Hybrid Heating units

[tunnel_rat]

Yea, the only 80+ we put in seem to be change outs in the boss's own properties which already have them. The 90+ dual fuel is a good choice in this area, and running a PVC flue is not an issue for pros.

[HomeowneNOVA]

I understand that the gas rate might be low compared to other areas, but isn't a HP more efficient? Would you recommend them that I just buy a regular AC and furnace?

The gas rate after the first 100 th is $.26.

I agree with you that something is off with this contractors but they come referred by the companies and have the right credentials NARE, etc. Maybe I am misunderstanding them and they do not want to do the work if they do not get the project but you are right something does not sound right and I guess that is wny I seeking your advice. I will keep looking

[speedymonk]

Your rate for gas is four cents a therm cheaper than mine. What is your delivery charge? Mine is 78 cents a therm, making my gas really $1.08 plus the $8.50 customer charge.

[beenthere]

Sorry. What is your average charge for gas, including delievery and tax.
Plus, what is your electric rate.
Average them.

[acmanhoney]

I work NOVA and sell infinity, my customers love it with superior humidity controll
and i still get amazed at how quiet it is, infinty controll is very nice. i would do 96% in my house with 19 seer heat pump, carrier is also kickin out a $1100 rebait, 4-6 weeks, we sell trane and carrier. go with a good company that can size install and maintain your COMFORT system to max out efficiency and your comfort. choose by comfort,efficiency then price


ps hybrid works great in metro area with our high humidty, hot summer, sometimes freezing winters. people say they love it
check out hvacopcost.com

Alexandria VA

[tomgeer]

I am in the process of replacing the AC and furnace in my house. I live in Nothern Virginia. The contractor I have contacted are pushing this type of unit, a hybrid heat pump (HP with a gas furnace back up for temp below 40 degrees). I have looked at carrier, Trane and Lennox. I would like to know if anybody has any experience with these units and their performance.

Also, all have indicated that I should go with a 80+ furnace because a higher efficiency unit, 90+, will require a new PVC exhaust. Does it make sense to go with this hybrid unit with a 80+ furnace?

Any advice will be welcome.

My system is a Lennox G60uhv with a hp15. Your pay back is faster. But I do recomend the two stage v-speed furnace. 80% will work fine and pay back is faster, 90% cost more up front but pay back is longer.

[platchford]

We definitely would need to know what your total cost per therm for gas and also your total cost per kWhr is for electricity. If you pay delivery and fuel charges add them together... or better yet take your total gas bill for a month and divide by the total therms... do the same for electricity. Without that information we would be simply guessing as to whether its a good idea or not.

Also, make sure whatever company you choose properly performs a load calculation or 'Manual J' for the house. No matter how good the equipment and installation, if it is not properly sized then its not going to perform at peak efficiency.

As far as the 80% or 90% efficiency, the value of the higher efficiency would ultimately depend your balance point and how frequently the gas furnace is expected to run. You have to figure the heat loss of your home as well as the expected increase in up-front cost by going 90+ and compare that to the potential annual energy savings. If your gas heat is only running 20% of the time and costing you $300 during the heating season (assuming a small system) then you will be saving about $150 per year. If, on the other hand, your gas heat is running 25% of the time and costing you $600 during the heating season (assuming a larger system) then you will be saving about $300 per year. Obviously this impacts the return on investment of the difference in up-front costs of the less and more efficient units.

[tomgeer]

We definitely would need to know what your total cost per therm for gas and also your total cost per kWhr is for electricity. If you pay delivery and fuel charges add them together... or better yet take your total gas bill for a month and divide by the total therms... do the same for electricity. Without that information we would be simply guessing as to whether its a good idea or not.

Also, make sure whatever company you choose properly performs a load calculation or 'Manual J' for the house. No matter how good the equipment and installation, if it is not properly sized then its not going to perform at peak efficiency.

As far as the 80% or 90% efficiency, the value of the higher efficiency would ultimately depend your balance point and how frequently the gas furnace is expected to run. You have to figure the heat loss of your home as well as the expected increase in up-front cost by going 90+ and compare that to the potential annual energy savings. If your gas heat is only running 20% of the time and costing you $300 during the heating season (assuming a small system) then you will be saving about $150 per year. If, on the other hand, your gas heat is running 25% of the time and costing you $600 during the heating season (assuming a larger system) then you will be saving about $300 per year. Obviously this impacts the return on investment of the difference in up-front costs of the less and more efficient units.

ok, All that to say --- 90% is more money up front and pay back is longer. 80% is less money up front and payback is sooner. In my area, $1,100 for a HP upgrade with new system. This WILL be seen in energy savings over 2 - 2.5 years causing early upgrade payback. Now look at your total system pay back. How many people can say today " TOTAL system payback in the life of the system? Most Co. want you to add what you will pay for repare, fig. out your enegy usage and cost. add all together. now do same with the new furnace and subtract the two. this determans your system payback. ( what ever the thoughts are, have a long or short "J" done. Compare three aples for aples bids, check rep of Co. and pick WHO YOU WANT IN YOUR HOME>

[mwjhvac]

This a figure I did for a customer the other day.

1 U.S. therm = 29.3kwh
Cost of 1 therm of electricity delivered by utility =
$0.043 x 29.3 = $1.25 therm

Cost of 1 therm of heat energy supplied to the house by the heat pump to 25 degrees = $1.25/2.5 = $0.50/ therm

C.O.P.=2.5

COST OF GAS ENERGY SUPPLIED BY FURNACE
The furnace is 96% efficient
Cost of 1 therm of heat produced by the gas furnace =
=$1.10/0.96 = $1.14/therm

Carrier Infinity Hybrid Heat

[s7m8a]

That company you're dealing with sounds like a "jack-leg" outfit to me. I hate trash talkin' about the competition 'cause most outfits do good work and are out for their slice of the pie. You would be shocked by how few companies actually do load calculations. The company I work for requires one be done on estimates and certain service scenarios. Check the company out. Check out a few companies for that matter. I hope you get the right equipment & good workmanship at a fair price. Customers put a lot of trust in companies to do the right thing. It's unfortunate that some companies take advantage of that trust. It makes it harder for reputable companies to regain that trust.

[gasoilair]

Where is the furnace going to be installed? Around here, a lot of companies will steer clear of a 90+ if it's going into unconditioned space, like an attic. Too many condensate problems.

If it's going in the basement, I can't see why he would suggest against a 90+. There MUST be a good reason, and running the venting is a weak excuse unless the outside wall is a hundred feet away through finished rooms.

I think you should get him on the phone and ask him what his reasons are. Everyone's install is different, so it may just be something with your particular job.

Get some other estimates and see what others have to say, and pay attention to how they size up your particular job. If they grab the info off the old equipment and spit out, "Okay, you need blah blah blah size gear.", then a different company may be in order. A pro will size the new equip by the size and conditions existing with the house and not use existing equipment ratings.

[gary_g]

Your rate for gas is four cents a therm cheaper than mine. What is your delivery charge? Mine is 78 cents a therm, making my gas really $1.08 plus the $8.50 customer charge.

Good point, Speedy. Nobody is figuring in the delivery/distribution charges for the gas.

[gary_g]

This a figure I did for a customer the other day.

1 U.S. therm = 29.3kwh
Cost of 1 therm of electricity delivered by utility =
$0.043 x 29.3 = $1.25 therm

4.3 cents per kw-hr is dirt cheap. Does that include transmission and distribution charges, or is it just generation?