My 70 yo mother lives in the D.C. area and I'm on the other side of the country. It's hot as hell, the A/C is completely dead and needs to be replaced (vintage 1974, was on its last legs with leaks for years, now the compressor keeps killing capacitors and is completely dead).

She asked me to help her decide which HVAC proposal to choose and I need your sage advice. (I did some research on here but, in the limited time she has, I'm not conversant enough to get fully educated on this stuff.)

Here are the facts: Single family detached home with 2 stories and a basement, aprox. 3200 sq. ft. Built 1974 with a single furnace and A/C for the whole house. A/C is vintage 1974, gas furnace was replaced in 1984. Brick exterior on 50% and wood-type clapboard on the rest. Single pane wood windows with plexi storm windows. Very uneven air flow in the current system to different parts of the house--points close to the blower get decent heat/cool, rooms on the 2nd story of the opposite side barely get a dribble.

She has proposals from three contractors, some for replacement just of the A/C and some with an option to also replace the gas furnace. Here they are:

Proposal #1A $5149.00
5 Ton American Standard, 13 Seer, 4A7A3036A1000A and 4TXCD061BC3HCA.
Warranty: 5yrs parts, 2 yrs Labor, 10 yrs Compressor
(no indication who is providing the warranty.)

Proposal #1B. $7,945.00
Same contractor, A/C, and warranty as #1A, but replace furnace with American Standard AUD1D120A9601A, 80% AFUE, 120,000 BTU

Proposal #2A. $5,700
5 Ton American Standard, 4A7A3036A1000A, 13 Seer (no mention of the model for the coil other than "5 Ton Hi Efficiency Coil").
Warranty: 1yr parts and labor with the contractor, 5 yr limited parts warranty from the manufacturer, 10 yr extended parts warranty on compressor and outdoor coils, 20 yr extended parts warranty on "Heat Exchanger"

Proposal #2B $9,500
Same contractor, A/C, and warranty as #2A, but with new furnace, American Standard AUD140R9V5K, 80% AFUE, "2 Stage Variable Speed Furnace"

Proposal #3A $6,693 (Contractor thru Costco program)
Lennox Merit Series 13ACX A/C up to Seer 13 Model 13ACX-048
Lennox Merit Series ML180 Gas Furnace, 80% AFUE, Model ML180UH135.
A/C Warranty: 5yr Parts, 1yr Labor, "Compressor 5 Years"; if owner registers with Lennox within 90 days, the warranty is extended to "10 years full parts and & compressor".

Furnace Warranty: 5yr Parts, 1yr Labor, "Heat Exchanger 20 Years"; if owner registers with Lennox within 90 days, the warranty is extended to "10 years full parts"

I asked my mother whether anyone did calculations and she said "no, no one did." In fact, she asked one contractor whether he was going to do calculations or just rely on the existing units, and he assured her that calculations were not necessary.

I expect my mother will remain in the home indefinitely. She's been there since 1974 and I don't see her moving within 10 years; she's in great health. She doesn't like to run the A/C hard because she doesn't like it "too cold" and her electric bills are enormous when she does run it (I presume lots of that is from an inefficient, old system).

It's hot and humid this time of year in MD/D.C. My mother is 70 years old and her significant other is an 87 year old WWII Navy veteran. They need to get this contracted ASAP because this weather just isn't good for them at their age.

Any help you can provide would be greatly appreciated. I'll be traveling on and off for the next week so I apologize in advance if I don't get back to any questions within hours. I will be checking back every time I can, though. Apologies if I included too much info but I tried to anticipate questions I saw in past threads.

Thanks!

I think since the gas furnace is nearly 30 years old it should be replaced. You should get highest efficiency single stage upgrade in my opinion which is a 15 seer unit for your A/C. In your climate a heatpump may be able to provide the majority of heating with the gas furnace only helping during the extra cold weather (below 30). This upgrade shouldn't cost a fortune ($500 or so). Although your mother being older might night like the cooler air of the heatpump they do provide evenly heated rooms.

I would also advise against the builders grade outdoor units. These builders grade models are louder and don't have as nice of a cabinet. An upgraded model over the 13acx on quote 3a should only cost $200 more.

You should have the contractor look into duct issues is things aren't being heated correctly.

Don't oversize. I'm not sure you really need 5 tons.

Several questions.

1. Size of home
2. Size of Existing AC condenser to be replaced
3. Size of existing furnace along with blower rating size
4. Any existing problems/issues of old AC cooling adequately?

From your post, the ductwork system in this home needs a thorough inspection. The issue of poor airflow to upstairs needs to be investigated for suggestions to improve.

