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Discussion Starter #1 (Edited)
Hey guys
I have a Carrier 58SX-100-191JG installed in 1989 and this baby is starting to nickel and dime me. I just patched a repair on the condesation trap drain by glueing it back on to hold on a few more weeks or month? Besides leakes everywhere else from draft motor and seals. Anyways I live in metro Detroit Mi. region so it gets cold here in winter today it is 15 degrees F. The summers hit high 80's-low 90's on average.
My question is is there a brand that any of you recomend as a good unit in the High eff. unit 94.+? One that has a good track record? I will stay away from a goodman unit since I know their history.
The current unit is 110,000 BTU Natural Gas and I have a 2700 sq ft ranch with a walkout approx the same,with half of basement finished. The only complaint I really have with the Carrier is it is all the way on the opposite end of home and the bedrooms/baths are on the other end and the temperture swing is noticeable. Is there a way of zoning in an older home and is it worth it? Oh 1 more thing should I worry about the Carrier AC 38TG Tech 2000 unit or the feed coils on the furnace? I know the AC units last longer then a furnace but should anything be done now because of being the same age? It runs fine as far as I can see. I am just a homeowner trying to get the most knowledge before going out to furnace land.
Thanks for the help Dave
 

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Whether you are comparing the performance of different equipment, or seeking to estimate your potential fuel savings, it is imperative to gain a basic understanding of how manufacturers perform efficiency tests and how test conditions differ from real-world operations. Unfortunately, efficiency ratings will generally not translate directly to fuel savings because similar performance is rarely, if ever, consistently achieved in typical installations.

Manufactures use an ANSI published efficiency test that consists of operating the appliance over a specific period of time, measuring the temperatures of the return and supply air (as well as a few other things), and making a bunch of calculations that result in the published rated efficiency.

Two of the primary test procedures are:
a) allowing the furnace to run at 100% load for 30 min to "soak" the unit with heat.
b) prior to taking their readings, they allow the furnace to run at 100% load for 30 minutes.

As seen from above, the furnace is allowed to run at 100% load for 1 hr where by radiation and cycle losses are minimized. In reality, your furnace may run at 40 min out of every hour on the coldest day of year which results in substantially lower efficiency ratings, than the published ratings due to radiation losses, cycle losses, stack losses, etc....

There are alot of options when purchasing a new furnace; single stage and two stage gas valves, modulating gas valves, condensing furnaces, heat pump/furnace combinations....... the list goes on. The ideal case would be if you can select equipment that matches the load demand in the home on any day of the year. For example, if your home required 20,000 btu of energy to heat the home, then your unit would produce 20,000 btu of energy to satisfy this demand. This example would require the use of a modulating gas valve which are now becomming available on home furnaces.

Education is the key in selecting your unit. You can start by learning about the different efficiencies (AFUE, Steady State, Cycle, Seasonal) and how they relate to the overall yearly savings. Furnace designs have come along way in the last 15 years, ranging from blower improvements to better heat exchanger designs resulting in more efficient units compare to pre-1990 equipment, but don't expect payback periods of less than 10 to 15 years - a new furnace is a long term investment!

Your furnace location ideally would be at the center location of your home, but locating the furnace on one end of the home while supplying warm air to the other side shouldn't be to much of an issue. A properly designed and balanced system would produce sufficient heat to warm each room. Just curious, but where is the thermostat located in the home in relation to the furnace room???

If you are refering to a central, multizone system.......... expensive solution and for that I would definelty hire a professional engineer to design it, but being one of those professional "ding bats" I would look at more cost effective alternatives if you are unable to get enough heat to the otherside of the home.

American Standard is a well designed product, but like others, the controller card has a tendancy of taking a permanent vacation after a few years. I'm sure others in this news group have had good experience wth other products???

Time to sleep......

hope this helps,
A
 

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Discussion Starter #3
Thanks Arthur for your info and education lesson.The thermostat is closer to the furnace end of the home in the dining room next to the kitchen. The furnace is located below the kitchen in the basement. The home is a ranch at 2700 sq.ft on main level and lower basement is roughly the same. I will look more into the ratings like you suggest to understand better. I also know what you mean with stated ratings. I am in the appliance/electronics retail business and companies throw a lot of bs in promoting models.
 

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Discussion Starter #4
Arthur said:
Whether you are comparing the performance of different equipment, or seeking to estimate your potential fuel savings, it is imperative to gain a basic understanding of how manufacturers perform efficiency tests and how test conditions differ from real-world operations. Unfortunately, efficiency ratings will generally not translate directly to fuel savings because similar performance is rarely, if ever, consistently achieved in typical installations.

Manufactures use an ANSI published efficiency test that consists of operating the appliance over a specific period of time, measuring the temperatures of the return and supply air (as well as a few other things), and making a bunch of calculations that result in the published rated efficiency.

Two of the primary test procedures are:
a) allowing the furnace to run at 100% load for 30 min to "soak" the unit with heat.
b) prior to taking their readings, they allow the furnace to run at 100% load for 30 minutes.

As seen from above, the furnace is allowed to run at 100% load for 1 hr where by radiation and cycle losses are minimized. In reality, your furnace may run at 40 min out of every hour on the coldest day of year which results in substantially lower efficiency ratings, than the published ratings due to radiation losses, cycle losses, stack losses, etc....

There are alot of options when purchasing a new furnace; single stage and two stage gas valves, modulating gas valves, condensing furnaces, heat pump/furnace combinations....... the list goes on. The ideal case would be if you can select equipment that matches the load demand in the home on any day of the year. For example, if your home required 20,000 btu of energy to heat the home, then your unit would produce 20,000 btu of energy to satisfy this demand. This example would require the use of a modulating gas valve which are now becomming available on home furnaces.

Education is the key in selecting your unit. You can start by learning about the different efficiencies (AFUE, Steady State, Cycle, Seasonal) and how they relate to the overall yearly savings. Furnace designs have come along way in the last 15 years, ranging from blower improvements to better heat exchanger designs resulting in more efficient units compare to pre-1990 equipment, but don't expect payback periods of less than 10 to 15 years - a new furnace is a long term investment!

Your furnace location ideally would be at the center location of your home, but locating the furnace on one end of the home while supplying warm air to the other side shouldn't be to much of an issue. A properly designed and balanced system would produce sufficient heat to warm each room. Just curious, but where is the thermostat located in the home in relation to the furnace room???

If you are refering to a central, multizone system.......... expensive solution and for that I would definelty hire a professional engineer to design it, but being one of those professional "ding bats" I would look at more cost effective alternatives if you are unable to get enough heat to the otherside of the home.

American Standard is a well designed product, but like others, the controller card has a tendancy of taking a permanent vacation after a few years. I'm sure others in this news group have had good experience wth other products???

Time to sleep......

hope this helps,
A
Thanks Arthur for your info and education lesson.The thermostat is closer to the furnace end of the home in the dining room next to the kitchen. The furnace is located below the kitchen in the basement. The home is a ranch at 2700 sq.ft on main level and lower basement is roughly the same. I will look more into the ratings like you suggest to understand better. I also know what you mean with stated ratings. I am in the appliance/electronics retail business and companies throw a lot of bs in promoting models.
Dave
 
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