Heat Pumps, opinions please

[oldodge41]

I will ask here because it isn't an hvac forum but I value the honest opinions typically expressed here. I am thinking about having a heat pump installed in my home. Currently oil fired forced air heat and a couple (3) window unit A/C's. Anyone have any experiences, good or bad. with heat pumps. My current oil furnace is 30 years old and it works fine. I have considered keeping it as a backup heat source, but have received mixed opinions on the value/hassle of doing so. I live in Pennsylvania and we have a wide range of temperatures throughout the year. My other option, I guess, is to stay oil heat and add an ac unit as I am trying to get away from window units to cool the entire house. 

[Plymouthy Adams]

Heat pumps are not the best value for primary heat as the effective range of heat transfer is such a small window.  You will be needing aux heat to supplement this in your neck of the woods I assure you.  Mostly this is resistive heat strips.  These are not off the wall in cost, but costly to operate and well, all fuels are expensive these days.  Not sure of availability of natural gas in you neck of the woods as you may well be outside the distribution piping but I prefer the all in one outdoor package where the noise of the fan is gone from the living area associated with the split system installs and the gas fired units are very clean in operation and normally maintenance free. 

 

IF you are rural and can get your aux heat in the manner of a hydronic heat system preferably wood fired and tied in with the all in one unit, this work so amazingly well, at least for me and I heat a modest sized home and can expand to four circulation systems all under individual control.   Big push however to remove these wood fired units from use by certain groups of folks.   

 

You are wise to consider these upgrades when neither the heat or AC in in demand.  I have run my 5 ton AC/heat pump in heat pump mode one time only in 6 years, I tested it when I did the initial install of the package unit.  I did add the need circuits to allow the heater to take command of the indoor fan for circulation when call to heat by the second thermostat.  The AC will still kick on when and if needed say we have a few days of good temps here in the south during winter.  The AC thermostat stays wired active 365/24/7 and will override the heater if it is switched on....but that only has happened maybe twice.   The hydronic unit in heat mode is full automatic in all manner with the exception of putting wood in the firebox, no automatic hopper or auger feed here, got to put logs in manually. 

[kencombs]

I had a dual fuel system install in 1980, long before that became common.  Mine was the only one local installers had experienced.   In '73-74 I did first heat pump and really liked it, but the electric backup/supplemental was expensive on really cold days.  And, heat pumps were not as efficient below freezing as today's are.

 

So, when I built the '80 I did heat pumps with propane aux heat.   NG wasn't available at the time or I would have used it.  Very happy with that set up.

 

In my home today I have a high efficiency mini split in a room I added on.   Works down to zero and very cheap to operate.

 

Depending on the size and design of the home, mini splits can be a good solution.

[oldodge41]

I was thinking I want to stay away from resistive electric heat for a couple reasons. One is cost to operate and second is the ability to backup my heat source electrically with a reasonably sized portable generator in the event of an extended power outage. My oil furnace takes very little electrical power to operate. I am in the shale gas region, but unfortunately not in a NG distribution area. I am rural and if I were building new I would love to have a hydronic heat system, but my home is already ducted for forced air and I think it will be much more cost effective to stay with that. I would probably opt for a coal unit in that case. I absolutely hate cutting wood. LOL! One local contractor is touting a mini-split system with a single zone air handler that would tie right into my existing duct system. They claim it is perfect for our area and climate with no backup heat source necessary for our winters. I believe it is a Mitsubishi branded unit. Salesmen can claim anything, that's why I am asking here for your real world experiences. I will probably consider all the options until I get so confused I just do something to get it done. I appreciate the responses. Thank you very much.

[Plymouthy Adams]

hydronic heat is not all floor piping and or baseboard mounted radiant units.  In my case I will expound a bit and state my heat exchanger is part of my normal AC ducting.....the heater is a good distance from the house and the water is circulated to the exchanger on call to heat by the thermostat.  The outside unit also turns itself off and on by demand of the system via an aqua-stat, the fire box is airtight until call for the water to be heated whereupon it opens the damper and force  feeds air into the firebox and if no call for heat will sit banked for days on end.   No mess in the house, wood, ash or smoke, no risk of chimney fires and I truly am safe to go off and leave the fire anytime so peace of mind here is everything.  Not trying to sell you on this system. just explaining there are other means of adapting hot water to heat your home.   

Edited April 4, 2023 by Plymouthy Adams

[kencombs]

Mitsubishi is the undisputed leader in mini-splits, especially the Hyper-heat units.  But that expertise and performance comes at a cost.  

