heat pump vs conventional electric furnace

[hvacdaughter]

I have an alllll electric home with approx. 1100 sq ft. My electric bill was almost $400.00 last month. Outrageous for this size home in the Dallas area, where winters are fairly mild. My furnace is original to the home (built in 1984)and I am getting bids on a new system. My father purchased a 10 seer Amercian Standard A/C about 3 years ago for me, so that is fairly new. I didn't lower my electric bills as much as I hoped when that was put in. The evap. coil is 5 years old and is close to being out of warranty. It's the cheapest model you can buy! (We didn't put that in.) I've also found out that the plenum size is about 20% smaller than the coil, so that's a problem as well. I'm hoping to buy a system with at least a 14 seer and an HSPS of 9.

My dilema is that I am looking at a heat pump vs a conventional furnace and my father is very against heat pumps. He says they are fine for Florida, but not Dallas and they won't save me any electric $$ since the compressor runs all winter as well as all summer, and he doesn't feel that I need a new A/C at all. However, the electric furnace draws 60 amps while the outside unit compressor will only draw 30 amps. Plus, the heat pump would only use the electric strips as a back up on really cold days. I know the existing system is far from efficient and I'd rather spend the money on a new one than pay the electric company ...question is...which one do I buy..a heat pump or a conventional furnace? BTW--my dad is retired and not really able to do the work, however, he's still able to give advice.... :)

I appreciate any advice that can help me compare the two systems to have lower electric bills and increase efficiency -- that's the goal and the ultimate bottom line!

[Mod01]

Moved to residential forum.

[smokin68]

Ist off, spend some money on insulation for that small home.Where did you get your 60 amps vs 30 amps...off the breaker/disconnect size? the compressor won't draw 30 amps unless it's a big one.After you've insulated, have a load calc done to see what size a/c-heat you'll need.After you determine the sizes, have your duct system checked to see if it will handle it.Then go with the highest seer heatpump you can afford. With insulation added, a properly sized system,and the correct ductwork,you will save money.Even $100 a month should pay you back fairly quick. JMO


PS...besides the insulation,good windows/sunscreens can make a large difference in heat gain/loss.

[BaldLoonie]

Sorry pops, I vote heat pump. In your area, you would rarely need backup heat. At 32, most heat pumps are 3 times the efficiency of electric strips. Since you mostly are warmer than that, you should see a healthy savings in your heat bill.

Today is low to mid 20s, mine is set at 67 and cycling with no backup.

[airworx]

your father is listening to some quack a/c guys that has little knowlge. now your telling me that the weather is far warmer in florida than in texas, heck might as well ship all the heat pumps to the desert. lack of knowledge will come out of every mouth that doesnt know, just like zoning systems, variable speed air handlers and furnaces and heat pumps are no good. wonder why there made.

if you want to save money a a high eff heat pump will save you maoney year round.whatever you go with make sure you get a variable speed furnace, that will increase the cooling and heating eff, remove more moisture which allows a warmer thermostat setting and anything over a 13 seer will not get that rating without a var.speed funace.

[hvacdaughter]

Thanks for the great info! So far, heat pumps are winning! Good info on the variable speed. My Dad is old school and he IS an A/C guy--he's just never liked heat pumps! Regarding the insulation, etc. - Had already added attic insulation, am having a load calc done with results to come Monday, great idea about the windows, too! Regarding the duct work...have read on the internet that due to the higher pressure of air flow with heat pumps, usually the existing duct work needs to be re-done for larger diameter/volume.... one of the guys that gave me a quote (I won't say which company) says that isn't so.....their bid did not include new ductwork, only repairs if needed during installation....although he did recommend larger diameters for the bedrooms as the existing ones are too small. I have a 6 diameters in each bedrooms and he says it should be a 7, but other than that, no replacement of ductwork.

Thanks to all!

[Jultzya]

Originally posted by BaldLoonie
Sorry pops, I vote heat pump. In your area, you would rarely need backup heat. At 32, most heat pumps are 3 times the efficiency of electric strips. Since you mostly are warmer than that, you should see a healthy savings in your heat bill.

Today is low to mid 20s, mine is set at 67 and cycling with no backup.

Above is your final answer!

[aircooled53]

Well, for one thing you can Not install stand along electric furnace in Texas anymore you would either have gas furnace or heat pump. State of Texas passed bill last year and we can no longer install them .. Ask Steve Wiggins on this site and he can give you more information about this.

I would state about 80-90% of the new construction around Keller,Grapevine Southlake,North Richland Hills, Saginaw,Eagle Mountian all use heat pumps.

Some of the rural area's also use ground source heat pumps,Arygle,Newark,Boyd,Azle,Grandbury and Lake Dallas..

[docholiday]

I's ask pops if he wants to pay the electric bill. As with alot of a/c guys who dont like heat pumps, it's more often because they simply dont understand them.

Frankly, you would have to be nuts to go with an electric furnace any place BUT florida.

[hvacdaughter]

Any thoughts about whether the duct work has to be replaced going from the electric furnace to the heat pump? One company included all new duct work in their quote and another said new ducts weren't necessary, but would repair in spots if needed. My understanding is that the pressure is different and the duct work I have may not be sufficient for the heat pump. What do you think?

Thanks to all for your assistance!

[Senior Tech]

Just an observation...generally when someone, (and I used to be "someone") doesn't like a peticular type of equipment, in this case, heatpumps, it's usually a sign that they don't fully understand them. I learn more about them everyday and am almost to the point where I'm actually considering putting one in myself...and I live in Illinois.

[hvacdaughter]

You guys have convinced me!! A heat pump it will be! The only questions left are the one above about the ductwork, and this one...what do you think about aluminum coils vs copper coils?

__________________
What a great game!!

[docholiday]

It really depends on the sizes, you cant answer that from here. IF the output of the old electric furnace is near that of the heat pump you may be ok but really you need to be able to move 400 cfm per ton. For instance, if you buy a 3 ton heat pump you would need to move 1200 CFM of air. Your installer should be able to calculate this. If he just says it's ok without doing the math, then he isnt your man for the job.

[dash]

You are getting a Manual j load calculation to size the equipment.

You need a Manual D calc. to re/design the ducts if needed.


BTW ,if the ducts need to be larger for the heat pump,they are too small for the A/C.
The cfm required is similar for each,plus in heating the indoor coil is dry so less resistance to air flow,so on the same speed you'll get more cfms in heating than cooling.

[James 3528]

Most coils are aluminum coils and copper. The filter matters more.