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ming001

Trying to determine best option for new HVAC

ming001
12 years ago

This is an unfamiliar territory for me but based on others posts lets hope I get all the information out that would help you help me....

I have a 1400 sq ft single floor house in Atlanta. It's 100+ years old and I've been working at getting it to be less leaky but I still need windows in some rooms repaired as well as completely residing and insulating the entire house. The house was a duplex before I bought it and there are 2 HVAC units (left and right) that were here before I moved in. One of the HVAC contractors said they were built in 1998 but I thought they were older than that when I moved in early 2000.

I am inclined to believe the one company that told me that I don't really need 2 units in a house this size where it's mostly all open. The bedroom with bath and office all have doors. Therefore I'm only providing their options. They are suggesting to rip everything out including all the duct work, relocating a furnace centrally under the house and rerunning all duct. There would be a few changes in vents as well but that was all included in the cost.

I'm at a loss in terms of just about everything: is 16 SEER too much for house this size? Would bumping from an 80% to a 95% system be worthwhile? And is a heat pump a wise choice.

Here are the numbers they've given me (5 options)

Carrier 80% Infinity Variable Speed Gas Furnace

Model# 58CVA090-1-16

ADP R410A Coil

Model# C36H175D459W

Carrier 16 seer 3 ton Infinity Air Conditioner

Model # 24ANB636A003

Total price for this installation including tax and permits would be $9843 after rebates

Carrier 80% Infinity Variable Speed Gas Furnace

Model# 58CVA070-1-12

ADP R410A Coil

Model# C36H142D439W

Carrier 16 seer 3 ton Infinity Heat Pump

Model # 24HNB636A003

Total price for this installation including tax and permits would be $10367 after rebates

Carrier 80% Multi-Speed Gas Furnace

Model# 58PHA070-1-16

ADP R410A Coil

Model# C36H175D459W

Carrier 16 seer 3 ton Air Conditioner

Model # 24ACC636A003

Total price for this installation including tax and permits would be $8939 after rebates

Carrier 96% Infinity Variable Speed Gas Furnace

Model# 59TN6A080V17-14

ADP R410A Coil

Model# C36H175D459W

Carrier 16 seer 3 ton Infinity Air Conditioner

Model # 24ANB636A003

Total price for this installation including tax and permits would be $10867 after rebates

Carrier 95% Multi-Speed Gas Furnace

Model# 59TP5A080E17-16

ADP R410A Coil

Model# C36H175D459W

Carrier 16 seer 3 ton Air Conditioner

Model # 24ACC636A003

Total price for this installation including tax and permits would be $10,090 after rebates

Any suggestions or advice gladly taken!

Comments (16)

  • mike_home
    12 years ago

    There is no reason to be getting an ADP coil. Ask the contractor to quote the matching Carrier coil.

    What are your electric and gas rates? This will help determine if you should opt for the heat pump or not. What is your average low temperature in the winter? A 95% efficiency may have a long pay back in your climate.

  • neohioheatpump
    12 years ago

    Are the prices for one or 2 systems? Prices seem high.
    If your in atlanta I would have a heatpump and maybe an 80% furnace coupled with that. In a mild climate like yours a heatpump should do well most of the time.

  • ming001
    Original Author
    12 years ago

    Thanks for the responses!

    Mike, I'll ask about the Carrier coil. I'll have to find the rates but I don't see ATL as being mild so I've decided against the heat pump all together unless they have changed dramatically since I owned my house in south FL.

    Neo, that's for removing the 2 systems and installing one system centrally under the house with everything that goes along with it.

  • mike_home
    12 years ago

    The fourth option is the best equipment if you are not going to get a heat pump. If you have high humidity in your area, then I suggest you get a quote on a 2-stage AC. You should also get the Infinity controller to control the 2-stage equipment effeciently and provide the best comfort.

    The sizes of the equipment seem to be correct, but you want to make sure. Ask the contractor if he has done a load calcualtion. I also recommend getting a 4 inch media filter and the Carrier 10 year labor warranty.

  • tigerdunes
    12 years ago

    Ming

    No third party ADP coils. You want the best matching Carrier Tin plated coil.

    All the Infinity furnaces will require the Infinity control. Waste of your money buying an Infinity Furnace without the Infinity control.

    Not certain why but I would say all the furnace quotes are oversized with exception of quote #2. Either the 70 KBTU 80% or 60 KBTU 95%+ efficiency.

    How would you describe the insulation qualities of your 100+ yr old home? If poor and home is not tight, I would not recommend a heat pump
    even in a dual fuel application.

    What size is your current furnace and AC?

    How do you filter your return air?

    Post back.

    IMO

  • ming001
    Original Author
    12 years ago

    Tiger, thanks again. I will ask right now about the matching Carrier plated coil.

    I am not sure if the Infinity control is included. And to both you and Mike, I don't know what a 2-stage is but I'll ask him about that as well.

