replacement system for a small house

mewsicianFebruary 17, 2013

I've been reading this forum for a couple of hours, looking for information to help me decide on a replacement system for a 10 yr old American Standard. I've liked it, except for the draftiness of the heat pump in the winter. AC is required here for about nine months of the year, and heat or nothing the other three. The AC works great. My summer and winter indoor temps. are set at 76 and 68 (occasionally 66).

Here are the numbers (model or serial) taken from my written estimate 10 yrs ago, for my all electric system. It's a 10 SEER, with an F200 Honeywell whole house filter, 2 ton. I would consider replacing it with the same or similar system if the heat pump is as far gone as I think it is, but I haven't had it looked at yet

Air handler TWE024C140A
Cond. Unit 6H0024A100A
Heat Strips BAYHTR1410
Thermostat T8411R1028

If it is a good idea to replace my current system with the same or similar system, I'll do that if a first or second repairman suggests it (with a 13 SEER or maybe 14 SEER), and just add a second sweater and blanket in the winter. If it's not a good idea to replace this model with a current version of it, I have a couple of questions.

1. Are two-stage compressors and high efficiency single stage furnaces (non heat pump) only used in systems larger than mine?

2. Would these two items help lower my utility bills?.

My objective is to lower my utility bill. Here in north Florida we have the highest utility rates in the state (and recently had a rate increase). A $137 electric bill for 1200 kw last month is pret-ty high, considering that the fees, service charges, fuel adjustment costs, etc. brought the total bill to $186 (my average total bill is $140 to 160, with the occasional $110). Before the rates went up, half of my bills in any given year were under $100.

We have one large company that installs American Standards here, a company which until recently has had a good reputation, and two other, independent people who could install a new system for me. Reliability of HVAC people in this city is only fair, unfortunately. They don't even blink when they say: we don't give written estimates. The company that installed my current system is out of business.

I have a 32 yr old well insulated, almost 1,100 sq. ft brick house, with a new roof, R-38 in the attic and R-11 in the outside walls.

I would soooo appreciate some advice.

This post was edited by mewsician on Mon, Feb 18, 13 at 13:20

Thank you for reporting this comment. Undo

Just to be clear, you have a HP condenser or straight AC condenser and heat with heat strip?

Why are you considering replacing your existing system?

Just so you know, Trane and American Standard are sister companies.

I would look at 2 ton AS Heritage 13 with GAM5030 air handler or TAM7030
var speed air handler. Add a 7 KW heat strip. Ask for HW mdl 8321 for best dehumidification in cooling.

I see no reason for a two stage condenser. A waste of money. Since cooling is more important to your location, you want the higher SEER. The TAM7-030 air handler paired with the Heritage 13 condenser gets you to 15 SEER. I would expect your cooling costs to be reduced apprx 20%.

American Standard is quality HVAC. I would recommend only using an AS authorized dealer.


    Bookmark   February 18, 2013 at 5:56AM
Thank you for reporting this comment. Undo

Thank you very much for your answer. I'll answer your questions as best I can, but I'm not an expert.

1. It's my understanding that I have a straight AC condenser and heat with heat strip.

2. I'm not considering a new system until I speak to a repair person. I just want to be prepared because of the quality of the local HVAC people. We are at the mercy of repair people, you know. We don't know this from that where HVAC is concerned. If a new system is recommended for me, I can get a second opinion, of course, but I wanted some information first, and this forum has real experts on it.

There's another reason I asked my questions about a new system. With R-22 being phased out and the new minimum 13 SEER requirement, I could get into trouble if my heat pump needs replacing. I've read about matching the SEER of your AC and heating, and if they can't matched, it sounds to me like I'd need a whole new system. At the moment my heat is running about 50 min an hour (at intervals) and not heating well. I may need new heat strips.

It turns out that I was lied to about a heat pump being required in this county. It's not. I would not have gotten one for this size house and find it much too drafty, hence my questions about a new system. I'd really prefer a non-heat pump system.

    Bookmark   February 18, 2013 at 10:32AM
Thank you for reporting this comment. Undo

The 6H0024 would be a heat pump (2T), and you have an indoor air handler with electric back-up heat (10 kW).

