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View Full Version : Are Heat Pumps worth it in New England?



JosephCB40
Nov 12, 2008, 12:34 PM
I live in Southern Connecticut and I have been told, after my yearly checkup, to replace my two 30 year old forced air oil furnaces. With oil prices up and down so much, our contractor suggested a dual fuel heat pump/oil furnace to help protect against future price spikes. But the heat pumps from all the major manufactures (Train, Bryant) seem to have suggested balance points of 40-45 degrees. We keep our thermostat at 60 and really only need the heat once the temperature goes below 45 degrees. In this case does it really make sense to get a heat pump? Does anyone know of a heat pump that will work well in cold climates or down to 20 degrees? Thanks!

hvac1000
Nov 12, 2008, 01:40 PM
They can be. I suggest your contractor provide you with the aprox energy savings by having a heat pump installed using your temps you use (60 degrees).. All else on this end will be guess work. There are heat pumps that will provide heat below 20 degrees but the good ones cost big $$$$.

dac122
Nov 13, 2008, 05:54 AM
I live further north than you and my older York 8 HSPF has provided all my heat this season, and I set my indoor tstat to 70. Somewhere below 30 degrees it begins to struggle to keep up. So that 40-45 degree recommendation is not correct. In fact, this morning when I left home it was 42 and the HP was easily providing all my heating needs.

Think of a heat pump as a supplemental heat source that helps in the shoulder heating season. You always install a heat pump with an auxiliary heat source such as heat strips down south, or a furnace in the northeast. When you hit the heart of winter, i.e. below freezing, its not your only heat source, but it could be a major source of heat for your locale given you keep your tstat set so low.

To be fair, that 40-45 degree balance point is not completely wrong. To clarify there are two balance points: economic and comfort. Because the output air isn't all that warm, and at lower temps not as warm as human skin, some folks just don't like a heat pump over a furnace's warmer output air. So your contractor is reciting a safe comfort balance point. The economic balance point is much lower than that as a heat pump can still provide some or all your needed BTUs well below 40.

There are cold climate heat pumps out there, but they are so expensive, and are from unproven companies, I would not recommend you consider one. But rather as said, consider a heat pump to supplement your heating costs.

I agree it could be a hedge against fluctuating energy prices. If you can provide your electricity KHW costs including taxes, your current price/gal oil and your furnaces BTU output I can respond with a possible scenario that might help clarify how you calculate the operational costs/savings.

agatto2
Dec 7, 2008, 04:08 AM
Just to add a bit of information

Heat pumps are difficult to work on. Most In the North East do not understand the concept, and have not installed many heat pumps. Thus you will have a bit of trouble finding and keeping a service company. Especially if an emergency comes up.

The only way I would consider a heat pump is if your community has their own power plant and the electricity is cheap. I know that in Jamestown NY everyone has electric heat because they have a co-op electric plant that produces dirt cheap electricity

Hope that helps in your decision

Tony

KC13
Dec 7, 2008, 07:39 AM
I live in the Cincinnati area, and I have a Bryant R-410A heat pump system, installed in March '07. The Evolution control system keeps a log of all system cycles and/or malfunctions. Since installed, the log is showing less than 40 total hours of auxiliary heating. This is remarkable compared to my old R-22 system and attributable to the wider operating range of the R-410A refrigerant. Ultimately, no two structures will have the same "balance point", as there are many variables in the relationship between the output of the heat pump and the heat loss of the structure. Ask your contractor to provide comparisons between R-22 and R-410A to assist you in deciding if a dual-fuel system is right for you.

hvac1000
Dec 7, 2008, 08:17 AM
wider operating range of the R-410A refrigerant

When we lab tested the R-22 verses the R-410A machines there was no difference in the operating range of the refrigerants or the heat produced since that is limited by the units environment. Naturally the equiptment was based on the same SEER and from the same manufacturer (Carrier) Bryant-Payne-Day and Night=same company.

Carrier was in the testing phase with Honeywell the manufacturer of the refrigerant (R410A). R-410A is the wave of the future since R-22 is in phase out.

R-410A has quirks that R-22 does not have but to the certified/trained service person they are minor in nature. To a untrained person it can become there worst nightmear. Higher water absorption capabilitys from the different oil,two part refrigerant that separates and need to be charged differently,higher operating pressures and special tools designed for R-410 are just the beginning.

When Carrier first introduced equipment with the new R-410A refrigerant they would not sell it to just any dealer. The dealer had to be certified to use the R-410A and take and pass a test so they could buy the R-410A equipment. This oversite gave Carrier almost complete control of the sales of equipment and the failure rate was held to the minimum. Now they and other manufactures are starting to have higher warranty returns since most of the HVAC manufactures have decided to sell there equipment to almost anyone weather they are R-410A certified or not. This is just the start of the problems that will come up in the future since the manufactures are more concerned with production numbers than warrenty/trade name protection.

It will take awhile but it will eventually sort itself out. R-410A is a great refrigerant if you know what you are doing with it. Superheat/Subcooling takes on a new and more critical meaning for the well informed.

Myths on R-410A

Myths - R-410A - Honeywell AZ-20 Refrigerant (http://www51.honeywell.com/sm/410a/myths.html)

letmetellu
Dec 7, 2008, 08:53 AM
I would ask you to compare the p0rice of electricity and the price of natural gas and the price of Propane.

In an area of the country where I live the natural gas is cheaper, therefore most people are still using natural gas furnaces.

If you do decide to install a heat pump with 410-A coolant, I would also change the freon lines because of the high pressures. And you never know when a system might have so type M copper somewhere in it, and it is apt to burst under the pressures that 410-A opperate under.

hvac1000
Dec 7, 2008, 01:16 PM
Change the refrigerant lines because they are contaminated with mineral oil and cannot really be flushed properly no matter what they tell you. Mineral oil R-22 and the synthetic oil R-410A do not mix well at all and it can and will cause problems. Just like with R-22 all refrigerant lines must be brazed with rod(no soft solder) and a nitrogen flow during the flame process. These are the minimal acceptable standards
From NATE and code sources.

dac122
Dec 8, 2008, 06:25 AM
The only way i would consider a heat pump is if your community has their own power plant and the electricity is cheap. I know that in Jamestown NY everyone has electric heat because they have a co-op electric plant that produces dirt cheap electricty

Hope that helps in your decision

Tony

Not true. Its all relative.

If you're propane or fuel oil costs are relatively higher than KWH prices than a heat pump can make sense. What you are after is the lowest BTU cost. To do that you need to take into account fuel prices and efficiency of the furnace in question; and KWH price and average COP (or HSPF) of the heat pump. For instance in my area the KWH price is a little high at 16.5 cents (no coops here), but compared to propane at $2.50-$3.00 or fuel oil at $3.50-$4.00, its not so bad.

Cost of 1 million BTUs using heating oil at $3.50/gallon, 80% efficient furnace:
(1,000,000 / 139,000) x 3.50 / .8
= $31.47

Cost of 1 million BTUs using heat pump, electricity at 16.5 cents per KWH, COP 3.25 at 35F ambient:
(1,000,000 / 3413) x .165 / 3.25
= $14.88

In many places where natural gas is available, its low price usually trumps the initial investment of a heat pump. In those places a heat pump might still reduce the overall seasonal heating bill, but the savings wouldn't justify the initial outlay.