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Paul.Raulerson

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We have always had heat pumps, and in general, they have always been pretty reliable for us. However, we now are at the point where we need to replace two heat pumps (again!) and are considering using an electric furnace instead.

The two systems are a 1.5t and 3.0t Ruud/Rheem system, installed in 2005. They have been cranky and not doing a good job almost since they were installed. A current list of the repair costs on them (including service trip charges and such) have added up to a bit over $- $ of which in the last four months.

Since we live in the Austin area, we heat less than 30 days per year on average, and when heating, I am relatively sure the aux heat strips are on a lot during that time as well. During the brief heating season, our electric bill rarely reaches $180/month. During the peak of the cooling season, we often see $400/month electric bills. Often four of five of them, and they ar braced by bills ranging from $240-$280.

This leads me to believe that buying an A/C system with an electric furnace, rather than a heat pump, might allow me to push more money into a higher end A/C system, even at the risk of getting a $300/$400/month bill once or twice a year. Seriously, we rarely turn on the heating, even when the outside temperature dips into the low 40's. The house retains a lot of warmth, as it is fairly well insulated and constructed with a very thick layer of stucco.

Another reason for this is the two Ruud units outside, after being repaired with new fan motors and caps, sound incredibly loud. Being right outside our living room and kitchen, I can assure you they are terrifically noisy and irritating.

The contractors we are talking to to obtain bids are all recommending either Lennox, Trane, Carrier, American Standard, or Daiken. We are tending towards the brands we see more of, like Lennox and Trane, but have not made up our minds about it yet, but all those brands carry both normal A/C units and Electric Furnances, as well as heat pump units.

Having read many many posting here, it seems that HP's are almost *always* recommended over this configuration though. So- I am asking for your opinion, and hope I gave enough specifics to allow you guys to offer those opinions. Thanks! I see we are not supposed to discuss budget, but we are able to replace both units financially now, and that is probably one of the better drivers. I would rather spend a good amount one time than $ here and $ there and so forth.


Thanks!
-Paul
 
Hello Paul,
Step one is to have your house measured by a contractor who will perform a Manual J load calculation. This will determine the correct size heat pump or AC for your house. A system which is oversized will not perform properly and can break prematurely. It will also be noisy. You'd be surprised at how common it is for a lazy contractor to skip the load calculation and use "rule of thumb" to select equipment. You may find that your current equipment is too big which has led to breakdowns.
Second, have the duct system inspected and ideally have it tested for leaks. If the ducts are entirely inside the conditioned space, leaks won't be critical. The ducts must be big enough to accommodate all the air flow needed by the equipment or that will cause noise and poor performance.
Third, have a home rater check your house by performing a blower door test to determine how leaky the house is. He (or she) can recommend repairs or upgrades to minimize the size equipment which is needed.
Fourth, find a contractor who is conscientious in their work. This is not necessarily a big-name company or a "factory authorized" dealer. It will be one who takes pride in their work and performs a full set-up test after installation. This will include measuring pressures, temperatures, and air flow volume and pressures.
Austin is quite different from southern Ohio, so my advice to get a heat pump instead of an AC with an electric furnace may not be applicable to your area. I would also recommend that your fan/coil unit have a variable speed blower for improved de-humidification and comfort.
 
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Discussion starter · #3 ·
Hello Paul,
Step one is to have your house measured by a contractor who will perform a Manual J load calculation. This will determine the correct size heat pump or AC for your house. A system which is oversized will not perform properly and can break prematurely. It will also be noisy. You'd be surprised at how common it is for a lazy contractor to skip the load calculation and use "rule of thumb" to select equipment. You may find that your current equipment is too big which has led to breakdowns.
Second, have the duct system inspected and ideally have it tested for leaks. If the ducts are entirely inside the conditioned space, leaks won't be critical. The ducts must be big enough to accommodate all the air flow needed by the equipment or that will cause noise and poor performance.
Third, have a home rater check your house by performing a blower door test to determine how leaky the house is. He (or she) can recommend repairs or upgrades to minimize the size equipment which is needed.
Fourth, find a contractor who is conscientious in their work. This is not necessarily a big-name company or a "factory authorized" dealer. It will be one who takes pride in their work and performs a full set-up test after installation. This will include measuring pressures, temperatures, and air flow volume and pressures.
Austin is quite different from southern Ohio, so my advice to get a heat pump instead of an AC with an electric furnace may not be applicable to your area. I would also recommend that your fan/coil unit have a variable speed blower for improved de-humidification and comfort.
Thanks for the tips, I did not realize that a unit that is too large can cause problems. The noise is with the outside units mostly, the inside isn't bad though you can hear a roaring with the blower on. The house is not very leaky, just around one door I need to weatherstrip. Opening a door always results in a strong outflow current from the house, so I am wondering maybe the units are too large and is it possible they over-pressurize the house? I will ask for the "Manual J load" calculation and also require the duct system be inspected and tested as you recommended.

