JimRB
Veteran Member
I would suspect most power companies will do an energy audit for free. This site suggests about 3 times more insulation than you have. Insulation Fact Sheet
Heat pumps
- Thread starter joemd11
- Start date
- Views: 9925
OP
joemd11
Platinum Member
- Joined
- Jan 1, 2010
- Messages
- 991
- Location
- Western Pa
- Tractor
- LS R3039, Power King 1614, Simplicity Soveriegn 75th Aniv model.
buckeyefarmer
Epic Contributor
My power company does the same thing, wish they would stop wasting my money doing it. Course they don't list the sf of the comparison houses, or if they are all electric, etc.... They are trying to sell you new energy efficient items.
My highest month was 3740, however they estimate every other month, and the month before was estimated low. I've averaged 1233kwh/month since I built the house in 1997, and 1577 kwh/month over the last year. I use more electric now with all geothermal, but I lost that huge oil bill I used to have.
$/month numbers are meaningless without more info. I've averaged anywhere from $58 to $198 per month, a lot depends on the weather.
Last edited:
buckeyefarmer
Epic Contributor
It's not Free, I suspect the OP has the same power company I have. We pay for this "free service" every month in our bill, as an energy program. This is the program that gives us the "free" cfl bulbs (mine came broken). I think last year it cost me over $100 for this "free stuff" that I don't want.
crackerjack222
Silver Member
- Joined
- Sep 12, 2011
- Messages
- 243
- Tractor
- 4430, Ford 7000, MF235
Prior to last April I had an open loop geothermal, installed in 1994. It claimed an SEER of 15. Last April I had a Trane variable 19 SEER 5 ton conventional heat pump unit installed in my all electric home in south central Tex. My electric usage dropped significantly with the Trane unit. The avg KWH for June, July Aug and Sept of last year was 1699 per month. The highest monthly usage since then was 1514 kwh in December.
Disclosure: our house is two story and 4000 sq ft with only two of us living here. I have a six zone system using motorized ducts. The house is reasonable tight with good insulation and has ridge vents.
The Trane system has kept a much more even temp throughout the house, both in summer and winter. I was concerned at first since I noticed the compressor running a lot. The thermostat shows at what % speed it is running (it is variable from about 30% to 100%) and I see it much of the time at 31%. The electric backup strips have kicked on from time to time, usually when I adjust a thermostat to warm up a zone.
I am very happy with the system.
Disclosure: our house is two story and 4000 sq ft with only two of us living here. I have a six zone system using motorized ducts. The house is reasonable tight with good insulation and has ridge vents.
The Trane system has kept a much more even temp throughout the house, both in summer and winter. I was concerned at first since I noticed the compressor running a lot. The thermostat shows at what % speed it is running (it is variable from about 30% to 100%) and I see it much of the time at 31%. The electric backup strips have kicked on from time to time, usually when I adjust a thermostat to warm up a zone.
I am very happy with the system.
LD1
Epic Contributor
I am surprised they do that. My elec company has phased in over the last two years their smart meters. Where they dot even need a meter reader anymore. They can access usage from the office. And can also look at a glance if you are out of power.
Then all of this info I can access online and look at a nice chart showing daily, monthly, yearly, or whatever usage. And make yearly or monthly comparisons.
What is the winters like there in central TX?
In milder climates where winter temps never get really cold, Geothermal isnt worth the money IMO. Geothermals are really beneficial though in colder climates (like mine) where there is little to no heat to extract from the air. But there is plenty to be had from 40 degree earth.
Both systems operate on the same principal of heat exchange. Geo exchanges with earth (usually constant 40 degree in my area). Air units exchange with air. If you have mild winters with mostly 40 degree + days, you dont gain much with geo. And actually with a 50-60 degree day where you just need a little bit of heat, a air HP can be even more efficient than a GEO system making an exchange with 40* water.
That in combination with your new Variable speed unit, is most likely why your bills are less. I would venture a guess that if your climate is milder like I suspect, A new high end Air unit vs a new Geo there would be no appreciable difference. In which you made the right call going with a less expensive air unit.
crackerjack222
Silver Member
- Joined
- Sep 12, 2011
- Messages
- 243
- Tractor
- 4430, Ford 7000, MF235
[
What is the winters like there in central TX?
That in combination with your new Variable speed unit, is most likely why your bills are less. I would venture a guess that if your climate is milder like I suspect, A new high end Air unit vs a new Geo there would be no appreciable difference. In which you made the right call going with a less expensive air unit.[/QUOTE]
Our winters are very mild in cen-TX. This winter we have only seen a few nights less than freezing and no days where the temp did not get above freezing. As I write this our temp is 41* and overcast. Forecast is for 35-36 tonight and them warming up into the 60s-70s later in the week. It will be spring here in a week or two.
Our challenge is ac in the summer. Our summer can last six months and for two-three months we can see temps in the high 90's to about 105.
