Steve Hoch
TVWBB Hall of Fame
Honest question. Can you even get your house down to 70° at night when it's that hot outside?
Feedback and guidance on a replacement 5 ton HVAC, with AC being most important.
- Thread starter DanHoo
- Start date
DanHoo
TVWBB Olympian
Yes. Temp is 83 outside. I've got R30 attic insulation and a quiet cool attic gable fan so it's not really that hot.
On hot nights when I can't open windows I'll set AC to 70 then turn it up to 72 when I go to bed
Steve Hoch
TVWBB Hall of Fame
That's good, those temps work for me too.
TomRc
TVWBB Pro
For a moderate climate such as @DanHoo enjoys, a heat pump is a great solution. In the last quarter of 2023, the industry saw the introduction of units such as the Samsung Hylex and GE Connect series of inverter heat pump outdoor units (ODU’s). These ODU’s offer all of the benefits of a heat pump…high SEER, DC inverter, modulating output, efficient operation, low noise output, etc. The nice part about these units is that they integrate seamlessly with your existing indoor furnace. In Dan’s case, it will require that he change out the R22 indoor evaporator coil at the same time and I would also suggest changing the line set out as well rather than just flushing it. Once installed, this system can provide plenty of cooling a/c and shoulder-season heat very affordably in just about any climate in the lower 48. I wouldn’t be surprised to see it handle most of the year-round load in a temperate climate like Dan’s. As for the furnace itself, I’m a bit of a dinosaur and still like the idea of a traditional gas furnace for reliable heat regardless of the outdoor temperatures. But, this comes from a Northern NY’er whose design day temperature is 1ºF. For simplicity, design temp is a number that the lowest daily temperature exceeds on a 99% basis. For reference, Dan’s design temp is probably somewhere around 40, so we’re talking about a huge difference in climates. Regardless, the furnace can be changed out now or later according to its’ condition and your budget. I’ll go on record any day as saying that the most important day in the life of any piece of equipment is the day it is put in. Brand name isn’t nearly as important as the skill set of the guy / team putting it in. Make sure they are familiar with the brand / product and that they follow all manufacturer’s installation and start-up procedures.
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Jay D in Jersey
Closed Account
Carrier, Bryant, Payne....installed by a competent expert.
LMichaels
TVWBB 2-Star Olympian
My SIL has been looking into heat pump systems. He said the new tech ones can keep (get) home warmed even in our most brutally cold weather here with little to no backup. They're in Elburn IL BTW so really not far from us.
As far as running our AC, I have been using it very sparsely. Thanks to nearly having my breaker panel go up in smoke. The breakers that work the outside unit on ours burned up in back. Had no clue they were what was causing the faults seen on the smart stat. HVAC tech said it was a good thing I hadn't turned it on. He did a temp repair but I have to have my breaker panel replaced. And since one thing I MAY do in maybe near future is get a new Toyota BZ4X I'll want to upgrade.
BTW FWIW, I'm not an electric car evangelist. Actually think they're a bit "dumb". Unless used properly. In our case, I would like a larger vehicle to replace my Highlander. (maybe a pickup i.e. Tacoma or such) or perhaps a mini van.
So I would sell the HL, and trade in our RAV4 Hybrid, (which wife uses for errands and to-from work) with the BZ4X Which would be perfect for her. Same overall size/driving dynamics as the RAV. But, no waiting in long lines at Sam's for gas. She MAYBE drives it 25-30 miles a day. Then it sits.
So, thinking I'll need at least a 150 amp panel
As far as running our AC, I have been using it very sparsely. Thanks to nearly having my breaker panel go up in smoke. The breakers that work the outside unit on ours burned up in back. Had no clue they were what was causing the faults seen on the smart stat. HVAC tech said it was a good thing I hadn't turned it on. He did a temp repair but I have to have my breaker panel replaced. And since one thing I MAY do in maybe near future is get a new Toyota BZ4X I'll want to upgrade.