The furnace is about 27 yrs old, probably about 70-80% efficient. I would think about replacing. I notice dealers are all quoting 80% eff furnaces. The question is why? If there are no legitimate reason, I would want a two stg var speed model 95%+ efficiency. Now would be the right time to consider this.

I would not have the low end Lennox for my mother.

If you decide to postpone the furnace update, my choice would be proposal #1A. I don't like the furnace selection in 1B. If you are interested, I'll be glad to make several AmStd furnace selections.

I do not recommend a Heat pump for older homes with questionable insulation properties and because your mother probably won't like it.

IMO

The contractors told her that the existing A/C is 5 tons. That's all I know about it other than it was installed in 1974 and its kaput.
She hates heat pumps with a passion. They have one at the beach in Delaware and they said it was freezing cold to them in the winter. There isn't any chance she could be convinced so lets scratch heatpumps off the list.

I would really appreciate better recommendation for the American Std furnace option. Any info on why its better would be helpful.

Lastly, she mentioned that the Costco/Lennox guy advised her that it was a lower end unit (as I'm talking to her about the comments above). He said he can quote her a better unit. Is there a consensus whether Am Std or Lennox is preferable in general? I saw in other threads that Am Std was usually listed as a top brand but didn't see Lennox mentioned as a top brand as often.

Accurate sizing of new HVAC is important both for comfort and operating cost. I would like you to verify exactly what you have size wise.

Ductwork needs to be inspected and problems of airflow to second floor should be addressed with recommendations to improve.

As far as furnaces, my first choice would be a full modulating furnace like AmStd XC95m or York/Luxaire with a high eff 15 SEER AC condenser.

Can you tell me about the size and design of home as well as insulation qualities?

I am opposed to Lennox as well as purchasing HVAC through a big box store like Costco.

Post back when time is available.

IMO

second choice would be a good 2-3 stg var speed furnace like AmStd's XV95 or Carrier 58MVC mdl.

IMO

I found next to nothing on the a/c. The data plates outside are gone. I could see where it was but there was just rivets. A single, long rectangular unit outside. Like I said, vintage 1974, from the builder.

According to my mother, the quoting contractors guessed that the system was 4 or 5 tons. I don't know anything about who said what.

Turns out the Lennox/Costco guy was the only one to quote an upgraded unit. He also quoted:

Option #3B. $9,185. Platinum Package. A/C XC17-048 and 2 stage gas furnace SL280UH135 with variable speed and I-Comfort Communicating Controller.

I'm having a hard time getting her to look at the Am Std quote because they didn't quote her an upgraded unit option and their basic units were only about $1,000 cheaper than the upgraded Lennox units. ($9,145 vs $7,945).

About the house, I tried to describe it above. Built 1974. 3200 sq ft. and two stories. Attached garage. Full sun exposure--the property is not shaded. Brick exterior with not a whole heck of a lot of insulation. (I remember my parents being mad that the builder gipped them on the insulation.) High quality house though, expensive neighborhood. Stick framed over a full basement. Attic with pitched shingle roof. Colonial. Original single pane wood windows with storms windows, maybe a tad drafty.
After being widowed with 4 kids in 1978, she never had the money to remodel anything and everything is pretty much 1974. Anything else you want to know about the house, please ask. This is all I could think of.

I've seen posts here and there about how it does not cost that much extra to bump up to a higher grade model within the same brand. The upgrade in the Lennox quote to better ac and furnace increased the quote by a few thousand dollars. Should the upgrade to the better Am Std units you recommended also cost a few thousand more? I'm trying to get an idea so I can follow up with that contractor (#1) and have a sense whether he's giving a good price or not for the upgraded units. (BTW, he sent my mother an email and told her that he would "up her warranty to 10 years" if that would get the deal done. Not sure of the specifics other than that.)

Thanks much.

Some won't do it, others who are competitive will. Ofcourse they will confirm or deny those prices after examining the place where the install is occuring.

Just a couple of observations.

One of the least expensive and best bang for buck a homeowner can do both for comfort and operating costs is check and upgrade home's insulation properties. I would recommend that underfloor insulation for main floor be checked as well as attic insulation.

A telephone call for an HVAC quote is a waste of time. Not certain which is worse, the homeowner making the call or a questionable dealer willing to provide an answer.

It is foolish for a dealer like the Lennox dealer to quote an 80% eff furnace. What in the world are they thinking?

Current furnace is obviously grossly oversized which was quite typical for the time. Oil and nat gas were cheap. Who cared? More is not better. As stated before and can't be emphasized enough, ductwork in this house needs a thorough inspection both trunk lines and supplies/returns and in particular the air flow issues to top floor.

I like AmStd much better than Lennox and would never recommend purchasing HVAC through a big box store.

Let me know if I can help further.

IMO