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What is your location?

It appears you have a 3 1/2 ton Heat pump condenser.

You need to find out exactly the size of your heat strip. Every 5 K of heat strip yields about 17 KBTUs of straight emergency heat, the most expensive type of electric heat, normally used for backup and emergency heat.

Yes, i would say you are undersized on your outside condenser.

BTW, Payne brand is a low end POJ. Sorry but true.

You need to have a load calculation performed for correct sizing.This is something you can do yourself for a nominal fee if interested.

Sounds like you have a zoned system but you should have some type of zoning control since you have separate thermostats for upstairs and downstairs.

IMO

Thanks, I live in Indiana. Since I am ignorant with this topic I figured it would be better for you guys in the know to fire some questions my way. I am aware from reading the Payne is not the highest quality system. That is part of the reason I thought that the person who built the house skimped. The person had the house built and within a year it was in foreclosure.
Last year we had a very brutal winter and my electric bills were pretty close to people with a similar size house, a little higher but not double or anything.
If there is only one hit strip and it is too small is it possible to add one or two more, or does that depend on the furnace itself. My friend I spoke with last year said we could just add some. My best friend is an electrician so if I needed to upgrade wiring to the unit itself that should not be a huge issue.
The upstairs of my house has two bedrooms on each end of the house and the entire middle area is one large open room. That room itself is close to 1000 square feet.
Another thing I noticed last year is that the heat pump will run the defrost cycle and the furnace unit will continue to run and circulate air. When this happens it feels to me like the air coming in is cold. Should the unit defrost while everything else is off or is this normal. If not is there a way to change that from happening?

Defrosting has the unit essentially switch to cooling mode so the outside coil heats up (as it does in the summer) to melt off the accumulated frost. The heat strips activate to counteract (reheat) the cold air that would otherwise be blowing inside the house (air conditioning). If it does blow cold air (cooler than during heating) then the strip(s) aren't of sufficient capacity to counteract or balance the cooling.

When temps drop below 30F,why don't you just set the tstat to aux/emerg heat? That would stop air movment and save expense of running indoor blower and outdoor pump between strip cycles.

klem

I tried that last year and here is why I don't do it anymore. I had two HVAC guys tell me that my outside unit was "wasting money" if it was running when temps get below freezing. I let it run and one night we had temps at 20 below zero with wind chill temps close to 50 below zero. I know this is torture on any heat system but taking their advice I set me stats at 65 degrees and put it into emergency heat. The furnace ran all night and when I woke up the temp in my house was 58 degrees. I called a friend of mine and he told me that likely one of the breakers had tripped on my strips or one of them was out. That is when I realized I only had one breaker, he told me I should have more based on house size. He then told me that shutting down the heat pump unit is not necessary for newer units. He told me that 15 years ago this was the case but he said the newer units can make some BTU's at temps below zero. I switched the unit out of emergency heat and within an hour or two my temps climbed back up to 65 degrees. This confirmed to me that my heat pump was still helping even during the bitter cold. He told me the only time I ever want to manually shut off the heat pump portion is if it starts having mechanical problems. Some people still say heat pumps aren't good below 20-30 degrees but many people say this is old school and does not apply to todays units.
Possibly if my heat strips are lacking then it would be better to put it into emergency heat but my past experience was that the strips alone could not keep up and even with bitter cold temps the heat pump still helped the entire system.
I am still curious on people thoughts on what is the highest number of BTU's/strips that my furnace could contain with a single 60 amp breaker. And also a guess as to how many square feet in Indiana that unit should be able to heat?

With only a single 60 amp breaker, you have 10 kW of emergency heat, a little over 34,000 BTU, 2.7 tons.

With that many square feet I don't know how you could not be undersized on strips and condenser. Do you have a 200 amp service? For now you could have another set of strips added and stage them so that you only run two as little as possible. Even adding an extra 10kw would make a world of difference. I would look into upgrading the whole system when the weather moderates.

Thanks for the info. I will look into adding more strips. I just wanted to get some good info and get a grasp on my options so when someone comes out I will know if they are feeding me a line of crap or not.
I am guessing that by adding strips it should help with my heat bills, even though I will cost more when they are running it won't be running near as much, is that a safe assumption?

You should lay some groundwork on a new correctly sized good system. I don't like the idea of adding additional heat strip capacity to overcome an undersized system. Keep in mind, it will be undersized not just for heating but also cooling.

IMO

Do you access to natural gas?

No natural gas. The cooling seems to do just fine. The highest electric bill I had last summer was around $150.00, which I don't think is bad for a house this size with a wife and two kids.
Before I started this thread I felt more like the heat strip portion of the unit was undersized but the rest of the system was OK. Sounds like that is not the case.
Since my electric bills are not super high (compared to others in the area) would it be financially wise to think about replacing the entire system now? I just can't see the monthly savings being big enough to replace everything because it is undersized. Again I don't know much about this so that is why I am asking.

Another question.

Is there normally a time limit that the unit will run before it kicks into emergency heat? I had he stat set at 65 and when my wife got home she kicked it up to 69. It kicked into emergency heat and the house heated up as it should. Since then the unit has been running non stop (not in emergency heat) basically blowing room temp air just to maintain. It has probably been close to three hours it has ran that way. Im not sure if there is a way to adjust this or not. I thought when I had one of the thermostats replaced it stated that if the temp dropped more then two degrees it would go into emergency heat.

Re: Another question.