How would you plan to heat your home without a heat pump? Just electric strips in the furnace would be very costly to operate. Any nat. gas service available? Newer heat pumps have come a long way in comfort and performance -- you'd be sure to notice a difference in comfort if you invested in a new 2-stage heat pump system, or even a single stage heat pump with a variable speed air handler. I have a 2-stage heat pump, and can tell you there is a large difference in comfort and even temperatures over the previous single stage 10 SEER unit (similar to what you have now).

With that said, a 10 year old heat pump isn't that old, but no one can say how much longer it's going to last. Repairs will tend to be costly with R22 costs rising, demand increasing, and availability decreasing. Let us know what the technician finds. When was the last time you had maintenance done on your system (i.e., has the refrigerant charge ever been checked)?

A properly maintained 10 year old system, properly installed, should not have any problems keeping you comfortable. I see no reason to replace your system unless there is a major issue.

This post was edited by ryanhughes on Mon, Feb 18, 13 at 12:06

    Bookmark   February 18, 2013 at 11:56AM
Thank you for reporting this comment. Undo

"My objective is to lower my utility bill."

It would be more efficient to heat your house with a heat pump than electric heat strips even though the heat strips can provide enough heat for your location in Florida.

Your AC still has a lot of life left. But if you do want to replace it I suggest looking at a heat pump with a SEER rating with a minimum of 15-16.

    Bookmark   February 18, 2013 at 12:00PM
Thank you for reporting this comment. Undo

"Electric back-up heat". . . hmmmmm. That sounds like it might not be connected to the heat pump. Is that correct?

    Bookmark   February 18, 2013 at 12:05PM
Thank you for reporting this comment. Undo

Sorry, Ryan, your whole message did not show up before my hmmmm answer. Thanks for your answer and the info about newer heat pumps.

I have had two maintenance checks per year for the whole life of my system, which will be 10 years in May.

I'm waiting for a call right now to see if I can get a repair person here tomorrow. It was 26 here last night (a hard freeze) and, per usual for this area the temp has risen to 55 right now, hard on HVAC. At least I won't need the AC today, but later this week it will get up to the mid 70s. The in between weather here is brutal, often 30-40 deg. changes from morning to night.

    Bookmark   February 18, 2013 at 12:15PM
Thank you for reporting this comment. Undo

You may not want to hear this but the draftiness you make mention of has nothing to do with whether your system is straight AC or HP .

I believe it would be a mistake not getting a HP system when or if you replace. It would be helpful to know if you have a HP system or straight AC and the size if you have a heat strip. It crosses my mind about a bait and switch from the dealer of the equipment installed. Both the outside and condenser should have ID plates with complete model numbers. Suggest you check on this information rather than relying on old quote.

Electric heat strip heat is expensive. While not uncommon, it is rare that heat strips go bad.


    Bookmark   February 18, 2013 at 2:20PM
Thank you for reporting this comment. Undo

The HVAC guy arrived yesterday afternoon late, checked my entire system, determined that the heat strips are working, defrost cycle is working, etc. Everything was working correctly until he got to checking the thermostat. He determined that the thermostat (a Honeywell), was making the heat strips turn off early unless there is a six degree temperature difference between the room temperature and the temperature I set. The blower was continuing to blow cold air instead of heat, cycling on and off, over and over. Odd. . . don't know how long it's been like that, but I'm guessing a few months and the effect was magnified by two nights of 26 deg. temperatures.

So he recommended a new thermostat, and I let him put one in. After a slow start last night, the heat did come on and had a heating effect like it was supposed to rather than the air conditioning effect it has had for the last few nights. It still seems a little too cold and blowy to me, but I'll have to wait until my nose bleeds stop (from the dryness with all that blowing) to give it a good assessment. Even with a vaporizer running, the humidity is down from 55% to 38%, but I expect that will slowly change.

Tiger: This repairman determined I do have the system that was proposed for me. Thank you for mentioning that. I do have a HP system, and the heat strips are working at full capacity. Given the excellent service my AC gives, I'm sure you're right about keeping a heat pump system.

I can't tell you all how much I appreciate your advice. Thank you!! This is SUCH an invaluable forum. I'll keep the information on a new system for a few months, of course, just in case!

