Howdy along with my new house comes a new device to me. A heat pump. When I moved in I had an inspection done, it was Aug so they could test the cooling but not the heating part of it. Now that Santa has breathed a solid mass of cold air down across the US it is time the heating part of it should come into work. I am in San Antonio and my wife is home, she turned it on yesterday morning to heat up the house because it was cold. She called me two hours later saying it has only warmed up three degrees and the fan has been running the entire time. Looking on the internet it says I can turn up my back up heat source (electric in this case) to come on earlier to help heat up the house faster. I guess my question is: How fast should it warm a 3000SQft house up 15 degrees? Also I would like a T-stat that will bring the temp down at night and up in the morning like I had on my gas furnace. Is it a good idea to do it on a heat pump? I just plain need help understanding heat pumps. Thanks Mike
We have had heat pumps for the last 15-20 years. They work very well but I can't help yo with trying to bring the temp. up 15 degrees. Ours has setting for wake, home, evening and sleep in three zones. We set the temperature to what we want for that time and let it do it's thing. It does have a setting for auto but I haven't used it but I think if it's set it will decide if you need heat, cool or nothing. I don't know what it would do if one zone was calling for heat an another for cooling.
In my opinion you should not be asking a Heat pump to bring up the temp 15°very often. I set my heat pump to 69° 24/7 and let it run. Often gas furnaces are 5 time bigger than they need to be with almost no affect on the fuel usage and comfort so they can quickly change the temp. A heat pump is an air conditioner and AC does not work correctly when over sized.
The way to tell if the heat pump is working is to measure the air temp in supply and return ducts and calculate the difference you should get a number close to 20°.
You may get lucky and find someone replaced the thermostat with the wrong model or miss wired. If it worked Ok in AC mode the reversing valve could be stuck.
I say turn on the electric heat yes it will cost 2-3 times as much as a working HP.
Hard to say. I'm sure a heat pump installed in Texas isn't tuned to high heating requirements. Should be some specs online for the system. You should get some kind of idea based on the breaker size. It takes one hell of a toaster to bring 3,000 square feet up 15 degrees! Lots of Google help out there. One article mentions not using a setback thermostat when the recovery must be done with the backup resistance strips. Too expensive to recover the temp
First of all, like others have said, asking a heat pump to increase the temp 15 degrees in any timely fashion is wishful thinking. I don't know how your thermostat and system are set up but on mine the backup or "emergency" heat (electric strip) comes on whenever the thermostat is moved 3 or more degrees higher than the current setting. It stays on until it reaches temperature and then the heat pump takes it from there.
I have a maintenance contract on our two units. They are tuned up each Spring and Fall. This way I know they are ready to go for summer and winter demands.
Your heat pump will put out air at about 80 degrees. A gas furnace will put out air that is over 100 degrees. It will take your heat pump a lot longer to bring the temperature up than a gas furnace. Even so, it is capable of keeping your house at the set temperature if it is working properly. Most manufacturers do not recommend setting back the temperature more than a degree or two at night or when you are away unless the away time is 8 hours or more. Running the back up heat should be an emergency plan not a quick heat change. It will cost 2-3 times more to run the back up heat than running the heat pump.
I live in Northwestern, PA and we've heated our 2000+ sqft house for over 35 years with a geothermal heat pump system. It keeps our house within 1 degree of the set point and our total electric bill is less than $2400 per year. We have no gas nor alternate heat source.
I have a Honeywell RTH9585WF1004/W WiFi digital thermostat that runs both the heat system (3 stage) and cooling system (2 stage) that works very well. It allows me to monitor and adjust the settings and temperature from my smart phone.
As to heating 3000SF. quickly don't forget that you are heating much more than air.
A house has a tremendous amount of thermal mass in walls, furniture, floors etc. Specially if you have stone fireplaces and tile floors. These cold surfaces take time to warm up or cool down.
Call a heating pro. He can quickly tell you if your unit is putting out the expected amount of heat.
I have heat pumps in the house and shop here in TN. Today it is 23F outside. The inside is a comfortable 75.
A heat pump does not pump out nice warm air but air with a very slight difference between the inside ambient and the target heat. If you put your hand over the register it might not even feel warm but can be checked with a thermometer or thermocouple. It may take hours to raise the temperature significantly unless you activate the emergency electric strip heating, then the register air will feel warm and the electric meter will show it.
The very small difference between the ambient temperature is what makes the heat pump efficient. I'd give it plenty of time before being concerned.
Also, to check if the heat is working, go outside and feel or measure the air blowing from the outside unit. It should be colder than the ambient outside temperature.
If in doubt, any heat pump service can quickly check the unit. I do it myself with two thermometers, or actually, a dual input thermocouple reader. The difference in temperature will be very small.
I have been reading on them and how they work, so I have a better understanding of how they work now. We where in the habit of just turning off the heater when the temps outside didn't require it. We will have to rethink that idea.
