Central heat/ac question

[vaking]

I am seeking help from the wisdom of this forum.
It looks like I shall have to replace my central heat/AC unit. This in itself is not a very big surprise. I have been in this house for 15 years. Folks before me installed the central unit probably 15 years before they sold the house, so unit is 30 years or so. It earned its retirement.
But when I look at all the options I have - I get confused.
I see a choice of 4-5 major brands, like Carrier, York, Lennox, Rheem.
Each brand has a line of products from basic heat-only to basic heat/AC combo to very advanced units with hybrid heat and heating efficiency reaching 98%. Price tags also vary significantly. So far I have 1 contractor made me an offer and it includes about $7K for basic heat/AC combo installed or $14K for advanced hybrid.
I estimate that the unit I have now (30 years old) has about 80% efficiency and it is probably similar to what today's basic units offer.
Add to this that this is all about heating efficiency, AC effectiveness is measured completely differently and is even more confusing. All manufacurers provide a lot more info about heating aspect than about AC even though units are combo, so they provide both functions.
Do you have personal experience with different brands and products? Any pros here?
Is extra $7k justified for advanced unit?

Thanks in advance.
Alex

[Bruce Cohen]

Alex,
Considering that my Lenox forced hot air furnace and 3 1/2 Ton A/C unit are about 30 years old (the furnace still has a pilot light), I'm a little out of touch with the new stuff on the market.
What is the (your) definition of hybrid unit. If you're talking about a "Heat Pump" type of unit, unless they got really efficient, I'd avoid them like the plague.
I'm sure that conventional HVAC units (separate heating and cooling units) are much more efficient than what I have, but in 30 years we've had almost no problems with either.
The furnace needed an new thermocouple and the A/C unit needed to have Freon (yup, it's that old) added from the landscaper's knocking the cooling hose loose, thereby creating a leak.
If you ask me, Lenox makes great stuff, But I've been told that only Lenox parts fit there equipment, making you a slave to Lenox when it comes to replacing parts.

That's about my .25 cents worth, wish I could be of more help.

Bruce

[JimD]

My house was built in 1999 and the gas pack for the lower unit (a carrier) was a problem beginning early. It was also Freon so charging it got more and more expensive. They tried repairing the A coil once but it seemed to have little effect. Replacing the coil would cost more than half the cost of a new unit. With the rebates last year I decided it was time.

The heat pump upstairs is a Carrier and has worked fine. So I was not afraid of the brand. I asked around for contractors that people had good experience with and let them bid their choice of equipment. My experience is if you ask tradespeople to put in your choice they will but if there is then an issue, they will remind you of who chose that equipment. The contractor with the best deal wanted to put in another Carrier.

I went with a 95% effecient condensing furnace and a 17 SEER AC, if I remember right. It is a pretty high end unit with a fancy programmble thermostat and a dual speed blower. It was a couple thousand more than the cheapest system. I had the additional money. I am hoping in addition to saving me a little on gas and electricity it will be better made and last longer. When it is using the lower speed blower it is VERY quiet. Another logic I used was I am getting fairly close to retirement. I have the money for the more expensive unit now but may appreciate the energy savings more when my income is potentially more limited.

Jim

[cabinetman]

No telling how old our system was when we bought this house. We replaced the system about 11 years ago. It's electric heat/cool 4 ton, split systreem, 16 SEER I think, Janitrol/Goodman. It's been a trouble free system per se. The problem is the return air (24"x24") is right next to the floor. With 2 German Shepherds and three cats, we are changing the filter about every 10 days. About twice a year, I clean out the drain pan, and blow out the condensate line.

We replaced the condensate pump once, as it has to pump uphill about 6ft, then horizontally about 12', and then the line drops to an outside french drain. The old system was working when we did this install, and the A/C guys took it (I guess they could sell it), and this one was about $3000.

.

[woodturner]

So far I have 1 contractor made me an offer and it includes about $7K for basic heat/AC combo installed or $14K for advanced hybrid.

Those prices seem very high, but prices do vary by area.

I replaced my furnace with a Lennox unit last year. It was $2500, would have been $3500 if I had replaced the AC as well. After rebates (fed and state), it was $200 net.

Carrier and Trane equipment were once considered "top of the line" but now seem to be overpriced and plagued by problems. Good brands include Rheem and Lennox. Be aware that there are only 5 or so manufacturer's, with multiple brand names, so often you can save money by buying their "off" brand or generic equipment.

To get feedback from the pros, try hvac-talk
http://hvac-talk.com/vbb/forumdisplay.php?f=1

[eezlock]

central heat and A/c

A suggestion here, check with consumer reports and see what they say about these new units.

You might want to invest in a gas package unit natural gas or propane for the heat, it would also have the a/c built in as well. That is what we have had for several years( had to make some repairs to a/c and heat sides of unit
over the years) but overall a good unit. I like the package unit better than a split system because all the working parts are in one location, nothing under the house but duct work, makes repairs easier.

I would NOT consider a heat pump unless it was to be used in south Florida.
Any other location farther north....too little heat, for too much cost!
I had one in a house I rented several years ago, learned to hate that thing
in just one winter, the system and the backup electric strip heaters in the duct work ran almost constantly in cold weather, and we stayed cold all winter long! Never again, for a heat pump!

