Getting quotes on HVAC system for my own home

[imported_John Smith]

This is a new one on me, but I am going to start getting quotes on a new HVAC system for my primary residence. I have heard various opinions on manual J's, and such. For a true apples to apples comparison (or HVAC to HVAC comparison) what should I require?

My primary residence is an older home with a vertical combo AC/heating unit (Rheem, vintage 1979). My service tech said I should go with a horizontal system in the attic when I get bids, but I have a 4-12 pitch roof with manufactured rafters. I think it would be kind of hard to fit that type of system in the attic. I do plan to replace the heating system (natural gas) also.

I will only live in this home for another 5 to 10 years, at which point I will sell it.

[Markus Keller]

Hi John some points to consider.
For the amount of time you are going to stay in the house, spend the money on a good system.
- Going with a horizontal in the attic generally only makes sense if there is a need to do so. You need the basement space, duct runs, zoning, etc.
- Ducts in attic should be sealed and insulated. Additional costs such as pan & drainage, iso pads, access, service area with floor and lighting, possible hanging of unit, insulation issues if you have loose fill, , load distribution calc on your truss system, etc. all come into play. I would recommend against unless there is a reason to do so.
If you have an upflow unit in the basement, I'd say stick with it, you can run a trunkline into the attic for better air distribution, without a lot of the added expense.
- An experienced installer doesn't need to run a Manual J load calc if you have a typical house for the area. He's done your house a hundred times. Yes, it's a good idea, yes it is helpful but not a must for standard Res work. If you ask the guy if he is going to do one and he doesn't even know what it is, then get someone else.
- Get a 92%+ AFUE unit, Goodman, Rheem, York whatever is common in your area. I would stay away from proprietary units such as Amana or Lennox. Parts are harder to get and you have to be registered with them as an installer/tech to buy parts. (at least around here) You could consider a modulating unit. Feedback so far has been good and bad.
- Do you have newer ducts or old massive gravity feed ducts? Proper duct sizing and returns are key to a comfortable system. If you have duct issues, this is the time to deal with them.
- Getting bids that are closer to each other as far as Spec.'s will depend on what you tell the contractors you want. Put together a bid sheet. Unit, ductwork, air filter set-up, stat, etc.
- How big a unit or house are you looking at? Make sure a sufficient size return drop is installed. 120K + BTU usually require a return drop on both sides.
- Demand exterior combustion air
- AC - 16 SEER
- You can dramatically cut your utility bills and increase your comfort level with a new install. This will NOT happen just because you install a new 90+. Supply and return are key, this has a far greater impact on efficiency that people give credit.

[H.G. Watson, Sr.]

split sys Heat Pump with NG heat backup. Forget A/C.

[Jerry Peck]

My primary residence is an older home with a vertical combo AC/heating unit (Rheem, vintage 1979). My service tech said I should go with a horizontal system in the attic ...


Need missing information: Where is your current unit located? Will make a BIG difference on any recommendations.

[imported_John Smith]

Thanks Markus and HG. Basements are extremely rare in Houston homes. Slab on grade or pier and beam are kings. Mines a slab on grade. I thought Amana and Goodman were almost the same, just different names applied.

As far as a heat pump. They seemed to be popular in the early or mid 80s, but I hardly ever see them.

I only have one return air. It is located in a hallway adjacent to the living room. Downside is the noise when the unit kicks on. I dont know an easy way to install a vertical system in the home without using the same return air (the vertical system sets on top of the return air plenum.

[Markus Keller]

Sorry about that, I live in the land of basements. As far as I know Goodman is independently owned and not affiliated with Amana. I could be wrong though.
Yours sounds like a fairly typical install. If the unit is located in the closet, you can have your guy extend the return trunk into the attic and run a trunkline to several locations for return air. This will do several things for you.
- reduce overall noise level
- increase air circulation
- reduce cooling costs
Goodman makes a good unit, both on the Heat and AC sides. Cost for equipment is reasonable. Repair is easy and parts reasonably priced.

[Jim Luttrall]

John, Goodman bought Amana but I don't know if there are still differences in the product.
I put in a Goodman heat pump a few years ago and have no complaints.
When I had mine done, I got bids from two different companies and both wanted to up-size from the existing system by 25% to 50% which did not make sense to me since the system was performing well (just 25 years old.)
I went with an alternate route and replaced with a same size Goodman.
It may be different in your area but it seems around here they want to build in a fudge factor instead of accurately sizing the system.