[Rodney_Hamon]

I have an old hodge podge house in New Mexico that is potpourri Adobe, cinder block and wood framing. Half the floors are brick on sand/dirt. The other are floor joist with about 1-2 feet air space underneath. Open cathedral ceiling in half the house. There was no central heat in the beginning which goes back over 100years. No cooling and just wood stoves. I rebuilt and added new windows, doors, insulation and went to pellet stoves. I added the Mitsubishi twin duct 10 years ago and have 2 heads on either end of the house. The cooling is great and it filters the air decent from the intense pollens and Forrest fire smoke.  If the room is smaller the heat function works better. The front room where the cathedral ceiling is the head struggles to push that warm air out. It is disappointing in that regard. The pellet stove with a battery backup is essential for when power goes out. I have an all electric house supplied by an electric coop. I live in a rural area. The heads need to be cleaned once or twice a year by having the filters removed and hosed out. No big deal but it has to be done. The condenser outside needs to be sprayed with simple green and hosed off at least once a year to remove dirt from the cooling fins. So maintaining these units are essential and can cost if you have the installer do it. I have 2 houses and 2 studios that have these systems. For the most part I am pleased with their performance. As it gets hotter I sure do enjoy the cooling function. Also, the condenser must be placed on the south side of the house in order for the heat exchange to work more effectively. My units work on 220, it’s own dedicated circuit and are effective in winter to 32 degrees. After that they struggle and I turn on the pellet stove or light a wood stove. Insulation and passive solar design is the best really. And I’ve heard good things about Trane units for houses that have central ducts. Sorry for my long report. 

[Dan Hiebert]

It gets too cold in this region to rely primarily on heat pumps.  I know of no one in northern Maine that uses solely heat pumps.  Most install the split units to alleviate other fuel costs, something like over 75% of Maine heats with fuel oil.  Although touted as the cheapest in New England, our electric is too unreliable (Maine has among the worst outage rates in the Nation), and 1/2 of the State does not have natural gas delivery.  I primarily use coal in winter, many use wood.  A lot of residents up here installed those split units when heating oil shot up about 15 years ago, but only as supplemental heat so their primary heat source wouldn't have to work as hard.  I've been researching split unit heat pumps for a few years, there are manufacturers that list 10-15 degrees as the cut-off temperature for their units to heat in the winter, but I believe that is because up here they have to include an auxiliary internal heating unit for the heat pump to draw from, otherwise it will only work for maybe the first and last month of "winter".  Cost is what is holding us back, I anticipate that the way things are going we'll have to convert to something other than coal / oil for heat in the future, but for now it is still far from cost effective. 

[Veemoney]

On 4/4/2023 at 10:35 AM, oldodge41 said:

add an ac unit as I am trying to get away from window units to cool the entire house. 

Just some thoughts.

My only experience I can add here is in regard to AC where split units were used on most of the portable office containers I used. They either froze you out or had a tough time keeping up and the fans on some were noisy. If you closed a door your room would heat up and the other room would chill up.

First home I purchased had boiler heat with 1 window AC in the kitchen. It was a solid brick home on a slab with joists and baseboard radiators. My friends called it the adobe because it would bake you during the summer even with the AC on.

I moved the 1 window AC unit ~15-18k BTU to the utility room where the boiler was and installed it in a window close to the ceiling. I purchased tin ducting from Home Depot and fabricated it to attach to the front blower portion of the AC unit.  Cut 2 holes in the ceiling to route the cool air up and through ductwork I ran in the attic using registers I installed in the ceiling to the far rooms. 1 line branched to feed the living, dinning and kitchen, the other the bedrooms. I ran no ducts for the return and just left the door of the utility room open to draw return air to the AC unit as it was designed. That 1 unit could not be turned up all the way after that or it would freeze you out.

Since you have duct work in place already for heat, no matter what system you decide on it may be better to consider tying it into the ducts you already have for better more efficient distribution. This keeps the fan noise away as well. You would simply connect whatever system you chose to existing duct main and install a shut off damper somewhere behind the connection to keep cool air from backing into the furnace.

[wakeman]

I'm in PA too. Keep the oil heat add the heat pump. Heat pump will heat your house more efficiently down to around 30, then below 30 the new thermostat with an outside temp probe switches to the oil. Best of both worlds.. Electric back up heat is the most expensive.  I have sent several people down this road, My brother in law paid for his new heat pump in 3 mild winters, savings on oil.  A heat pump basically  is an AC unit with a reversing valve. Don't buy just an AC unit if you already have duct work. My 2 cents.

[JBNeal]

Grandma had a heat pump in her small house built in '89, and it was very economical and effective above 50°F.  Once it dropped into the 30s, she was shivering; this happened rarely in Central TX back in the 90s as winters were fairly mild for many years running, with the exception of December 1990 where it was in the teens for a week.  When the AC pooped out after 14 yrs, Dad convinced her to switch back to conventional electrical resistance heat, which was OK for her for many years.  When she told me to move into the house when she transitioned to the assisted living center, I refurbished the propane space heater that she never fiddled with, and that 6 brick Dearborn can heat the whole house nicely.  I have convinced 3 other elderly neighbors to switch to propane heat chimney inserts, which has proved to be a life saver as we have had some brutal winters here lately, with days long periods of no electrical service.

