changing from OIL to heat pump system... HELP
Hi, I am new to this, just got this link from FINE HOMEBUILDING magazine, March 2007. The question asked in the magazine is my question exactly! The question: [FONT="Arial Black"]"I have a 2700 sq.ft house heated with an oil furnace. I plan to switch to a heat-pump system, but because of the cost of this system, I want to get some opinions on the best brands to consider." [/FONT]Our house is three floors, basement, middle floor and top and is 2600 sq. ft. The basement will have a small living room, bathroom, two bedrooms and a utility room. middle floor will have a bathroom, kitchen living room and bedroom, top floor will have bathroom and bedroom. We are undergoing this remodel in April. Currently we have a oil burning furnace that is a DINOSAUR and getting anyone in this little remote town to fix it is a joke. We are holding our breath it gets us through the winter. It has broken down twice, costing hundreds of dollars to fix, not to mention the high cost of fuel. We estimate it costs us around 3.00 an hour to run, depending on current diesel prices. So, here's the question. We were told about the heat-cooling electric pump and how cost effective it is over the long haul. It is quite expensive and we want to make sure it is really what we need. We live in an area where there is only propane, no gas. Using this funace would elimate having to have a huge propane tank. PLEASE, can anyone tell me about these furnaces, which brand is good and if this is what will work best in a very cold climate. Our temps in the winter are sub zero in the coldest parts of winter, and summer is nice around 90 degrees. This is mountain weather at it's best. We probably would use the cooler much, only a couple of days during the winter. THOUGHTS are SO appreciated!
What are your local electric rates? Around here, they are very low. People can knock 2/3 or more off their heating bill by using a heat pump & electric backup over oil. And we get plenty cold. Knowing where you are and local costs would help us advise you.
Unless you have at least a 200 amp electric service, you would have to upgrade but again around here, that's a 1 year payback. As long as you have a good duct system and get a good install, about any system would do a nice job. One thing to watch is the duct design as heat pumps need to move a lot more air than an old oil furnace.
BL is correct in that the installation and ductwork is much more critical than the brand of equipment. Some brands may have different features which you may or may not want or need, but the overall operation is prety much the same with all of them. (Think Ford and Chevy. Both make good trucks, which one has the features YOU want.) Most brands have different levels from basic/entry level to high end with all the bells and whistles. When comparing brands, make sure you are comparing apples to apples, and looking at models at the same level. Find a contractor that is willing to listen to what your needs are and let them recomend a system that will meet those needs.
Where are you? Are you done yet? I got ONE more call for you.....
If you don't want to use a big tank for oil or gas and theres no natural gas supply to your area and you said your cold temps get down to subzero than I would definitly go with heat pump and an electric furnace as emergancy heat
Knowledge comes with experience
Your situation is very similar to my own, as I changed from oil to a heat pump 2 years ago. The biggest factor between oil and heat pumps is the size heater you can buy. The largest residential heat pump is typically 5 tons (about 60K btu). How much heat does your house need (and I wouldn't base it off your existing furnace, as mine was inefficient and had a 138K BTU input capability. I only needed about 50K -65K BTU).
Are you redoing the ducts? A heat pump must move more air than an old oil furnace because it typically operates with air that isn't as hot. More air means larger ducts are required. My existing duct system could support a 4 ton heat pump, but not a 5 ton. I changed my old windows to new well insulated ones and that reduced the heat loss so that a 4 ton would work.
If you need more than 5 tons of heat, or you have a duct size problem, consider two heat pumps. This will also help if you have no return duct on the top floor. I really wanted a 2 ton heat pump for the top floor and 3 ton for the basement and 1st floor. But I couldn't easily add the air trunk duct to the top floor. So I made do with a 4 ton and it is actually working well but two upstairs rooms are a little cool (and too hot in summer). I'd definitely get an upstairs air return for cooling in summer if you don't have one now.
You can also make up for lack of heat capacity with the auxillary heating system. This is required during the heat pump defrost cycle, but is also a backup heat source if the compressor fails, and it supplements the heat pump as it colder outside and it is making less heat. This heat would most likely be electric heat strips in the air handler in your case. You'd just need to go to the larger allowed sizes if you need more heat. This is also the most expensive heating source, so you really have to think about costs if your electricity is more than about 9 cents per KW-Hr and you'll be relying on these suplemental strips for much of the winter. Propane is usualy the second worst choice cost wise, so you may be able to go even higher in electrical rates and come out ahead.
When it comes to brands, there are a few that can have some difficulty in obtaining parts (ask your installer which old systems they have difficulty in getting parts for, or parts that cost an arm and a leg). The other main descriminator is technical features, and the Carrier Infinity (or its clone the Bryant Evolution) system has some amazing capabilities that you can control if you know what you want and understand the parameter settings in the thermostat. It is also a good way to do zoning, which you'll most likely need if you pick a central heat pump instead of two systems. These are a little different to install, so I'd pick a contractor that has some experience with them if you choose it. Its thermostat only requires 4 wires (instead of 8 or more in most others), so if you have 4 now, this is one less wall to fish a cable through.
follow up/response to heat pump conversion from OIL furnace
Thank you everyone for helping me with my questions about changing from heating oil to an electric heat pump. To answer some of your questions:
1. the home is located in Odgen Valley, 40 minutes outside of Salt Lake City UT. By COLD tempatures, I mean anywhere from 0 to -20 in the winter. It's not always that cold, but is has been below zero more than 30 days since the winter began.