[justaguy]

When we moved two years ago I replaced my Heat/AC and water heater units which were about 20 years old. I installed a 20 seer heat pump with a 98% gas furnace for backup heat, a steam humidifier, and a tankless hot water heater. I saw about the same price difference (7K) between a base system and my higher efficiency units. The tax and energy credits from the state and feds reduced the price difference by $2700.00. The equipment installed was American Standard / Trane.

Prior to installing the new equipment the averaged monthly electric bill was $250.00 and the natural gas bill was $125.00 per month. With the new equpment my monthly averaged electrical bill is $126 and natural gas is $62.00. Keep in mind that I also replaced all of my doors, windows and appliances with new high efficiency units as well.

My thinking was I can afford the equipment now and when I retire I want the utility bills as low as possible. Based on my new monthly utility bills I would do it again.

[justaguy]

I would NOT consider a heat pump unless it was to be used in south Florida.
Any other location farther north....too little heat, for too much cost!
I had one in a house I rented several years ago, learned to hate that thing
in just one winter, the system and the backup electric strip heaters in the duct work ran almost constantly in cold weather, and we stayed cold all winter long! Never again, for a heat pump!

I have a heat pump with a backup gas furnace here in VA which is a good combination. I have my heat pump set to provide heat when the outside temp is 45F or above. If the indoor temp drops 2 degrees or more below the thermostat setting, or if the heat pump can't reach the thermostat set temp in 10 minutes, or if the outside temp is below 45F the gas furnace is used.

For a combined AC/Heat system having the AC unit be a heat pump only added about $600 to the price 2 years ago for my system.

I do agree that no way I would have done a heat pump with electric backup heat.

[vaking]

Thanks guys, very informative.
In the past few days I did a lot of reading. I want to clarify few things. My house has 2 central air units. One is in the attic and covers the second floor, the other is in the crawlspace and covers first floor and semi-finished basement. This discussion is about the unit in crawlspace. Working in crawlplace is very uncomfortable, but replacing this unit will require fair amount of labor to be done there. I guess this contributes to the high cost of the project.
Both units that I currently have are Rheem. Once I started reading I realized that I may have additional factors to consider. I bought the house 15 years ago and people before me made a lot of changes when they first moved in (16 years before that, so 30 years ago). When they bought the house they had the money but they were impractical people and did not know much about houses. They were putting in high end equipment but were hiring contarctors that were doing sloppy work and taking owners for a ride. I have already seen evidence of this in several places and central air seems another example. The unit downstairs is 100KBTU and the upstairs unit is a little larger, probably 125 KBTU. The house has about 2500 square feet finished space. I undertsand that the house is old (1929) and insulation in walls is probably lacking but still I have hard time believing that it needs over 200KBTU of heat-generating equipment. Most likely the contractor 30 years ago simply convinced the owners that "bigger is better". Reading in the past few days suggested that units are oversized for the amount of heat needed and for the size of ducts that I have. The contractor I had so far simply estimated that unit I am replacing was 100KBTU with 80% EFAU and new unit will be over 95% so he proposed to put in 80KBTU high efiiciency unit. I am now thinking that any contractor I hire will need to do real calculations and come up with the correct unit size. Since I moved into the house I had been making gradual improvements throughout it increasing insulation. I replaced some doors, added new low-E storm windows, added insulation over that crawlspace. If the unit was oversized originally (as I think) by now it has become even more oversized.
Equipment that the contractor suggested pretty much matches what Justaguy described. High efficiency multi-stage gas furnace with variable speed fan motor, AC unit with SEER around 20 and a heat-pump. Equipment proposed was York but everything I read suggests that all manufacturers are competitive and the important choice is not the brand but the quality of installation. Every manufacturer has his network of installers and every installer typically works with one preferred brand. The guy I had was the York speacialist, Lennox is supposed to be next. My job supposedly is to chose the installer I like and let him install the brand he works with. Sounds easy enough, isn't it? I guess that was what people in my house did 30 years ago.

[LCHIEN]

whether or not high efficiency A/C and or heat will benefit you depends greatly upon the heating and cooling days in your area and how much electricity and heating fuel is expected to cost.

If you have to heat a lot of degrees and days then and heating fuels are expensive then a high efficiency heater will be of benefit. conversely if there are a lot of degree-days of cooling required in your area, and electricity is high then an efficient A/C will be of benefit. Obviously if you only use heat a few days a year in a tropical climate and it rarely approaches freezing then a high efficiency heater that seldom gets used will not be paying off for the extra thousands it may cost. Probably your heating - A/C guy in your area will be the best source of info if you trust him (not to try and oversell you).

[jackellis]

It may be too late for this but make sure you've sealed air leaks as best you can. Particularly in winter, insulation does you no good if cold air is entering through gaps in framing, around windows and doors, etc. If you have a fireplace, install doors and make sure it gets its combustion air from the outside, especially if you can't seal the air leaks.

Like some of the others who responded, we invested in energy efficiency while we were building so we would not have to worry as much about heating bills when we both stop working.

You may also want to consider installing a whole house fan for summer cooling instead of using the A/C.