I think if we had turned it on when the weather was still nice outside we would not have had the heat up issue. I am not at home to see what T-stat we have installed I do know it matches the Trane system and was installed at the same time.
My wife never said the emergency heat strip kicked in which makes me wonder if it is working or?
I will contact Trane the installer to get a WiFI T-stat so I can see what is happen.
As a Home Inspector I checked thousands of heat pumps over my 30+ year career. A couple of simple things anyone can do. Check the air temperature at a supply and return when the system has been running for a few minutes. You should get a 12 to 20 degree rise. If you get less than 12 it's likely the refrigerant is low. If you get more than 20 it's likely the air flow is restricted. That's if the heat pump is running without the backup or emergency heat. If the emergency heat is running it's likely the differential will be much greater, maybe 30 or 40 degrees or more.
With electric backup the units often will run in a combined mode, with both on at the same time.
Your system will likely ice up the outside unit from time to time and have to defrost. It will momentarily reverse and run as an air conditioner, heating the outside coil, and run the emergency heat to prevent cooling the house. It make make a noise like a sudden release of air, then the fan comes on and there's a cloud of mist. I had people observe this for the first time and thought it had blown up.
Another thing you can do is feel of the tubing at the outside unit. This is the two copper pipes that run between the two parts of the system, one about 3/8" and the other about 3/4". When running, one should be significantly warmer that the other. the large pipe should be nearly hot enough to make you take your hand away. (In AC season the larger pipe will be cold, probably sweating.)
Keep in mind that a heat pump is an air conditioner that runs frontwards and backwards. In summer it cools the house and dumps the heat outdoors. In winter it cools the outdoors and dumps the heat in the house. It does not create heat, it just moves it back and forth. It's much cheaper to operate than the electric backup.
It's probably not a good idea to use set back thermostats for a heat pump. (Maybe, but maybe not so much). The stat would be allowing the house to cool down over night and then asking for heat early in the morning when the outside conditions are at there worst for a heat pump. If the outside air is above about 47 degrees the heat pump is three times as efficient as a electric furnace. At 32 it's about double and at about 16 it's even. No point in running the heat pump below about 16 or 20 degrees outdoors. Some systems have a "set Point" built in and Won't run as a heat pump when it's too cold. If you do use a set back stat, make sure it's one designed for a heat pump. It makes a calculation as to how long it will take to raise the temp and turns on far enough in advance to allow the heat pump to bring the temp up slowly without bringing on the expensive electric backup.
I saw thousands of programmable stats. Essentially every one of them was set to "Hold 72". I talked to people that told me they got tired of playing with the stat and gave up and just used it as a regular old dumb stat.
In winter, every degree you turn the stat down may save you 3% on your bill. Might be better to run yours down one degree and get used to the cooler house and save that way. Remember, Mr Rogers always put his sweater on.
3000 SF is pretty large for a single heat pump. Locally, houses that large often have two.
A great early stocking stuffer would be to go buy your wife a nice base layer of thermal underwear. Patagonia is great but expensive, Under Armour is also good, and I have both, but the last time I was in Academe Sports I noticed they had their brand Magellan out that looked better than what they once offered so I got a set. I have worn them a couple of times, and will give them high marks for a much better price than the others. Oh and don't forget some good warm socks.
I guess we need to change our ways of shutting off the heat and AC when the temps are nice, or just remember to turn it on while the temps are still nice before they go to being not so nice.
1. A modern unit is much more capable than one 20 years old. Any advice or experience offered needs to be in the context of how capable the unit is for extracting heat from air, and the capability of the controller. Our upstairs unit is 26 years old and our downstairs unit 3 as we replaced it preemptively with a more efficient unit.
2. Unlike others that have responded, we actively manage out heat. The house is cooled at night 10 degrees below daytime "out and about" living conditions. Upstairs is maintained cooler than downstairs. Because we have air ducts that can handle the air flow, unused bedrooms have their air throttled to a trickle. When we are away for a day or more we drop the temperature to 55. If the outside temperature drops below the heat pump break even efficiency we turn it off and use resistance heating to save the heat pump from running 100% of the night. This management is enabled with a capable control unit, which any modern controller will be.
3. The controller is what you and your wife need to learn how to use. It can be programed to do what you want the temperature to do and the heat pump will take care of the commands. If we are going to be away we easily set a temporary temperature to 55 and it holds there until we return. Upon return we hit "run" and the heat pump may or may not kick in resistance heating for a short time to warm up the house air and then the heat pump efficiently kicks in to heat the house itself.
We program the heat for each day. The house cools at night and warms before getting up in the AM. This schedule can be set for each day of the week. You may want the heat to come up later on the weekend if you sleep later on weekends.
Bottom line- you need to own and then have your wife learn how to program a capable controller.
That said, if the controller asked the heat pump to bump the temperature up 15 degrees and the resistance heat did not come on something is not working right.
Also, son in law worked in this area. Some installers don't know enough about what they are doing to properly specify and install what they sell. So you can not assume you have the right equipment or it is installed properly. Also, the compressor can leak refrigerant. When low efficiency is poor. Since the unit is new to you, have it checked.
The break even temperature has gone ever lower over the years. For our 26 year old unit it was about 20 degrees. Our new one is 12 or 14, or 10 depending on what day of the week I asked for technical specifications.
Some of the newest units actively adjust the heat pump and fan for demand and they essentially run continuously. Might squeeze a tiny bit of efficiency out for advertising claims but it seems a stupid idea for equipment wear.
It doesn't seem too much to ask for someone to know how to program a controller when they carry around a "smart phone" that requires orders of magnitude more knowledge to interact with it. Most people are not too stupid to learn to program a controller, but they could be too lazy. If too lazy they will have to work harder to pay for more energy.
We had the house inspected and they stated they could not test the heat side of the heat pump because it was in cool mode. This was in July. We assumed (wrong) that we could use it like our other forced air heaters and just kick it on when we needed. It seems ASSUME did its thing again and bit me.
The house is up to heat now and holding it easily so we are OK for now. I get home on the 22nd for a week and will figure out the best controller to use along with have it inspected by a Trane certified company if they have a T-stat that works with Nexia (my home security system) I will have it installed at the same time, this will make sure I don't mess it up(-;
The Honeywell RTH9585WF1004/W WiFi digital thermostat that controls my system is a modern thermostat and it does an excellent job of controlling our system with very minimal need for adjustment once it is set up. Set up is pretty easy. It automatically controls the heat and cooling stages and even turns the panel display red when the emergency heat is activated for what ever reason. It anticipates temperature setting changes so that it doesn't run the heat pump continuously for programmed setting changes. You can set it for plus/minus 1 degree or two degrees.
It is Wifi enabled so you can monitor and or change settings when you are away from home.
As far as turning the system off when conditions outside moderate, any thermostat will not turn on your system unless the thermostat setting calls for it.
The angst about bumping up the temperature XX degrees is overwrought. We manage this way. The resistance heating will come on and heat the air in the house. It will not stay on until every 2 x4 is up to temperature. There will be 50 other things you can do to "save" the piddly amount of energy "wasted" by managing the way you prefer.
Our rates are not that of CA! Our typical winter electric bill is $150 for 2600 sqft, plus basement that is largely heated by loss through the upper un-insulated floor. Biggest ever bill was $200. Payback for any capital expense to save on a $150 bill will have a long pay back time.
Other than WiFi our 26 year old controller does the same which leads me to guess that any controller is going to have this functionality. One just has to learn to use it. When we installed the new heat pump we kept the old controller because the replacement didn't do anything the old one couldn't do (saving $75).
Spring and Fall the controller is turned off.
The need to diddle with the controller by WiFi escapes me. I can imagine in my mischievous youth I would have spent hours trying to hack a neighbor's heat pump, if I had neighbors, and had a grand time.
security cameras sensors etc. The Honeywell is not compatible with it, Trane and American Standard make one that is, so I will most likely use one of those.
I can program it form the APP on my phone or computer as well as have programmed setups. It will look at the outside temperature and humidity from a sensor I have installed outside and adjust to what it needs to to keep the setting.
Now just to be home long enough to finish off all these small jobs.
"It will look at the outside temperature and humidity from a sensor I have installed outside and adjust to what it needs to to keep the setting. "
Adjust what? We have had a heat pump over 3 generations of this technology and none needed to know the outside humidity to work just fine. That $75 box on the wall will do all that needs to be done if you just learn how to use it.
You are way overthinking what is needed to heat your house efficiently and effectively. Implementing and keeping up with all this unnecessary technology will erode the time available to build stuff in the shop.
but I already have the equipment, also I travel a lot so I am not around most of the time. I have garage doors I can open and close from my system, also all my personnel doors I can lock and unlock. The cameras watch the garage doors so when I get away from home and look at my wife and say did you remember to shut the door we can look and see.
For the T-stat it really just makes me feel better. Nothing more or less
I have been traveling with my wife on a two or three week trip and needed to turn on the heater a few time while on the road, because we used to turn it off when not needed.
I have a learning curve on the way a heat pump works and appreciate all the answers I have been getting.
I believe the geothermal heat pump is the most efficient choice, especially in cold climates like your part of the country. If I were building new today this is what I'd install. The up front cost is absorbed into the overall cost of constructing a new home and doesn't feel like it hurts the budget as much as if choosing one as a replacement to an existing home.
The newer more modern heat pumps are far more efficient than what was installed 20 years ago. With advances in refrigerant and use of variable speed fans and even variable speed compressors, today's heat pump can pull heat from colder outside air and run with greater efficiency. Still, that doesn't compare to the efficiency of geothermal heat pumps.
Just to give you an example we were away on vacation and the house was set for A/C. We had a dog sitter staying in the house and the outside temps fell into the low 40's for a few days. I was able to see the weather change from where I was and change the system from cooling to heat without trying to explain to the dog sitter how to work the thermostat.
