I got some more information on the new air conditioning choices I discussed at length in Two Bids a few days ago.
I finally called the company A representative back. Here are my questions and her answers (summarized--she talked to me for an hour).
1) Question: You recommended a 2.5-ton AC, and another company recommended a 2-ton AC. Do your calculations show us being on the border between the two?
Answer: She will e-mail me the calculation but it's all very scientific and there's only one right answer and no one could have come up with an answer of 2-tons unless they were just guessing, blah blah blah. They always send their calculations to someone else who double-checks the math and stuff.
Her e-mail says that her calculation shows I need 30,400 Btu's, and since 1 ton = 12,000 Btu's, that's not borderline. She said that if there were no humidity at all, then we could get by with 24,320 Btu's.
Conclusion: Rats. It does seem like Company B was just eye-balling it, and I have read everywhere that the calculation Company A is doing is the best way to figure this out. I think our 2-ton system works fine, or at least it did before we lost our shade tree and that should be simulated with solar window screens, but R. doesn't think our current system works fine. Maybe the right sized system will work even more fine.
2) Question: The other company said the insulation has not compacted and is still R-30.
Answer: That's true. But as soon as the guys install all the new ducts required for the new sized AC, the insulation will become compacted, so they will want to add more.
Conclusion: This answer makes sense to me and supports both companies' claims. Don't ask me how they know where to step when all the boards are covered by insulation.
3) Question: The air conditioners you recommended are variable speed but single stage. What does this all mean? [A friend recently got the two-stage kind, which he highly recommends. It runs less hard when not needed (and until things cool off a bit) and in that phase it's so quiet they can't even hear it.]
Answer: There is no two-stage AC at the 2.5-ton size. The best choice would be one at the 3-ton size which acts as a 2.1-ton AC during the first stage and ramps up to a 3-ton AC during the second stage. It costs $1000 more than the more expensive one she recommended, so she didn't think it was worth bringing up.
There's no choice about the variable speed. We need to have the slower speed available to keep down humidity.
Conclusion: Her explanation sounds reasonable to me. Also, I got the specific model number from Company B, and their recommendation is also for a variable-speed 1-stage AC.
4) Air filters
a) Question - The more expensive air filter option has a filter that can be vacuumed every six months. Is this made out of something different than regular filters, which I've heard are not supposed to be vacuumed?
Answer - It's not actually an air filter. It's an electric cleaner. It traps particles based on electrical charge attraction, but doesn't block air flow. It's made of metal. When you open it up, the dust falls and is easy to vacuum. It is recommended that you can either wash or vacuum, but washing adds water to the equation which encourages mildew, so around here they only recommend vacuuming.
b) Question - The other air cleaner requires a five-inch thick filter. Is this hard to find?
Answer - You can get this from A or from their distributor at Metric and 183. The filters cost $55 each and last for six months.
Conclusion: I like the idea of never buying filters again. It costs $950 for the fancy one, so it won't pay for itself in filter savings compared to a regular filter system at all. It costs $350 for the cheaper one, so with a difference of $600 and a filter cost of $55 per 6 months, the expensive one would pay for itself over the medium one in 5.5 years. We should pick either the filter it comes with or the super fancy one.
5) Question: What payment plans do you have?
Answer: a) Six months no payment no interest. b) If I apply for credit with Home Depot, they can get me 12 months with no payment and no interest. c) They take VISA and MasterCard. d) A cash discount?
Uh, they probably could give us at least the fee they would have to pay on one of the other methods.
6) Question: If we are near the border between a 2- and 2.5-ton AC, is there something we can change in the house to make it require a 2-ton AC?
Answer: It would only be about $300 bucks cheaper [plus $600 for the ductwork]. Any difference in price between my two estimates is probably based on the brand of AC rather than the size of AC. [Rats!]
Then she went on about how Trane is better than Lennox. First of all, Trane is top of the line whereas Lennox, RUUD, and Rheem or second-tier brands. I should ask B what brand of evaporator coil they would be using. Until recently anyway, they weren't using Lennox but ADP, which is bottom-of-the-line. The metal parts rust out but they give you a higher SEER rating.
Also, with Trane, they never mix copper and aluminum. They always use just aluminum. When you have copper touching aluminum, and a dog pees on it or too much of our acid rain falls on it, then you can get the
aluminum deteriorating away from the copper. Then there goes the efficiency. This applies to the coils (aluminum or copper) and fins (aluminum) on the outside unit and to different parts of the evaporator coil inside as well.