[oldodge41]

I have spoken with three dealer/installers.

 

First guy - Listened to my desires and replied: Definitely heat pump - I've installed thousands in our area. The new ones are good to -5F before efficiency drops. No backup heat necessary. Heres the price let me know when your ready.

 

Second guy - Listened to my desires and replied: Let me come to your home, I will do a complete heat loss study, calculate heating and cooling loads and then we can discuss options that will work. We discussed several options including, stand alone heat pump,  heat pump with fuel backup, heat pump with electric backup, fuel primary heat with stand alone A/C. Seems very knowledgeable and gave me a ballpark price range. He will be here Tuesday to do the heat loss study.

 

Third guy - I can be at your house to talk to you in 4 hours. He came with a plan for ductless mini-splits, which I don't want for several reasons. We discussed other options which he admitted he wasn't too familiar with, but he took a bunch of pictures and measurements and said he would talk with their more experienced estimator about other options and get back to me middle of next week.

 

My take:

First guy, excellent local reputation, very easy to talk to, very knowledgeable, very responsive. He is the president /owner of the company. Gave me his cell said call anytime. Not too interested in discussing options was the negative for me. Overall - cautiously optimistic

 

Second guy - Open to options, wants to get it right the first time, he is an estimator/salesman, company has an excellent local reputation, ballpark price was in line with first guy. I was impressed with his knowledge of every system I inquired about. He overwhelmed my wife and she said he is making this too complicated. I like the details, she doesn't. Overall - Looking forward to his recommendation

 

Third guy - Not well versed in options, out of his comfort zone talking ducted systems. Easy to talk to, eager to please, but possibly lacking knowledge/experience. Overall - hoping the more experienced guy gets involved. If he is the same, they are a no-go.

 

Thanks everyone for your experiences and opinions. I'll keep you posted as I move ahead with this.

[oldodge41]

The quotes are in:

First and second guy are within a couple hundred dollars of each other, although each spec'd out different equipment. The third guy was right at double the other two prices. Looks like I will go with the second guy since he has a much more comprehensive quote, and facts / calculations to stand behind his recommendations. 

Looking like it will be a Mitsubishi 36000 BTU (3 ton) Hyper Heat outdoor heat pump paired with an air handler for the indoor unit. I am adding auxiliary heat strips to the air handler as a "just in case we get a rare extended sub zero stretch of weather". The plan is to heat and cool with the heat pump 12 months a year, but have the aux electric heat programmed to run only if absolutely necessary, possibly only with my intervention. 

Next steps is sign a contract and place a deposit on equipment, then get it scheduled and done. It is supposed to be a one day demo of the old oil fired system and installation of the new heat pump system.

[oldodge41]

Installation started yesterday. Demo and removal of old furnace complete. Outdoor unit set in place. Power wiring run from panel to equipment location. Refrigeration line set was run from outdoor unit to a location near where indoor unit will be set. Installed new thermostat and removed the old one. Today will require converting the air handler from horizontal mount to vertical mount, setting indoor unit, connecting refrigeration line set, vacuum test, etc.. Installing breakers in electrical panel and terminating at equipment. Then initial testing and commissioning.  Another full day, at least, I am sure. I think the estimator blew it on installation as he stated it would be a pretty easy one day installation. I will be surprised if it is running at days end on day two, unless they send additional manpower. So far it has been an installation tech and a helper. I asked why they didn't do the horizontal to vertical conversion at the shop, where it would be easier, and it will take some time, doesn't look hard, just lots of tedious steps, and they said because the estimator missed it and the kit won't be here till today. Fun, fun, fun for a doi-it-yourself guy who has never hired anything like this out before.

[oldodge41]

Day two of the one day installation is complete. Still no HVAC. Not much accomplished today. Installed the kit to change the air handler from a horizontal to a  down flow unit. They seemed very surprised that the unit won't just bolt up to the existing ductwork, even though we saw it coming early yesterday. Actually discussed this distinct possibility with the estimator when he was here. Progress was halted until an adapter is fabricated to mount the air handler to the existing ductwork. Supposedly tomorrow is to be "the day". We will see. They are very apologetic, I keep telling them to take whatever time they need to get it done right. I am not paying by the hour. Same install tech today but a different (better) helper. 

[oldodge41]

Day three of the one day installation is complete. I have a functioning system. So far so good. They had to remove a door, a piece of framework and some trim on my furnace enclosure/closet to get the air handler in place, so they have a carpenter coming Friday morning to redo the trim. That should wrap up the install. I believe it was a learning experience for all involved, and I believe my technical background came in handy a few times. Made a couple new friends and spent a bunch of money, just about like with an old car. LOL