BTW FWIW, I'm not an electric car evangelist. Actually think they're a bit "dumb". Unless used properly. In our case, I would like a larger vehicle to replace my Highlander. (maybe a pickup i.e. Tacoma or such) or perhaps a mini van.
So I would sell the HL, and trade in our RAV4 Hybrid, (which wife uses for errands and to-from work) with the BZ4X Which would be perfect for her. Same overall size/driving dynamics as the RAV. But, no waiting in long lines at Sam's for gas. She MAYBE drives it 25-30 miles a day. Then it sits.
So, thinking I'll need at least a 150 amp panel
Bob Bailey
TVWBB Guru
I'm with @Brett-EDH on only replacing the AC unit. Unless you're having problems with the furnace, leaving it alone will save you a chunk of change. Just had our AC system replaced and saved about 2.5K by leaving the furnace alone. Even if it needs to be replaced later, there isn't much redundant labor involved, since it sits on top of the evaporator unit.
As @LMichaels says, there aren't that many actual manufacturers of central AC systems. Kind of like household appliances, many times the only difference from one brand to another is the badge.
Just stick with a major brand and you should be fine. Carrier, Trane and Lennox come to mind. Our new system is Lennox and very quiet. The contractor is what you need to be careful about selecting.
As @LMichaels says, there aren't that many actual manufacturers of central AC systems. Kind of like household appliances, many times the only difference from one brand to another is the badge.
Just stick with a major brand and you should be fine. Carrier, Trane and Lennox come to mind. Our new system is Lennox and very quiet. The contractor is what you need to be careful about selecting.
DanHoo
TVWBB Olympian
I have an 8KW PV solar system, 24 panels. Solar is a must-have in my situation. My elec costs without Solar would be insane.
It was a 9 year break even at 2018 elec costs and with elec rates of PGE going up so high, I estimate break even was last year. My net annual electricity costs are about $100 a year.
Brett-EDH
TVWBB Olympian
Solar. Owned. 12 panels 4.08kW system. My sell price of excess power is $0.074 kWh and my buy price varies per our summer time of day rates. I’m estimating that I’ll build up credit outside of AC season to substantially reduce my annual electricity costs.
My previous home ran around $1600-1700 a year on electricity costs. New home I’m projecting around $300 annual costs.
All appliances except my tankless water heater and a 36” range cooktop are now electric.
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DanHoo
TVWBB Olympian
Brett has SMUD and I have PG&E. I'm guessing a $1600 annual electric costx from SMUD would be over $ 5K for a PGE customer with the same usage.
SMUDs most expensive peak rate is lower than the PGEs least expensive off-peak rate. PGE customers are adopting solar with battery backup to survive the insanely high rates and frequent power outages.
PGE
Brett-EDH
TVWBB Olympian
And PGE no longer buys excess power from solar generators, correct? So you have to have a battery system to even make it all worthwhile. PGE has gone insane.
DanHoo
TVWBB Olympian
I have Net Energy Metering aka NEM 2.0 ( NEM 2018 edition). My surplus power is credited to my account and I have an annual true up.
If at the end of the year I generate more power than I use It is credited at a very low wholesale rate. My true up has been less than $100 each year except for last year when it was $350 because the inverter failed I had four weeks without power generation.
NEM 3.0 is the current plan in place and it is more favorable to utility companies and battery storage is needed ( also a high initial cost ) to manage the rates, but I haven't researched this. my NEM 2.0 plan remains until 2038 as long as I don't increase the generation by more than 1KW or 10%
Adding batteries is not cost effective for me. It would add convenience for a power outage but I would need a very large battery array to run my A/C and for me it isn't worth it.
Oooffffff.
Had the local HVAC shop out (his Dad originally installed this system in '93 when the house was built.) At a minimum, 3 lbs. of R22. No, that ain't happenin'. The furnace is an ~80% efficient, and it'd probably be a good idea to just replace the whole shootin' match at this point, 97% efficient natural gas furnace with a new 2.5 ton AC (think he said 16 seer.)