Finding contractors is not always as easy as it sounds. A lot of times, the contractors just want to come in and do their thing, and not listen to us home owners - and vice versa. I like a lot of the contractors, but trying to evaluate the differences between then is much more difficult than it seems. Everything seems to be variable, from equipment to opinions to warranty to pricing to the time in business. How can the cost for an install with the same equipment vary thousands of dollars? It is quite a chore to dig out what am missing so I can make a good choice.

Is it relatively safe to assume that if I stay with "name brand" equipment, like Lennox or Trane (American Standard), etc., the quality of the equipment will be comparable? Then I can choose on features?

For example, I like the Lennox Signature line, because by specification they are quiet and can support a solar power installation. (Who would have thought that? Cool...)
But the comparably priced Trane unit has a variable speed compressor, to get the same feature with Lennox means jumping up a level, I think.

Also, from a consumer viewpoint, not having the list pricing on units available for comparison is a real pain. In the example above, if I knew the jump from the XP21 to the XP25 was X number of $, it would make deciding things a lot easier. It seems to frustrate some contractors to be asked for a range of options to choose from though.

Not really complaining, though perhaps venting a little frustration at how difficult this decision is. So many factors and not enough knowledge to make a good decision. Appreciate you sharing some of your expertise with us. At least we know now three things we need to get. (Manual J, duct test, and a "blower door test." ) Appreciate it. :)

-Paul
 
I would bet there are many in your area with electric heat only, and the heat cost is negligible, if well insulated.
But I'm up north, and it would be insane up here.
 
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Discussion starter · #6 ·
If you are located in Austin, a straight electric furnace without a heat pump will not pass the city inspection.
I am in Georgetown actually, but I gotta ask- why in heaven's name would it not pass inspection? Gas furnaces surely do. We actually would use gas, but there isn't any gas service in our area.

-Paul
 
Back to original question, would definitely recommend getting a heat pump over strip heat. If your current heat pump is using strip heat most of the time then the heat pump is probably not functioning properly. Your winters should seldom need backup heat to supplement the heat pump.
 
Discussion starter · #9 ·
Back to original question, would definitely recommend getting a heat pump over strip heat. If your current heat pump is using strip heat most of the time then the heat pump is probably not functioning properly. Your winters should seldom need backup heat to supplement the heat pump.
What advantage does a heat pump really have in this climate? I must admit, we have been here for 15 years now, and I don't even own a heavy jacket. We moved down from PA where we had heat pumps with a second source that was gas.

I really always thought heat pumps only provided savings in the winter with heating. They are usually not as efficient as straight A/C units are they?

Guess I need to add finding out what the code is here in Georgetown. That could obviously make a bit of difference. House is 2250sq ft, with 1400 of that on the first floor.

Paul
 
an electric furnace is 100% efficient. meaning that 100% of the electricity put in, produces heat.

a heatpump is over 300% efficient. ESPECIALLY at warmer temps. in austin, where the temps rarely get below 40, the heat pump would produce wonderful heat, with very low power bills, during the short window the house needs heat.

read my tag line... NOTHING is more important than the installation of the system... I'd take a well installed ultra cheap brand over a poorly installed top of the line system.

yes. if the system is oversized, the home will not be conditioned properly, and if the ductwork is undersized, the equipment will suffer rapid degradation... if the ductwork is also poorly made, and installed, MASSIVE energy will be wasted and the home and your comfort will suffer.
 
The advantage of heat pump is energy savings. Does not effect cooling cost. Your contractors would have told you if heat pumps are required. Have them quote job both ways and you will make the decision.
 
Discussion starter · #12 ·
The advantage of heat pump is energy savings. Does not effect cooling cost. Your contractors would have told you if heat pumps are required. Have them quote job both ways and you will make the decision.
That sounds like wise advice. When I checked the same model A/C vs Heat pumps, the SEER ratings were a little higher on the AC Only units. For example, 21.5 vs 23.5. Will two points make that much difference? How about if it is between 16.5 and 19?