Also, Trane's warranty is by the manufacturer, whereas Lennox's warranty is by service companies. In the 1990s, when service companies failed, a lot of people lost their warranties. [Of course Trane could also go out of business during the useful life of my new AC, though it is unlikely.]
Conclusion: Copper/aluminum connections are indeed a bad idea. I read this, though: "If you[r] system is typical of most cooling systems, there is likely to be rubber or another non conductive material connecting the aluminum heat exchanger to the copper parts." R. says when some cars were built with steel bodies but aluminum hoods, doors, etc., they corroded more quickly than all-one-metal cars, even though they were separated by layers of paint and whatnot.
Either way, neither dog pee nor acid rain is likely to get into the evaporator coil inside.
If there's only a $300 difference between the 2.5 and 2.0-ton Trane ACs, then the question may really be whether we want a Trane over a Lennox. R. has heard that the Trane is slightly better. I don't know about this copper/aluminum interface question. Our current AC still works, and we're replacing it anyway.
Company B
1) Question: So I had called B to ask for a model number and he left a message while I was on the phone with A. I looked up the specs on this model.
Answer: Company B says they are offering an AC with a SEER of 15.5, but the specs for the model he gave me say it has a SEER of up to 14.5. Company A says they are offering an AC with a SEER of 15, but its specs say it has a SEER of up to 16.25.
Conclusion: The Trane may have a higher efficiency after all (especially after years of acid rain).
2) Question: What brand of evaporator coil are they using?
Answer: Aspen. All they make are evaporator coils. They haven't used ADP in years.
Conclusion: I can't figure out how good Aspen is.
3) Question: How do Trane and Lennox compare?
Answer: They used to be a Trane dealer. Both are upper-line, but the Trane costs more. In addition, it was harder for them to get repair parts for Trane, so they dropped them. They've been using
Lennox for 15 years now.
Conclusion - Company A would have us believe that Trane never breaks. I find B's perspective more likely.
FINAL CONCLUSION: I still haven't decided. A may be of more value, but it also costs significantly more.
I finally called the company A representative back. Here are my questions and her answers (summarized--she talked to me for an hour).
1) Question: You recommended a 2.5-ton AC, and another company recommended a 2-ton AC. Do your calculations show us being on the border between the two?
Answer: She will e-mail me the calculation but it's all very scientific and there's only one right answer and no one could have come up with an answer of 2-tons unless they were just guessing, blah blah blah. They always send their calculations to someone else who double-checks the math and stuff.
Her e-mail says that her calculation shows I need 30,400 Btu's, and since 1 ton = 12,000 Btu's, that's not borderline. She said that if there were no humidity at all, then we could get by with 24,320 Btu's.
Conclusion: Rats. It does seem like Company B was just eye-balling it, and I have read everywhere that the calculation Company A is doing is the best way to figure this out. I think our 2-ton system works fine, or at least it did before we lost our shade tree and that should be simulated with solar window screens, but R. doesn't think our current system works fine. Maybe the right sized system will work even more fine.
2) Question: The other company said the insulation has not compacted and is still R-30.
Answer: That's true. But as soon as the guys install all the new ducts required for the new sized AC, the insulation will become compacted, so they will want to add more.
Conclusion: This answer makes sense to me and supports both companies' claims. Don't ask me how they know where to step when all the boards are covered by insulation.
3) Question: The air conditioners you recommended are variable speed but single stage. What does this all mean? [A friend recently got the two-stage kind, which he highly recommends. It runs less hard when not needed (and until things cool off a bit) and in that phase it's so quiet they can't even hear it.]
Answer: There is no two-stage AC at the 2.5-ton size. The best choice would be one at the 3-ton size which acts as a 2.1-ton AC during the first stage and ramps up to a 3-ton AC during the second stage. It costs $1000 more than the more expensive one she recommended, so she didn't think it was worth bringing up.
There's no choice about the variable speed. We need to have the slower speed available to keep down humidity.
Conclusion: Her explanation sounds reasonable to me. Also, I got the specific model number from Company B, and their recommendation is also for a variable-speed 1-stage AC.