    My insulation sucks. At one point I'll have the house resided and properly insulated and take care of the original windows that remain.

    I know that currently one unit is a 2 ton and the other is a 1.5 ton. I think my return air is filtered at the furnace... at least that's where the filters are located :-)

  • ming001
    Original Author
    12 years ago

    Here's the response I got:

    here is not really a particular reason why. We usually go by the federal ARI lists as to what systems actually perform at. Some Carrier systems are paired with Carrier coils and some are paired with ADP coils. They are a little bit different design so they provide a different seer rating. The Infinity control is included in the overall price. Yes, we always refer to a load calculation on every home which is required by GA CODE. We actually use a couple of different web sites that provide us with all of the information that we need on every home that we visit.

    Any thoughts?

  • tigerdunes
    12 years ago

    I know that currently one unit is a 2 ton and the other is a 1.5 ton. I think my return air is filtered at the furnace... at least that's where the filters are located :-)

    Ming

    Have no idea what the above means when you refer to a 2 ton unit and a 1 1/2 ton unit. That is confusing to say the least. Pls recheck.

    You do not want an ADP coil, only a Carrier tin plated coil. Any dealer who says otherwise, then run don't walk away.

    What is your existing furnace size and efficiency?

    I would not recommend a HP in a home your age with mediocre to poor insulation qualities.

    For the kind of systems you were quoted, you should insist on a pleated filter media cabinet.

    Any rebates included? Those prices are very frisky.

    IMO

    Post back.

  • ming001
    Original Author
    12 years ago

    Tiger, those prices include the available rebates already applied to the total cost of a new system, new duct work etc.

    Currently I have a 1.5 and a 2.0 ton units from when the house was a duplex. That's why they'd rip everything out and replace with a single centrally located unit.

    I believe they are both 80% units since they are 15 years old and there was no extra $$ put into this house.

    I'll have to insist on a carrier coil then. I can only go by what he said about the Carrier vs. APD but I can go back to him

    What the heck is a pleated filter media cabinet??

    Not sure if this helps but the rest of the proposal options all included language similar to this:

    1. Remove existing furnaces and coils from crawlspace. Remove all existing supply and
    return ductwork. Remove existing 2 ton and 1.5 ton A/C�s and pads from outside.
    Haul off old equipment.
    2. Install Carrier 80% Infinity Variable Speed gas furnace horizontally in crawlspace.
    Install furnace in a central location of home. Run new 4" double wall flue to closest
    existing stack going to roof. Extend and reconnect existing gas and electrical. Install
    ADP 3 ton R410a evaporator coil along with new supply plenum. Install Honeywell
    media air cleaner along with new return plenum. Mastic seal all connections. Install
    all new supply and return ducts using R8 insulated flexible duct. Cut in new 6" supply
    ducts in dining room and in hall bathroom. Run new copper refrigerant lines to
    outdoor unit location. Install

  • mike_home
    12 years ago

    The pleated media filter cabinet is a box usually installed between the return duct and the furnace input. You should get a cabinet which will hold a 4 inch thick fitler. The filter material is pleated. The pleating increases the surface area which acts to reduce the air resistance. The 4 inch filters are more expensive than a 1 inch filter, but they perform better and last 3 - 4 times longer.

    Which system did you decide to get? The quotes are not that high considering the removal of two systems, and then relocating the new system in another location.

  • ming001
    Original Author
    12 years ago

    Thank you everyone! Mike, I will ask about the filters. I have lots of animals so a better filter can't hurt.

    I'm going to go with the first option I think. 80% variable speed (no heat pump).

    I think with all new duct work that's stretched tauter (it's droopy currently) and the new system I will be loving my micro climate.

  • Annie Deighnaugh
    12 years ago

    Go geothermal...the you'll get heating and cooling in one and save lots of energy too. Only one unit, easily maintained. And a lot more reliable than an air sourced heat pump.

  • tigerdunes
    12 years ago

    Ming

    The 2nd option is a better choice with Infinity AC condenser instead of the Heat pump. More is not better. Ask dealer for a load calc on heating.

    You do want at least two returns properly sized. All R8 insulation both supply and return trunk lines and runs.

    I would get the pleated media filter cabinet.

    IMO

  • weedmeister
    12 years ago

    FYI: SEER has nothing to do with the size of the house. It would be like asking, "Do I want a car that gets 20mpg or 30mph?" The size of the motor doesn't matter in this case.

    The higher the SEER, the higher the efficiency. Or, the less money spent on your power bill every month. Each single point of SEER increase should lower your bill by approximately %4.

  • ming001
    Original Author
    12 years ago

    Tiger, the second choice *is* the heat pump. I don't want to go with that so I think you mean the first choice (variable speed).

    I'm very grateful for the help and advice. You helped me weed through the options and I'm comfortable with my decision. Let's hope the new system keeps me (more) comfortable!