2. Yes, we plan on doing duct work. The basement has low ceilings due to the current duct work. We need to move the ducts to the side of the walls. We will also be moving the furnace from it's current location to a new furnace room.
3. Electricity costs are average to a bit lower than average in our area.
4. This is NOT a full time residence so we need to have a trust worthy system that will not break down. If it does, we will have frozen pipes.
5. I would love recommendations on a brand(s) to consider.
Thanks so much! We appreciate it!
First, system(s) sizing.
Originally Posted by heidi kaminski
Second, design. ... ground source or air.
Third, equipment and back-up selection.
Fourth, annual energy cost estimate ___ http://www.utahpower.net/Article/Article50951.html
ClimateMaster for water (ground) source heat pump in your locale.
It's Not Rocket Science, But It is SCIENCE
with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE
Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities
Make sure the contractor you pick does a manual D on the house.
Originally Posted by heidi kaminski
I think you'd be better off selecting your contractor and not the brand. Your contractor will have experience with their brand and may not have a lot of experience with the brand others may think is best.
I would love recommendations on a brand(s) to consider.
A top quality system is only as good as the installation. A 'lousy' brand will perform better if installed correctly than a 'top' brand installed poorly.
you will not be sizing your heat pumps to keep up with the heat loss of the house since you will need a much smaller size in air conditioning season then you will in heat
You will have a heat pump with electric back up and your back up will run quite a bit when the temps get cold
Any and all equipment you buy can break down there isn’t a brand out there that doesn’t need to be serviced and there isn’t a brand that wont break
You need a reliable contractor
There are safe guards you can put in place in case the system goes down ie… a thermostat that will call you or the contractor to inform you that it is not working
This wont do you any good if the power goes out unless you have a backup generator
The key here is to get 2 or 3 companies out there to look at what you have and to talk you through
Ask you friend and family in that area if you have any who they deal with and if they are trustworthy
It cant be stressed enough that you need a good install so make the key part of this project finding a contractor that does top notch work
many factors to consider, but have you thought of using both? In my own house, I added a heat pump to the existing oil furnace and used the oil as the back-up. This required duct modification and re-wiring the furnace, but it has saved me a few G's in the last few years with respect to my heating costs. Your existing system and home are likely a LOT different than mine, but I personally love the dual fuel option. I now spend about $700 more in electricity per heating season, but I went from burning five tanks of oil per year to just one tank per year, very significant savings, especially with the cost of oil these days. Find a local guy that really knows his stuff and see if this may be a viable solution for you.
I AGREE WITH SAM. IF IT WAS ME I WOULD SELECT THE DUEL FUEL, I SET THE OUTDOOR TEMPETURE SETTING AT 40 DEG f TO SWITCH HEAT PUMP TO SECONDARY HEAT.
I LIVE IN TOOELE UTAH AND THERE IS NOT A LOT OF HEAT PUMPS IN THIS AREA, AND THAT MEANS THERES NOT ALOT OF HEAT PUMP TECH. OUT THERE, SO BE CARFUL ON WHAT CONTRACTOR YOU CHOOSE (OUT OF MY AREA).
MY OPINION (FROM THE UNITS I HAVE SEEN) IS TO STAY AWAY FROM A RHEEM OR RUDD HEAT PUMPS BECAUSE THERE IS A VALVE THAT IN ITS NORMAL POSITION IS IN THE COOLING MODE AND A SOILIOID IS ENERGIZED TO SWITCH TO HEATING MODE. BASICALLY WHAT IM SAYING IS THAT I WHOULD WANT A HEAT PUMP THAT IF MY SOILINOID FAILED IT WOULD FAIL IN THE HEAT MODE.
ABOUT 80% OF THE HOMES IN THIS AREA INCLUDING NEW CONSTRUCTION HAS UNDERSIZED DUCT WORK DUE TO OUR ALTITUDE. SO GET A CONTRATOR THAT WILL DO A DUCT CACULATION, AND A HEAT LOAD CACULATION.
AS FAR AS SECONDARY HEAT THE COST MAY CHANGE.
ELECTRIC FURNACE: RATES GO UP YOUR STUCK
OIL FURNACE: ODERS MAY BE AN ISSUE
That is an excellent suggestion too, especially for very cold areas. I considered that for myself also, since I already had the oil infrastructure. But my tank is buried and 40+ years old, and I feared the liability of an oil leak (I live next to a lake). And it rarely gets below 30F here, so the heat pump does most of the heating all the time.
If your tank is in good shape, or the ramifications of a leaky tank aren't huge, oil may be your cheapest source of aux heat when it is less than 25F - 35F outside and the heat pump by itself is not enough.
The only thing to consider is with dual fuel, the heat pump turns off when the oil or propane heat kicks in. With electric backup, both the backup and heat pump can run at the same time. Finally, most heat pumps should not be run below 0F (and the heat they make at that point is getting pathetic anyway), so if you have much time below 0, the aux heating system is going to be doing all the work (so calculate costs accordingly).
You beat me to it, definitely look at duel fuel.
Originally Posted by Sam-the-man