4) Air filters
a) Question - The more expensive air filter option has a filter that can be vacuumed every six months. Is this made out of something different than regular filters, which I've heard are not supposed to be vacuumed?
Answer - It's not actually an air filter. It's an electric cleaner. It traps particles based on electrical charge attraction, but doesn't block air flow. It's made of metal. When you open it up, the dust falls and is easy to vacuum. It is recommended that you can either wash or vacuum, but washing adds water to the equation which encourages mildew, so around here they only recommend vacuuming.
b) Question - The other air cleaner requires a five-inch thick filter. Is this hard to find?
Answer - You can get this from A or from their distributor at Metric and 183. The filters cost $55 each and last for six months.
Conclusion: I like the idea of never buying filters again. It costs $950 for the fancy one, so it won't pay for itself in filter savings compared to a regular filter system at all. It costs $350 for the cheaper one, so with a difference of $600 and a filter cost of $55 per 6 months, the expensive one would pay for itself over the medium one in 5.5 years. We should pick either the filter it comes with or the super fancy one.
5) Question: What payment plans do you have?
Answer: a) Six months no payment no interest. b) If I apply for credit with Home Depot, they can get me 12 months with no payment and no interest. c) They take VISA and MasterCard. d) A cash discount?
Uh, they probably could give us at least the fee they would have to pay on one of the other methods.
6) Question: If we are near the border between a 2- and 2.5-ton AC, is there something we can change in the house to make it require a 2-ton AC?
Answer: It would only be about $300 bucks cheaper [plus $600 for the ductwork]. Any difference in price between my two estimates is probably based on the brand of AC rather than the size of AC. [Rats!]
Then she went on about how Trane is better than Lennox. First of all, Trane is top of the line whereas Lennox, RUUD, and Rheem or second-tier brands. I should ask B what brand of evaporator coil they would be using. Until recently anyway, they weren't using Lennox but ADP, which is bottom-of-the-line. The metal parts rust out but they give you a higher SEER rating.
Also, with Trane, they never mix copper and aluminum. They always use just aluminum. When you have copper touching aluminum, and a dog pees on it or too much of our acid rain falls on it, then you can get the
aluminum deteriorating away from the copper. Then there goes the efficiency. This applies to the coils (aluminum or copper) and fins (aluminum) on the outside unit and to different parts of the evaporator coil inside as well.
Also, Trane's warranty is by the manufacturer, whereas Lennox's warranty is by service companies. In the 1990s, when service companies failed, a lot of people lost their warranties. [Of course Trane could also go out of business during the useful life of my new AC, though it is unlikely.]
Conclusion: Copper/aluminum connections are indeed a bad idea. I read this, though: "If you[r] system is typical of most cooling systems, there is likely to be rubber or another non conductive material connecting the aluminum heat exchanger to the copper parts." R. says when some cars were built with steel bodies but aluminum hoods, doors, etc., they corroded more quickly than all-one-metal cars, even though they were separated by layers of paint and whatnot.
Either way, neither dog pee nor acid rain is likely to get into the evaporator coil inside.
If there's only a $300 difference between the 2.5 and 2.0-ton Trane ACs, then the question may really be whether we want a Trane over a Lennox. R. has heard that the Trane is slightly better. I don't know about this copper/aluminum interface question. Our current AC still works, and we're replacing it anyway.
Company B
1) Question: So I had called B to ask for a model number and he left a message while I was on the phone with A. I looked up the specs on this model.
Answer: Company B says they are offering an AC with a SEER of 15.5, but the specs for the model he gave me say it has a SEER of up to 14.5. Company A says they are offering an AC with a SEER of 15, but its specs say it has a SEER of up to 16.25.
Conclusion: The Trane may have a higher efficiency after all (especially after years of acid rain).
2) Question: What brand of evaporator coil are they using?
Answer: Aspen. All they make are evaporator coils. They haven't used ADP in years.
Conclusion: I can't figure out how good Aspen is.
3) Question: How do Trane and Lennox compare?
Answer: They used to be a Trane dealer. Both are upper-line, but the Trane costs more. In addition, it was harder for them to get repair parts for Trane, so they dropped them. They've been using
Lennox for 15 years now.
Conclusion - Company A would have us believe that Trane never breaks. I find B's perspective more likely.
FINAL CONCLUSION: I still haven't decided. A may be of more value, but it also costs significantly more.