I asked about heat pumps. According to him, with our electric and gas suppliers here in town, the payoff is a lot longer due to no off hours rate reductions and a few other things. In town, he sets the switchover point to 30 F, outside of town, it's about 5 F. The additional rebates from the energy suppliers and income taxes would offset about half of the heat pump (air to air) premium. The remaining premium would take a long time to pay back from decreased energy usage.
Brands..... He's suggesting either American Standard (which is what we have) or Armstrong for furnace & A/C. Heat pump, he will only sell American Standard.
Oh..... southeastern MN. I expect to see a couple of weeks annually at -10 to -20 F. According to https://energystar.gov, 99% heat design temp is -8 F and the 1% cooling temp is 88 F. A backup heat source is absolutely mandatory here. The house is fairly well insulated, and does have nearly new windows. Photovoltaic panels on the roof and batteries in the basement are just not in the cards right now.
What else do I need to be looking at, what other questions do I need to ask? The heat pump option is attractive from a purely energy efficient standpoint, but the payback looks to be rather long. I can't see just dumping $500 of refrigerant into the system without any idea of where or why it's gone (okay, besides time.)
Slight side note.... I've apparently surprised him by NOT demanding that it be fixed or repaired tomorrow.
Had the local HVAC shop out (his Dad originally installed this system in '93 when the house was built.) At a minimum, 3 lbs. of R22. No, that ain't happenin'. The furnace is an ~80% efficient, and it'd probably be a good idea to just replace the whole shootin' match at this point, 97% efficient natural gas furnace with a new 2.5 ton AC (think he said 16 seer.)
I asked about heat pumps. According to him, with our electric and gas suppliers here in town, the payoff is a lot longer due to no off hours rate reductions and a few other things. In town, he sets the switchover point to 30 F, outside of town, it's about 5 F. The additional rebates from the energy suppliers and income taxes would offset about half of the heat pump (air to air) premium. The remaining premium would take a long time to pay back from decreased energy usage.
Brands..... He's suggesting either American Standard (which is what we have) or Armstrong for furnace & A/C. Heat pump, he will only sell American Standard.
Oh..... southeastern MN. I expect to see a couple of weeks annually at -10 to -20 F. According to https://energystar.gov, 99% heat design temp is -8 F and the 1% cooling temp is 88 F. A backup heat source is absolutely mandatory here. The house is fairly well insulated, and does have nearly new windows. Photovoltaic panels on the roof and batteries in the basement are just not in the cards right now.
What else do I need to be looking at, what other questions do I need to ask? The heat pump option is attractive from a purely energy efficient standpoint, but the payback looks to be rather long. I can't see just dumping $500 of refrigerant into the system without any idea of where or why it's gone (okay, besides time.)
Slight side note.... I've apparently surprised him by NOT demanding that it be fixed or repaired tomorrow.
Brett-EDH
TVWBB Olympian
Really depends on the actual dollars cost difference.
$7k difference would be a lot. But it really comes down to the numbers. Heat pumps are better technology and maintain a more consistent temperature so long as the fan is infinite variable speed.
For $3k more I’d buy the heat pump system. But it depends on your actual numbers.
The installation premium for the heat pump is on the order of $5k, rebates would bring that down to $2.5-3k.
There are some other useful features with the heat pump, like a whole house dehumidifier, and running the compressor at load requirements as opposed to all out.
The mistress of finance & I will have to have a long talk once I get the quote. I'm certainly not opposed to the idea of a heat pump here, but it cannot be the sole heat source.
LMichaels
TVWBB 2-Star Olympian
My system (I don't recall the SEER rating on the AC but it was the highest one they could install for it's size) and the furnace they installed a 98.5% unit and the whole thing requires a special t/stat to work at max efficiency as it monitors current and predicted weather, and adjusts itself accordingly. Total installed cost was right about $10K
Brett-EDH
TVWBB Olympian
around 2200 sq ft home?