A very nice system. However, I would drop back to the 60 KBTU furnace model. Insist on load calc to confirm. As I recall, the 80 K model in the quote would be larger than what you have.

IMO

Thanks for reply. I have a 75k btu furnace at 80% efficiency which is 60k btu. The lower 60k btu at 80% eff is 47k btu, so much lower than what currently have.

I'll see what the next independent havoc place says about smaller furnace.

I suspect you are oversized on your existing furnace so the smaller furnace would be appropriate for your moderate winter climate.

Can't understand why dealers want to oversize.

IMO

I would want the 048 coil that gets you to 14 SEER and 12 EER.

IMO

Tiger,

Do you think that the lack of wall/floor insulation makes a big difference in the recommendation to oversize?

Also, what about claim that R22 is colder than R-410A, so you need a bigger a/c compressor?

These were two reasons that I got from installers.

I revised my equipment requirements as you suggested and I'm having installer review my choices:

1. American Standard 3 Ton Condenser
Allegiance 13 / Gold SI / Up to 14.5 SEER depending on coil
Model = 4A7A3036

2. American Standard Gas Furnace 80%
Silver XI / Freedom 80
High Efficiency Blower. Single Stage. 3 Ton Blower; 47K BTU
Model = AUD1B060A9H31B

3. American Standard Evaporator Coil
Model = 4TXCB048BC3HCA (14 SEER with this compressor?)

4. American Standard PerfectFit Air Cleaner 5" Filter (optionaldepending on price)

5. New lineset = want new lines since replacing refrigerant from R22 to R-410A

6. Thermostat American Standard 803 or Honeywell 8321

7. Use existing flexible insulated ducts if they are working well.

8. Use existing registers/vents/returns if appropriate.

Personal opinion: the R22 vs R410 is bunk. 3 tons is 3 tons of cooling regardless of the refrigerant used.

Exactly my sentiments...

Any dealer that spouts that nonsense on R22 VS R-410 should be shown the door.

IMO

Thanks. This particular dealer is out for various reasons like highest bid without any details and using the 25-year experience card to explain why I needed what he recommended.

Today, I spoke with a 3rd independent dealer over the phone about the 3 ton system that I spec'ed out with Tiger's help. Again, this dealer is sticking to the 400 sqft per ton rule of thumb for a/c and is recommending a 3.5 or 4 ton system.

I told him that unless he does a Manual J calculation, I'm going with a 3-ton system. He's pricing out my selections and will e-mail me a quote.

I have another question. Isn't the 803 thermostat overkill for me? I have a single stage system with no humidifier and no dehumidifier. I only have 1 zone...the whole house. So, why would a 803 thermostat be good?

Ran my own load calculation using a free web site. I'm not sure that I entered everything correctly, but it looks right.

I don't have wall insulation, but entered information as if I had wall insulation because I'm going to install it soon.

I think this means 3-ton AC and 2-ton furnace?

By the way, removing the wall insulation (which I don't have yet, but plan to get) causes the cooling calculations to go from 36K BTU to 42K BTU and the heating calculations to go from 32.5K BTU to 36K BTU. So, my current 3.5 ton a/c is right, but my furnace is way oversized.

I did use a higher outside summer temperature of 95 instead of the average 89. I also used a colder winter temperature of 38 instead of the 40.

Also, I used the standard inside temperatures (75 and 70) even though I like 78 for summer and 68 for winter and I'm comfortable with those.

I used a free web site: http://loadcalc.net/

Here's the updated Manual J with no wall insulation. I slightly changed the window sizes to be more accurate and used 39 for winter outside temp.

The bottom line is that the R13 insulation in the walls for my 1430 sqft house reduces the load calculation by about 1/2 a ton on a/c and furnace. So, without wall insulation (but R25 attic insulation), my a/c is at 42K BTU (2.5 tons) and my furnace is at 36K BTU (3-tons).

Ham

I always like to congratulate homeowners who make the effort to perform a load calc. It is good information especially if you have a load calc to compare against the dealer.

A couple of things.