I would not waste money on a high efficiency furnace since you are not in a heating climate, you'll wear the thing out before getting a ROI for the difference.
I would however spend extra for a higher SEER rating on the A/C or heat pump and try to get a variable speed unit to help with de-humidification.
An over sized system that shuts down before getting the moisture out of the house will leave the house like a meat locker, Cold and Clammy.

Doing a load calculation is just basic for selecting new equipment but you'll never know if they did unless you ask. Ask them how many BTU's for the Cooling Load and how many for the heating. I'm guessing you would need far less heating than cooling. Ask them what they used for the design temps for summer and winter. If they stammer, say "next please" since they did not run or do not understand the load calculation program they are using.

[Rick Hurst]

Most HVAC guys I know say they replace their own equipment with American Standard. American Standard I believe owns Tranne.

Goodman units I believe are a good unit, but most HVAC contractors talk trash about them. They are probably the most seen unit in the Dallas area besides a Trane or a Carrier. Personally my home came with the Amana units when we bought it several years ago.

My opinion is that most of the units are on about the same standard. It is the installer that you should place the most trust into doing the job right.

rick

[Jerry Peck]

I just inspected some stainless steel Amana units, made by Goodman, with the Goodman name on the installation instructions but with an Amana warranty card, supposed to be guaranteed for 12 years (against rusting out). The condenser unit housing sides were stainless steel, the bottom was some type of plastic (used on many different units) and the top was a similar material.

Only problem I saw, though, was that all the units around it which were old had the aluminum coil fins corroding off ... and that nice super duper stainless steel Amana had aluminum coil fins ... :rolleyes: ... so much for the extra money.

The condenser units on the condos right along the ocean last maybe 4 years ... if the owner is lucky.

The front panel of the air handler unit was also stainless steel, but the rest of the air handler unit cabinet was not.

Relatively mid-high dollar 18.6 SEER system.

[imported_John Smith]

Current unit (air handler) is actually located in a "closet" in the garage. It sits up ~2-1/2' above a ledge where the washer and dryer are installed. The 2-1/2' is where the unit pulls return air in from the front hallway. The current unit is all enclosed, you cant even see the evaporator coil.

One thing about Goodman, they are located in Houston. I know an electrical engineer that used to work for them.

My AC guy says they are as good as anything else. I see a lot of Tranes in new construction.

[Jerry Peck]

Current unit (air handler) is actually located in a "closet" in the garage. It sits up ~2-1/2' above a ledge where the washer and dryer are installed. The 2-1/2' is where the unit pulls return air in from the front hallway.


To relocate that unit to the attic would be a mistake in my opinion.

Not only would you need A LOT of attic space to place the unit in for proper location and service access, but to re-route the supply and return ducts to where they need to be, and to do so without interfering with the service access to and in front of the unit.

I would replace it with a new unit where it is, and if the unit is open to the garage (you said it was in a "closet", so I'm not sure if that means an actual closet or just something surrounding the AHU) I would enclose it in an actual closet, walled off, taped and sealed, and make the closet face the hallway, finishing it off with a door to the hallway to provide access to the unit.

That would get the unit 'out of the garage', allow re-use of the supply and return ducts/plenums, and avoid the pitfalls of locating the unit in the attic - see below:
- M1305.1.3 Appliances in attics. Attics containing appliances requiring access shall have with an opening and a clear and unobstructed passageway large enough to allow removal of the largest appliance, but not less than 30 inches (762 mm) high and 22 inches (559 mm) wide and not more than 20 feet (6096 mm) long when measured along the centerline of the passageway from the opening to the appliance. The passageway shall have continuous solid flooring in accordance with Chapter 5 not less than 24 inches (610 mm) wide. A level service space at least 30 inches (762 mm) deep and 30 inches (762 mm) wide shall be present along all sides of the appliance where access is required. The clear access opening dimensions shall be a minimum of 20 inches by 30 inches (508 mm) by 762 mm), where such dimensions are large enough to allow removal of the largest appliance.
- - Exceptions:
- - - 1. The passageway and level service space are not required where the appliance can be serviced and removed through the required opening.

- - - 2. Where the passageway is unobstructed and not less than 6 feet (1829 mm) high and 22 inches (559 mm) wide for its entire length, the passageway shall be not more than 50 feet (15 250 mm) long.
- - M1305.1.3.1 Electrical requirements. A luminaire controlled by a switch located at the required passageway opening and a receptacle outlet shall be installed at or near the appliance location in accordance with Chapter 38.

