.
.
William the Geezer, the sequel to Billy the Kid - Shoe
Mine is controlled through a Honeywell Vision Pro IAQ.
I have 4 stages of heat- 2 heat pump and 2 furnace... but I will probably bypass stage 1 on the furnace.
Using the outdoor sensor, the stat will switch to gas heat at my programmed balance point, and it will do a compressor lockout.
It took a while to get it all set up.
That is what I have.But it is set for the HP to control. I was a little disapointed in that. I had read the manual for the IAQ before I go the HP and assumed that it would control. And I could play with the change over temps.But the HP has an ambinent air sensor in it. Along with a liquid line temp sensor, and an optional discharge line sensor.All of these are used to control the operation of the unit. While I could change it to have the IAQ do the control when you go through the manual it is really clear that whole thing is designed to have the HP do the controlling.And not having the HP do the controlling might mess up the adaptive defrost and the like. It is hard to tell as they don't give that much details.Something else I need to "fix".The furnace ECM has a mode that you reduce the fan speed 15% in cooling to increase dehumidification.And the IAQ has a mode to operate a whole house dehumidifier (and it aslo has a temp depression mode), but the logic of the output is oposite of what the furnace needs. So I am going to need to had a relay.But I also want to drop Honeywell a line and suggest that they felt out a setup option. There is no reason that you could not program that in..
William the Geezer, the sequel to Billy the Kid - Shoe
I guess some of your specific control problems is what happens as equipment gets complicated. My HP is a 16 SEER and nothing really special otherwise.
I have the IAQ set up as a dehumidifier control using the AC unit, and it won't do any dehumidification if the room temp is more than 3* cooler than the setpoint. It has worked well.
I do not have a separate dehumidifier, so I have not looked into the control sequence for that.
The 2 stage AC unit has been a good match for comfort and run times, but it seems to cost more to run than the single stage unit that was there previously.
The ECM motor on the furnace is great.
Let's back up, look at the basics, and maybe clear up some misconceptions about heat pumps.
Everything has a limited capacity. A 1-gallon bucket holds one gallon, and a 1-ton jack will lift one ton. No one would be surprised if either failed to do more than it was described as being capable of.
All an air conditioner can do is move heat from one side to the other. If you make it so that either side can be the 'cold' side, you have a heat pump. All you do is change the direction, which side is 'in' and which is 'out.'
That air conditioner is of limited capacity. For example, it may have a maximum capacity of cooling your house 20 degrre; that is, on a 100-degree day, it can cool your house to 80.
Reverse it, and the same is true; it can only warm your house that same 20 degrees. Maybe that's fine, when it turns a 50 degree night into 70 degree sleeping; but if it gets colder, the unit won't be able to do any more.
That's why heat pumps need supplimental heating elements, of a back-up heating system, in most of the USA.
Now, there are heat pumps that do not rely upon the air outside your home. Instead, they have pipes that go deep into the ground, below the frost line, and have the heat transfer there. Since the earth itself is constantly around 60 degrees, these units can function effectively in winter - simply because they never see the winter air.