Trane/AmStd 803 stat will help you on humidity control in AC cooling. If humidity is not a concern for your climate, then forget about it and go for a quality stat like the 802 model or same HW VP 8320. Honeywell makes Trane stats, some are just rebranded, the high end mdls are proprietary.

I still would stick with the 3 ton AC condenser. Here is the sticky part though. You must have a three ton rated blower in your furnace for AC cooling. This is problematic because it is difficult to find a small BTU furnace with a 3 ton blower. I am not surprised at your load calc for heating.

I did a little research this morning and found a quality Rheem furnace with a 41 KBTU output and a three ton blower. It is a comparable model to the AmStd as it has the high eff x-13 blower. I am providing a link for your review. Still think the AmStd quoted would be fine. Certainly it is better than what you have and will save in operating costs.

What have dealers said about new lineset?

I do encourage you to consider a whole house pleated filter media cabinet. As long as you have good accessibility, changeout is easy and these filters last up to one year before filter needs replacing. I have Trane's Prerfect FIt media filter.

IMO

Here is a link that might be useful: Rheem Furnace

Thanks for the advice.

On the Trane/AmStd 803 stat, it looks like the price difference between the 802 and the 803 should only be about $20, so I'll just get the 803 since it offers additional functionality.

I'm good with using the AmStd Freedom 80 furnace at an effective 47K BTU.

Dealers are saying the lineset can be flushed, but I've asked to replace it. I rather not worry about mixing R-22 with R-410A. It looks easily accessible going through attic to the outside wall.

Make no mistake. Lineset whether new or reused and flushed must be to the correct size from condenser manufacturer spec.

Close does not count.

IMO

I wasn't very successful in getting detailed American Std quotes. I got one that I didn't like for $9425.

I was able to get a quote for a well-matched Trane system for a lower price, but still too high for my taste.

* Trane XR13 Condenser, 3-Ton. Model = 4TTR3036D
* Trane XT80 Gas Furnace 80% AFUE, 60K BTU, 3-Ton High Efficiency Motor. Model = TDD1B060A9H31B
* Trane Coil 4TXCB048BC3HCA
* Trane Thermostat Model = XL803 (with humidity control)

ARI Ref = 3790536
Condenser = 4TTR3036D1
Coil = 4TXCB048BC3
Gas Furnace = XT80 TDD1B060A9H3
EER = 12.00
SEER = 14.00

This the price for the equipment and installation. No duct work, flush and reuse existing lineset. No rebates.

You doing yourself a disservice by having 3 active threads running simultaneously.

IMO

They are 3 different manufacturers and I wanted to put some closure on each thread about what I found to be a well matched system with ARI reference numbers.

I was hoping the information would help someone else searching old posts on 3-ton systems.

I might start a new thread when I'm ready to ask about which of my final 3 a/c systems is a better buy based on equipment and price.

But it gets confusing to follow.

With the lineset, it's not so much R22 mixing with R410. The flushing with nitrogen(?) should take care of the gas component. The problem (as I see it) is debris and oil. The oil used by the two systems is incompatible.

Thanks for the explanation on the lineset. One dealer said that it costs about $100 to flush, but $200 to replace my existing lineset. Not sure if the price is accurate, but he said it was worth replacing.

It just sounds like it's safer to replace the lineset to avoid any potential issues.

I do understand that the lineset has to be the proper size as specified by the equipment manufacturer.

If sized correctly, $200 is a fair price.

I got the quote for $8000 for the Trane system that I want:

* Trane XR13 Condenser, 3-Ton. Model = 4TTR3036D
* Trane XT80 Gas Furnace 80% AFUE, 60K BTU, 3-Ton High Efficiency Motor. Model = TDD1B060A9H31B
* Trane Coil 4TXCB048BC3HCA
* Trane Thermostat Model = XL803 (with humidity control)

ARI Ref = 3790536
Condenser = 4TTR3036D1
Coil = 4TXCB048BC3
Gas Furnace = XT80 TDD1B060A9H3
EER = 12.00
SEER = 14.00

This includes flushing and re-using lineset, re-using ducts and registers, installation, no rebates, permits, and testing refrigerant levels as part of permit.