[Scott Patterson]

I just inspected some stainless steel Amana units, made by Goodman, with the Goodman name on the installation instructions but with an Amana warranty card, supposed to be guaranteed for 12 years (against rusting out). The condenser unit housing sides were stainless steel, the bottom was some type of plastic (used on many different units) and the top was a similar material.

Only problem I saw, though, was that all the units around it which were old had the aluminum coil fins corroding off ... and that nice super duper stainless steel Amana had aluminum coil fins ... :rolleyes: ... so much for the extra money.

The condenser units on the condos right along the ocean last maybe 4 years ... if the owner is lucky.

The front panel of the air handler unit was also stainless steel, but the rest of the air handler unit cabinet was not.

Relatively mid-high dollar 18.6 SEER system.

Goodman has a plant in Fayetteville, TN where they make those stainless steel units. In their lobby they have a unit that has been running 24/7 for 8 years without any maintenance and when I was in the plant about 6 months ago it was going strong.

[David Bell]

I have seen Goodman units around since the early 80s. They came on the scene here in the east as a low priced alternative that supply houses could offer. Trane and American Standard are the exact same unit. Carrier home products and Temp-Star are made by the same Co. As you say that you are not planning to stay in the home long term I would use the existing ductwork, install a 16 SEER heat pump with electric back-up, and collect up to $1500 in tax savings. As far as brand names are concerned, most manufacturers are useing copeland scroll compressers, the difference lies in coil design and warranty. The one item I would try to upgrade would be the noisy return. Speak to a couple contractors at least and pick thier brain for ideas on reducing the noise.

[Jerry Peck]

Goodman has a plant in Fayetteville, TN where they make those stainless steel units. In their lobby they have a unit that has been running 24/7 for 8 years without any maintenance and when I was in the plant about 6 months ago it was going strong.

Yeah, but ... how long will it last in a salt spray environment like setting along the beach?

[Scott Patterson]

Yeah, but ... how long will it last in a salt spray environment like setting along the beach?

Who know! How long does anything last at the beach? My guess is about 20% longer than a non stainless unit.

[Markus Keller]

The beach sounds the same as high humidity basements. Whenever I'd put a unit in a damp basement I knew I would see that unit every winter for a service call. After only a few years the unit would look 20 years old. Always told people to deal with the moisture problems. Some did, some didn't. I guess they figured it was easier to pay me a couple hundred every winter than spend thousands fixing their basement moisture issues.
Goodman has always gotten a bad rap by guys who don't use them. Back when they were marketing under the 'Janitrol' name, guys would call them junkatrol.

[Matt Fellman]

I went with a Goodman when I replaced my unit last year. The cost savings was pretty substantial over the other brands and so far it seems just fine.

One piece of advice I'd give you is to get the exact model number of what the installer plans to put in and check it through the appropriate places if you're looking to get rebates.

In Oregon there were 3 rebates (2 state and 1 federal) and I lost out on one because the motor didn't qualify as "electronically efficient". It was only for $100 so not a huge deal but I found the process of "qualifying" wasn't as cut and dry as I expected. Basically, each agency that gives rebates has a huge list of model numbers and you have to check the list to see if your unit is on it.

[Jerry Peck]

The beach sounds the same as high humidity basements.


I guess they would be the same if the basements had salt mist being sprayed into them. Salt really does speed up corrosion considerably. ;)

[Trent Tarter]

I would install a heat pump system if you do not currently have gas to the property. If you have gas I would install a 90+ gas furnace with a heat pump unit. As far as brand goes I would go with the lower costs brands such as Goodman. If you are going to be selling the house in a few years I would not spend the extra money on a name brand system. A higher efficiency system and a good installation will be your best return on investment. Take a look at any available rebates or incentives that may be available from you local utility providers or the government. Many times a more efficient system will cost you less after the rebates. I have installed several Goodman systems and have not had any problems with them. In my opinion they make good affordable equipment.

Also if the home has existing duct work try to utilize as much of it as you can to reduce installation costs. Attic installations will typically cost less as the duct work is easier and quicker to install.

[Philip Ngai]

I would be wary of moving your evaporator to the attic in a location like Huston.
I can supply some references if anyone is interested in the reasons.