I guess I am hoping to put the money towards where it will continually save us the most recurring expense, and also have the best chance to avoid a lot of expensive fixes. I am learning from you guys that the ducts had better be the right size for the unit installed, as well as clean and not leaking.

Assuming that I understand what you guys are saying then, if there is a problem with the ducts, fix that first even if it means going with a slightly lower performance unit because of the repair cost. Make very sure the contractor does a "Manual J" sizing (and assuming I get a copy of it) review that to understand why they are recommending what size unit. Also get a door blower test.

Assuming the ducts are okay and pass the inspection, buy the best units I can afford with the features I like best. To me that means variable compressors and airflow rates. At that point, decide between HP or AC + Electric furnace for both units, and tell the contractor "go!"

Sound like a good plan?

-Paul
 
Assuming the ducts are okay and pass the inspection, buy the best units I can afford with the features I like best. To me that means variable compressors and airflow rates. At that point, decide between HP or AC + Electric furnace for both units, and tell the contractor "go!"

Sound like a good plan?

-Paul
With the exception of Nordyne. No one has had their variable speed compressor system(conventional, not ductless) out for any good length of time. So thinking of them as low cost to maintain is not practical. 2 stage with VS blower is a better option.
 
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Would it be urbane to just pick one contractor and have them do the manual J and "blower door" test? Pay one contractor to do it, I mean?

I think we really need to know the condition of the ducts and the right size we need to cool the house before deciding on any one contractor. Two contractors have offered to do this for free, and one wants about $ to do the tests. (Though that contractor was testing me by throwing out that price, I am sure. :))

Each contractor is all over the board on their recommendations, and I am having trouble convincing them to come up with a solution that solves the problems first, before they start worrying about price. I have the strong feeling that HVAC contractors must get ambushed by tricky consumers all the time, they are as wary as mice in an elephant pen...

We are being upfront in asking them their opinions, and giving them each the exact same information and what our ideas are. We also are clear and upfront that we are talking to multiple vendors, and we want to make a choice by the end of next week.

We also make clear that the cost of any needed duct repairs may affect the final choices of equipment, depending upon what we find in the testing.

I honestly would like them to think a bit outside the box.

If they are unwilling to, for example, tear down ceiling or floor to get to a badly damaged duct, I think it only fair that they then propose some other system that meets the needs. After all - why would I spend 70% or more of the budget on a solution that does not solve our concerns?

(grin) Is there like some secret code I can use so they know I am serious and not trying to put them on the hook? I gently deflect their questions about budget, which really puts some of them on edge. Do you guys think it woukd help if I just told them we funded the project already to 130% of what we believe the real cost will be? I do not want to really tell them the budget, because that seems to lock their thinking into solutions that only fit what $$ I tell them. I really want them to feel free to tell me, ballpark pricing, what their best solutions are. We might choose to go with a Chevvy vice a Mercedes, but I do want that to be our choice.

Anyway- we are narrowing in on the possible system designs, none of which appear to be that unusual. At least one of my friends has a system like one of the ones below, which is of course, where we got the ideas from.

(1) Replace the existing units with two high end heat pumps or some variant along those lines.

(2) Replace with two high end A/C units and two electric furnaces.(Elec. cost here is $0.028 kw/hour. Pretty cheap. About a penny more over some number of kw/hours each month. )

(3) Move the upstairs air handler downstairs, to avoid another catastrophic water leak in the future. Really want to put it in garage. Requires some duct work.

(4) Put in a single high end HP or A/C w/electric furnace, and run new ducting to zone the upstairs. Obviously requires some ductwork.

Thanks again for sharing your thinking and opinions. Please feel free to tell me I am being a bit of an ass if something in this approach is making the contractors uncomfortable. I assure you it is ignorance on my part, and not malice! We want these guys to come up with great solutions, and we will work out a contract and pricing that if both fair and acceptable to both parties to implement the one we choose.

Do you guys really get so few customers who work that way? I can't really imagine any major undertaking done any other way!
 
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(2) Replace with two high end A/C units and two electric furnaces.(Elec. cost here is $0.028 kw/hour.
Pretty cheap. About a penny more over some number of kw/hours each month. )

I assure you it is ignorance on my part, and not malice!
........................
 
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Discussion starter · #18 ·
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