DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   HVAC (http://www.diychatroom.com/f17/)
-   -   High Eff. Gas Furnace..? (http://www.diychatroom.com/f17/high-eff-gas-furnace-14389/)

Kyle 12-13-2007 06:52 PM

High Eff. Gas Furnace..?
 
Is a high efficiency gas furnace worth the extra cost? i am looking to get a new furnace, and have gotten quotes for the new high efficiency furnaces. It is hard to believe that the high efficiency furnaces are a must have since all new homes have standard ones. Is it more marketing hype than anything else? My house is 40 years old, and I don't see moving anytime in the future.

Kyle 12-13-2007 06:54 PM

I almost forgot, I have also been quoted for two stage and variable stage furnaces. Are those worth the cost? My house has an even heat and A/C, the only reason I am replacing is because it is 20 years old.

concretemasonry 12-13-2007 07:19 PM

For a 90+% unit, You will probably save about 1/4 to 1/3 of your present gas bill every month. As fuel goes up, the $ savings will be more. With a variable speed fan, you will save additional $ on the AC or at least be more comfortable.

Summit Heating & Air 12-13-2007 07:29 PM

Kyle, Most new homes have standard furnaces because builders, more often than not, have the least expensive furnace installed. Since most people cannot tell a high efficiency from a standard efficiency furnace just by looking at it, a high efficiency furnace wasn't a selling point. That is starting to change with gas prices going up.

High efficiency equipment will save you money over time. It's hard to say exactly how much without knowing more about your home and lifestyle.

Kyle 12-13-2007 07:50 PM

Thanks for the quick reply guys. I have a couple of additional questions.

What is your advice on air filters. What is the best value? The standard 1", the media, or the $1,000 Aprilaire? How about the UV lights that are placed in the ducts?

redline 12-14-2007 09:03 AM

Quote:

Originally Posted by Kyle (Post 80431)
Is a high efficiency gas furnace worth the extra cost?

What were the quotes for the standard and the hi-efficiency?

Is your home fully insulated?

Do you live in an area that gets very cold?

What do you pay per therm for nat gas?

Kyle 12-14-2007 06:21 PM

Redline, here are the answers to your questions:

1) I haven't actually priced the standard units...I have asked the salesman about it and was told the difference in price was only a coule of hundred dollars, and if I planned on being in the house for over 5 years I should get a high efficiency unit. The problem I have is that new houses have single stage, 80% efficient furnaces, so why does my 40 year old house need a two stage variable speed 95% furnace. I am just trying to get some insight from others who are not trying to get a sale from me.

2) My house is insulated in the attic, but I should probably add more. I added an insulation blanket last year, but I have already had ice dams this year.

3) I live in the Chicago area, so yes, it gets cold here.

4) I am not sure what I pay per therm? I believe it adjusts monthly due to market prices...I could be wrong on that one, I am not sure.

THanks

redline 12-14-2007 06:48 PM

Quote:

Originally Posted by Kyle (Post 80667)


1)... difference in price was only a couple of hundred dollars, and if I planned on being in the house for over 5 years I should get a high efficiency unit.


If the difference is only a few hundred dollars then I would go with the hi efficiency as it will pay back the few hundred dollars in the first heat season.


Quote:


2) My house is insulated in the attic, but I should probably add more. I added an insulation blanket last year, but I have already had ice dams this year.


You should have around R-49 in the attic for your area. If it is less than this then it will be inexpesnive to add to it and it will save money and make the home more comfortable.

Do not block the soffit vents with the insulation as it will cause ice dams.

Quote:


4) I am not sure what I pay per therm? I believe it adjusts monthly due to market prices...I could be wrong on that one, I am not sure.

THanks

Most people are paying well over 1.20 per therm and it makes sense to go with the hi-efficiency furnace with nat gas rates only to go higher.

rjordan392 12-14-2007 07:05 PM

I agree that you should see a significant differance in savings on your gas bill with either a 90 or 80% efficiency unit. There will be more savings if you get a AC condensor to match either one.
My home is 57 years old and is a 2 story row home with basement and I was going to go with the 90% unit until the installer told me how he would have to run the furnace vent pipe. He would need to drill another hole through my wall in the basement and not use the chimney (its against code if you have another device vented to it). I also have a deck and he would have to run the vent all the way out to the end.

Well there was no way to accept this and I went with the 80% and the vent for this is allowed to be used at the chimney along with your gas hotwater heater vent.

If you got the room for an additional vent, then I would recommend the 90% furnace. Ask your technician about how he would run the vent. Do not ask a salesman. Also ask about if there are any smells coming out of the vent for the 90% efficiency furnaces. I know of one person who is complaining of a chlorine smell coming out of the vent in the 9 foot driveway, he shares with a neighbor.

kayakertom 12-14-2007 07:08 PM

I recently replaced a 35 year old furnace in my home with a high efficiency one. It would have cost more to replace with a 80% furnace because the original installation had the furnace and gas hot water heater exhausting through the same chimney. Due to code changes, I would of had to have the chimney relined. With the high efficiency furnace, its exhaust is just out the side of the house using pvc.

redline 12-15-2007 04:06 PM

The cost for the 80% furnace and reline of the chimney would be more then the cost of the 90+% furnace. The 80% also has a draft hood that draws heated air from the house and up threw the chimney also costing money.

rjordan392 12-15-2007 09:07 PM

Redline,
Does a 90% efficiency furnace need two pvc pipes? One for fresh air combustion and the other for exhaust. I am also trying to understand about the 80% unit drawing heated air for combustion because a 90% unit also needs air; heated or cold and if its heated, then that goes out the exhaust of the 90% unit; correct?

redline 12-15-2007 09:24 PM

The 90+% furnace has an air inlet from the outside with PVC and also a PVC exhaust. Two seperate pipes.

rjordan392 12-15-2007 11:11 PM

Quote:

Originally Posted by redline (Post 80891)
The 90+% furnace has an air inlet from the outside with PVC and also a PVC exhaust. Two seperate pipes.

Ok, then the 80% and 90% unit would be as you say. Thank you.

carriertech 12-16-2007 06:59 AM

kyle, the 95% var. speed will save 15% over the 80%.If you dont have your old gas bills,I would get them from the gas co. to aide in your dicision.The two stage v.s. is very comfortable and quiet,and does come in a 80% model which is much cheaper and on a smaller home is sometimes a good fit.Any v.s. fan motor will also save a couple hundred a year in electrity but will cost more to replace when it fails. If you do buy deluxe trane,lennox,and carrier all have at least 1000.00 in rebates twice a year.And buy the u.v. if they toss in a good media filter.


All times are GMT -5. The time now is 05:57 PM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved