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appreciative
07-03-2005, 12:19 AM
Great web resource, thanks.

I just bought a new custom built home that had a great inspection today. I got a steal on it. The only problem is the builder placed 2 "builder quality" Furnaces in, Trane 80's, one in the attic one in basement for a 2 story 3300 ft house. The J load is rated for 1.5 tons each, 16, 923 BTU's. He hadn't installed the A/C yet but has an allowance for 2 Trane 10 Seer, 2 ton units. The house is in Colorado and is insulated very well. I was planning on installing better A/C's because of sound and effieciency, thinking Trane 14XLi's or 16XLi's. I know I have to replace the coils to do so. Should I just go ahead and bite the bullet and upgrade the new furnaces now? I plan to be in the house for 7 -10 years
(I think). Is it worth it? It is a substantial amount of money to do so.

Any help would be appreciated.

dorrmann
07-03-2005, 12:38 AM
Here in Colorado, I always recommend a 90%+ furnace. You'll save TONS on your gas bills. It will definately pay off. Where in Colorado are you?

appreciative
07-03-2005, 12:54 AM
Thanks for the reply dorrman. I'm in Westminster.

appreciative
07-03-2005, 01:32 AM
Don't know if I responded correctly. Just wanted to make sure I thanked you Dorrmann. BTW, I;m in Westminster

Irascible
07-03-2005, 01:46 AM
I'm lost. You want uber-high air conditioning efficiency in Colorado? I didn't know that was such a hot area. If the summers are real mild then it makes zero financial sense to go to all that trouble. Get a couple of ten SEER units and save the capital expenditure for something else.

As far as noise goes, you don't need such a high SEER unit to get a quiet unit. I'm not a Rheem dealer. But those that are claim their 10 SEER units are real quiet compared to most. And there are plenty of 12 SEER units that are pleasantly quiet.

FYI: You do NOT need to replace indoor coils to install a 14 or 16 SEER unit. The main thing you'd need to do is install a TXV on both coils so that the coils and air conditioners will work well together. SEER ratings have nothing to do with functionality. And if you did install a 14 or 16 SEER unit on your existing evaporator coils you would still get the quiet you want and higher efficiency than a 10 SEER. It wouldn't be delivering the SEER it's rated for. But so what? If your summers are mild, you won't live in that house long enough to recover the capital cost of new coils in energy savings on your utility bill.

Of course none of my comments speak to the potential savings of a 90+ furnace. If that entices you then be aware that contractors are wont to exaggerate their benefit. They use bogus formulas based on heating degree days to determine energy savings that often has nothing to do with reality. If you have past bills then figure out your winter gas heating usage and knock ten percent off. Don't use silly formulas.

appreciative
07-03-2005, 02:04 AM
Irascible, it's funny. After reading your response to other people at this site, I went to your web site and was so impressed that I sent an email to your personal address stating as much. I came back here only to find your response. You are an ethical businessman.

Thank you. I just thought the home builder was trying to be cheap. I should have known that given his attention to detail on everything else in the house that he wasn't trying to cut corners.

Thank you so much. BTW, are you from the BAy Area? I was born and raised in Saratoga.

Irascible
07-03-2005, 02:15 AM
Well... I wouldn't say the builder wasn't being cheap. I have no idea what he was thinking. Even the most excellent builders tend to get cheap on HVAC because home buyers are so focused on appearances. The builders give buyers what they want. But if I'm to assume that you have mild summers (Do you?) then financially speaking ten SEER is absolutely the most logical choice.

Whatever you get, just make sure you have TXVs. TXVs will make high SEER condensers work nicely with older evaporator coils. And if you have a lot of low load situations, TXVs are excellent for that as well. On the other hand, if you get ten SEER units and only run the air conditioner 12 days per year on the hottest days then even TXVs are optional IMO.

appreciative
07-03-2005, 02:32 AM
Actually, I read all of your FAQ's in that time. I have spent probably thirty hours in the last three days reading about A/C units, etc. It's why my head hurts.

In Colorado, we can have hot summers. It's been above 90 for the last week and a half. But the the house I'm buying hasn't gotten above 75 down stairs or 78 upstairs the whole time. Mind you, this is without any A/C or window coverings and the house has been closed up all the time. The builder insulated the heck out of the house. Is your opinion still the same.?

When I look at the savings of higher Seer numbers compared to the payback, you're right, I have trouble seeing how it will pay for the added expense of going to a XR14i. Maybe I'll just stick with what the builder was going to stick in and see how this summer and winter goes. It's not going to cost me anything more to do it later than to do it now. Make sense?

Irascible
07-03-2005, 03:01 AM
If you think the house is built like a Thermos, then yes. Some people will look at these super-duper insulated houses where they literally bought the best windows and insulation that money can buy and shake their heads at the cheap ACs. But that's precisely when a cheap AC makes sense. If you're AC is going to run one hour a day for a few weeks a year then the financial payback on high SEER will never materialize.

When you say "stick with what the builder was going to stick in" I'm not sure what you mean. Do you mean you're going to live without AC? Or are you putting in the 10 SEER units? If you wait too long on the AC then it might very well cost you more. Come January of '06 the new 13 SEER standard kicks in.

beenthere
07-03-2005, 08:04 AM
Instead of going to 14, or 16, stay with 10 or 12, with the conditions you gave for your house.

The 13 seer law next year, isn't to save you money, its to save on global warming by power generation plants.

You might want to get VS 90+ furnaces though.

appreciative
07-03-2005, 10:03 AM
No, i'm talking about just having the builder put in what he had planned on installing, the 10 SEER units and seeing how the first year goes. We close on the house July 15th and plan to move in right afterwards. Yeah, the 13 SEER is kicking in in Jan 'o6, but aren't companies actually going to come out with less expensive versions of 13 SEER units once they have too? I have read that HVAC companies will save the better parts for the higher end models right now, but once the market forces (and DOE and EPA) forces the new 13 SEER, everyone will be competeing at that level for the market share of 13's. So I wonder if prices might come down on the lower end units.

So, I'm thinking that given that I have so many other expenses ahead of me, (window coverings, etc) It might make sense to see how the 10 SEER units work. Everyone I talked to said there is no charge to remove the A/C units. Just a charge to install the new ones.

About the furnaces, the quotes I recieved mean that I would have to recoup 60 dollars a month for 10 years to go from the 2 single stage 80 to the VX 90's. Do you think that will happen?

appreciative
07-03-2005, 10:28 AM
Sorry everyone, I just realized my last posting might have violated the pricing rules. In more generic terms. I have two single stage 80's in. They are brand new. I am wondering if I should pull them out and go with two new XV 90's now, or wait to see how the winter goes and our comfort level. We move into the house in less than two weeks and I was kinda thinking if I were to replace them that I would do it before I moved in.

These horror stories have given me reason to think that maybe I should just leave well enough alone for now. Should I have a second opinion from another company to make sure the furnaces and A/C units were installed correctly? I just had a thorough house inspection and he didn't notice any problems (knock on wood, but the A/C's weren't installed yet). But, I know you pro's know more what to look for than a general house inspector.

beenthere
07-03-2005, 10:44 AM
90% furnaces don't have to be 2 stage.

I would recommend VS blowers for comfort, not money savings.

We don't remove equipment for free, its included in the price, of new equipment, just not always listed.

Its the harshness, of your winter that should determine the eff, of the furnace you put in.

Since the 80's are already in, you might want to keep them.

These are the things normally though of before hand, but in your case not possible to have done.

bigbird
07-03-2005, 10:51 AM
If you ever visit saratoga go look at the firehouse at the gap,They completly remodeled it.I`m doing a custom home off quito rd. now.BIGBIRD,in the concrete jungle of san jose.

docholiday
07-03-2005, 11:15 AM
Heres my thought FWIW. If you plan on being there for quite some time, consider a 13 SEER R-410A system. The reason I suggest this is because next year 13 SEER is the minimum and in 2010 410A will be the only refrigerant. Why? Becuase if you install a 10 SEER R-22 system and someday whish to replace it, you will be looking at a total system replacement. Now I suppose its possible to find a coil that matches a 10 SEER outdoor unit that may even give you 11 or more AND will also match a 13 SEER outdoor unit but the coil will still need changed when you go to R410A.

Also the 13 SEER systems today generally have a few extras. This may include pressure switches not found on builder grade systems. It may also include a crankcase heater and sound blanket. The sound rating among the same brand is generally lower as well but as Iriscable pointed out no so much from brand to brand. You may also see a better warranty.

This is not required but merely a suggestion for you to consider. I too would go with 90+ furnaces but no sense in buying them now, the 80's are already installed. FYI the 80+ furnaces are generally slightly louder than a sealed combustion 90+. Another thing is 2 stage. Make note that 2 stages are for comfort not efficiency. While the operating efficiencies are close the multiple stages alow for more even comfort by forcing longer run times. I suppose in reality you may actually add to the operating costs because of the added run time but the comfort is usually worth it. It takes X btuhs to heat or cool the space over the course of a day, they will burn the same amount of gas but might use a little more power. In cooling, longer run times take you more to EER since there is less cycling.

appreciative
07-03-2005, 12:22 PM
Again, thank you to everyone for all the suggestions. I am a recent widower, raising three small kids and I am a bit overwhelmed and concerned about making the wrong deciscions regarding buying a home. It's been a year of intense looking and three house purchases that fell out because of inspection concerns.

Hey Bigbird, my last name happens to be Bird and I lived right off of Quito Rd growng up. Shopped at Gene's Quito and even worked there during college. Small world.

So, it's sounds like it might make sense to install the Trane XL14i because of the warranties and the compressor sound enclosure versus the XB10 the builder was putting in. Suppossedly the load for each floor of the house was rated at 1.5 tons (the HVAC) companies numbers. The HVAC company is saying that I should go with a 3 ton each (2 A/C 's) because "you don't like being hot". I have read so much about the concerns of overloading, that I am suspiscious (isn't manual J factoring in an percentage of extra load already?).

Also, given that the builder has already installed the two Trane 80's, if I have them pulled out and replaced, how much of a 90% do I need? XV 90's, single stage 90"s, Is the noise substantially reduced? Comfort substantially increased?

Freezeking2000
07-03-2005, 01:05 PM
I would NEVER put a 90+ furnace in un-conditioned space due to potential freezing concerns of the condensation from the unit. Stick with the 80% in the attic, also i find 80% units to be generally more reliable. One service call in 5 years and all your 80-90% savings are gone.

Keep what the builder recommends since that is also whats included for the $$$$.

Irascible
07-03-2005, 01:59 PM
Extended warranties can be had on most any level unit. And sound... that's a benefit. But still the Rheem dealers are just so darned sure that their 10 SEER units are so quiet. :) The 12's are pretty good too.

If you want the better stuff and you do so informed then God bless. I LOVE selling high end stuff. I make more money that way. I just don't like it happening on false premises.