"I had he stat set at 65 and when my wife got home she kicked it up to 69"

I can tell you for a fact that heat pumps work best when you leave the thermostat setting alone. We have lived in this house for almost 30 years and I have spent 29 of them trying to get my wife to stop "helping" the heat pump by turning it up and down. This year, we have the same setting for the past three months and the house is far more comfortable and economical.

Remember, when you go from 65 to 69, not only must the heat pump raise the temp of the air inside the house, but must raise the temp of the contents of the house - furniture, walls, etc. It doesn't make sense to let those items cool off during the day when the heat pump may be able to produce more BTUs for the buck and make the heat pump raise the temp when you get home when the outside air cools off.

The three hour continuous run could be a direct result of the heat pump trying to raise the temp of the house contents at a time when it produces less BTUs.

Depending on the outside temp and your insulation, and the fact that your heat pump is marginal for the square footage, it may be perfectly reasonable that it runs continuously to maintain 69. Most older heat pump thermostats work on the simple principle that if the temp falls below two degrees below the setting, it activates the Aux heat. Newer thermostats may have a more sophisticated pattern.

Thanks for the advice. Most things I have read says it is more economical to drop temps some. The reason I usually do is nobody is at our house during the day (like most places) and my wife goes to be early along with the kids. So it stays on 65 probably 18 -20 hours of the day then when the kids and wife get home at 4 she kicks it up until she goes to bead around 8 then it gets dropped back again. I have never been able to test which way works best because it seems like each month here in Indiana is so different from the previous month.

Heat pumps are poor on recovery depending on many factors such as current heating load to outside temp and sizing of system. You will definitely go on heat strips in recovery unless there is outdoor sensor and lockout.

Saving any money?, marginal at best.

IMO

In most parts of the country the heat pump has to be sized for the cooling load. This is necessary so in cooling mode the equipment does not short cycle. Long cooling cycles help reduce humidity and in the long run will help the equipment last longer and run more efficiently. Unfortunately this sizing method causes the heat pump to be undersized for the heating load in colder climates like yours. This is why you need enough heat strips to provide enough heat on very cold days. You need additional heat strips and they should be staged.

You should also invest in a better thermostat so that if you do a set back of more than two degrees the heat strips will not automatically turn on. The thermostat needs to be connected to an outside sensor so it can monitor the outdoor temperature and make a decision when the heat strips should be used and in what quantity.

There is a lot of debate if using temperature set backs with heat pumps results in saving money. I would think that if you set back the temperature four degrees for 18-20 hours that there would be some energy savings. But most of the savings will be lost if the heat strips turn on for every set back recovery. This is why your first priority is to get a better thermostat.

We've been using a heat pump in Indiana for 13 years and have both comfort and efficiency. 13 SEER, 8.5 HSPF. Carrier mid-grade model. Here are some tips.

Find out if your thermostat has hidden settings by getting the install manual. Ours is called "Installation, Start-up, and Operating Instructions." On our system, there are up to 17 options that can be adjusted or changed on the hidden menu, depending on what equipment you have. Granted, without the outdoor sensor, many of the better and/or energy savings adjustments can't be made. Can a outdoor sensor and/or new thermostat be added to your system? That shouldn't cost too much.

Electric auxiliary heat should supplement the output of the heat pump, not replace it. Many heat pumps have COPs above 1.0 down to -5 degrees F. In other words, it's cheaper to use the heat pump for any heat it can produce until the COP drops to 1. 10 kW electric strip heat should work as an auxiliary for 3,000 sf, except at maybe the most fridgid temps like last winter. We have 15 kW strips on 2200 sf (1982 home, moderately tight, oversized HVAC system) and it's hardly ever used because I have it locked out to 5 F. Yes, the heat pump works fine down to 5F and then below that the strips come on to assist.

Emergency heat is more correctly defined as locking out the heat pump to strip only heating. This might be used if the heat pump fails, but otherwise there is no need to use it. We've never used the Eheat setting.

Wear and tear from constant compressor use? The system keeps going strong after 14 years. Proper maintenance, of course.

If your system has a "always on" low speed fan setting, use it during the heating season. This is especially important for two story homes in order to prevent air stratification and to circulate the limited heat output. I'm assuming you have returns on both floors?

Don't use big temp. setbacks. Our thermostat has four programmable time periods. We go with 66 night, 67 wake, 68 day, and 70 evening. The actual temps. are not so important, but the wake to day time change is only one hour, 5 AM to 6 AM. This gives the heat pump time to gradually increase the temperature in the cold early morning, which is sort of the goal with a limited output heat source. Hope this helps.

Our highest electric bill ever was last January at 1,778 kWh total use and 1,328 kWh for the heating portion. I'm guessing the system put out an average 13K-16K BTUs per hour during that cold month, with most of it coming from the heat pump.

OP. Sounds like your heat pump may be a little undersized for heating. It may have been sized for cooling (rather than a cost consideration by the original owner). As such, backup electrical resistance strip heating is included. You can get an additional 5kW or 10kW added to your air handler (may need some electrical work done at the breaker to support this). Less efficient than a correctly sized heat pump but probably a lot cheaper than replacing the whole system. If and when the system finally gives up the ghost, get a detailed heat gain/loss done and be sure that the installer recommends an appropriately-sized system.

That is true tiger. I didn't think about the total undersized system just the heat strips. He needs proper airflow and properly set up ductwork to utilize the bigger strips. Multiple quotes and give the info to the members here to give you advice.