    Bookmark   February 19, 2013 at 10:04AM
Thank you for reporting this comment. Undo

UPDATE: My system is working much better now. After using my heating with the heat pump a couple of nights when it was very cold at night (20s and 30s), I switched to using emergency heat. Using that set at 68 or 69 deg. makes it very toasty inside and not drafty or blowy at all. Is this a bad idea, using emergency heat for very cold nights? We have about 12 nights a year when I would need to do this. I have very dry eyes and really need to run a vaporizer when the humidity goes below about 40% inside. Even though using emergency heat may be more expensive, I think it will be better than having continual eye and throat infections from the air blowing so much. With a vaporizer running using emergency heat, I can keep the humidity at 45%. Any opinions on using emergency heat for cold nights for our in between weather?

    Bookmark   March 4, 2013 at 9:23AM
Thank you for reporting this comment. Undo

using heat pump vs electric strip doesn't
change humidity in the air inside your house.

it doesn't matter how you warm the air
it will still have the same % of RH at a given temp.

adding vaporizer in winter may be you need
for your condition.

summer time RH, both indoor and outdoor
will be much higher.
same allergins in winter & summer how does it
effect you in summertime?

best of luck.

    Bookmark   March 4, 2013 at 12:49PM
Thank you for reporting this comment. Undo

If you want to lower your bills, don't use Emergency Heat. If you want to raise your bills substantially, then use Emergency Heat.

    Bookmark   March 4, 2013 at 8:07PM
Thank you for reporting this comment. Undo

Thanks for both of your replies.

energy rater: It's because the RH goes so low using the heat pump for heat that I asked my question. I have determined by staying up for two nights and timing my heat pump blowing so much one night versus using just emergency heat the next night that the RH is substantially lower using the heat pump. The heat pump blows for 45 to 50 minutes an hour. The emergency heat goes on for about 10 minutes and then turns off. The RH using the heat pump is more than 15% lower than it is using emergency heat. In the summer time, all I need to do to equalize the humidity is open a door a couple of inches. I don't have allergies.

Perhaps I was not clear with my question. What I want to know is: will using emergency heat for about 12 nights a year damage my system?

I appreciate your help.

    Bookmark   March 5, 2013 at 8:57AM
Thank you for reporting this comment. Undo


with electric strips on the blower still blows. the air handler still moves the same amount of air as when in heat pump heating mode.

you have convinced yourself that the HP heat is contributing to your eye & throat issues.
so that is where you are.

in the summer...your RH is too LOW inside so that you have to open a door to let more humidity inside?
hard to believe.

best of luck.

    Bookmark   March 5, 2013 at 11:20AM
Thank you for reporting this comment. Undo

In emergency heat mode, electric strips on, the blower does indeed blow air, warm air, for 10 minutes an hour. Then the unit stops and does not come on again for another hour.

In heat pump heating mode, the air handler IN THIS HOUSE blows warm air for about 7 minutes and then cold air for 45-50 minutes. I have not convinced myself of anything. I stayed up for two nights timing the cycles, one night in heat pump mode, the other night in emergency heat mode.

Ten minutes in one mode does not equal 45-50 minutes in the other mode.

Is this pattern the way these two modes should be working?

    Bookmark   March 5, 2013 at 2:19PM
Thank you for reporting this comment. Undo

No. It should blow warm air in HP mode all the time. 'Warm' is a relative term here. Depending on its efficiency, if it is say 40f outside, the HP should blow 85F air. Emergency heat would probably blow +100f air.

Neither should blow cold (below 70F) air.

    Bookmark   March 5, 2013 at 4:41PM
Thank you for reporting this comment. Undo

weedmeister: Thank you very much for your answer. I can use that information when talking to my repair man. I appreciate your help.

    Bookmark   March 5, 2013 at 7:56PM
Sign Up to comment
More Discussions
How to heat this room?
Hi folks! First post in this forum. I live in ec Iowa....
What's your average gas heating bill in Winter?
I just bought a house in Richmond, VA. Just called...
Honeywell th6320R Thermostat
My Honeywell TH6320R thermostat (communicating with...
HVAC design
In determining the HVAC system to use in our new construction,...
No Fully Trained Mini Split Installers
Reading threads about mini split heat pumps I got curious...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™