The geo system I had, pumped water from the 400 acre lake behind my house and back into the lake. I have monitored the lake water temp from time to time and saw highs of around 84 in late Aug. and lows of around 56 in late Feb. I chose not to do that again since I am getting too old to maintain the system. I have had to clean or replace the pump check valve several times, de-scale the heat exchanger about every 3 years and clean the pump motor twice after flood events. I knew how and when to do these things and it was not a great chore but, I could see the next owner of this house having to hire those things done and not liking it at all. The air heat exchanger seemed like the best choice now. In researching the options I saw systems that claimed up to about 24 SEER but they were geo.
I attribute much of the low operating cost to the six-zone system. We only condition those areas of the house we are using.
The Trane system I have now works better and for less operating costs than the geo system I had. It was not cheap but if it lasts 20 years it will outlast me.
What is the winters like there in central TX?
That in combination with your new Variable speed unit, is most likely why your bills are less. I would venture a guess that if your climate is milder like I suspect, A new high end Air unit vs a new Geo there would be no appreciable difference. In which you made the right call going with a less expensive air unit.[/QUOTE]
Our winters are very mild in cen-TX. This winter we have only seen a few nights less than freezing and no days where the temp did not get above freezing. As I write this our temp is 41* and overcast. Forecast is for 35-36 tonight and them warming up into the 60s-70s later in the week. It will be spring here in a week or two.
Our challenge is ac in the summer. Our summer can last six months and for two-three months we can see temps in the high 90's to about 105.
The geo system I had, pumped water from the 400 acre lake behind my house and back into the lake. I have monitored the lake water temp from time to time and saw highs of around 84 in late Aug. and lows of around 56 in late Feb. I chose not to do that again since I am getting too old to maintain the system. I have had to clean or replace the pump check valve several times, de-scale the heat exchanger about every 3 years and clean the pump motor twice after flood events. I knew how and when to do these things and it was not a great chore but, I could see the next owner of this house having to hire those things done and not liking it at all. The air heat exchanger seemed like the best choice now. In researching the options I saw systems that claimed up to about 24 SEER but they were geo.
I attribute much of the low operating cost to the six-zone system. We only condition those areas of the house we are using.
The Trane system I have now works better and for less operating costs than the geo system I had. It was not cheap but if it lasts 20 years it will outlast me.
paulharvey
Veteran Member
Not to hijack the thread, but I live in North central Florida in 1996 Double wide, ~2000 sf. We run AC at 77 or 78 in summer, heat at 69-70 in winter, and pay between $250-325/month. I have an energy audit scheduled for 2/24/15. Has anyone had one of these? Do they offer any real concrete advice or mostly just tell you to upgrade to a newer AC and such? My power company does it for free, but I'm not really expecting thermal imagining or frankly any "actionable" information.
LD1
Epic Contributor
Never had one done, so I cannot help there.
Those 250-325 bills, what is the usage? Electric rates vary ALOT across the country. Usage tells me alot more than cost.
kcflhrc
Veteran Member
We bought our 1970 built 2500 sq ft 2 story 4 bedroom home in September 2013. We put a new Heat Pump in with propane backup when we moved in. Our Honeywell thermostat has a lockout setting for the heat pump which is programmable. I have it set for 30 degrees I believe and I have an outdoor temp sensor wired directly to the thermostat. It is a Heil brand. I'm not overly impressed with the system. Seems to do weird things. Like the heat pump comes on, then shuts off, then the propane comes on for a while, then turns off only after about a minute and the blower continues to run. It only does this when it's around the lockout setting. When it's colder than the lockout then the propane works fine. Just acts real weird right around the lockout temperature. If I had to do it all over again, I would probably just go all electric.
Country Geek
Gold Member
The advantage of a propane backup to a heat pump is that you can run the propane furnace off a consumer-grade generator if the power goes out. That's an important plus if you live in a rural area where ice-storm induced power outages can last a long time.
I had a propane backup furnace installed as part of my geothermal system this past fall. The installer thought I didn't need it and was wasting my money but I wanted it for the ability to easily run off a generator (my house is wired for a generator and the furnace is on the generator panel). He was right in that the system hasn't needed to use the propane backup. Even with temps down into the teens the geothermal heat pump has no problem holding 70 degrees inside with no backup. But they are calling for zero degrees later this week so that will be the real test.
I had a propane backup furnace installed as part of my geothermal system this past fall. The installer thought I didn't need it and was wasting my money but I wanted it for the ability to easily run off a generator (my house is wired for a generator and the furnace is on the generator panel). He was right in that the system hasn't needed to use the propane backup. Even with temps down into the teens the geothermal heat pump has no problem holding 70 degrees inside with no backup. But they are calling for zero degrees later this week so that will be the real test.
LD1
Epic Contributor
Right around lockout temp is finicky. A few things I can think of....
IF the unit is in sunlight, it may warm up the unit (wherever the temp sensor is) just above that lockout. Once it kicks on and air moves, it cools back down to ambient temp and locks out.
Another things is once it is running, lets say its 30.5 degrees outside, the unit is blowing 15 or 20 degree air outside. If that is circulating to getting any bit of that super cold air where the temp sensor is....lockout.
And I am not sure how your system is setup, but alot of propane furnaces continue to run the blower after flame is out. On a timer I believe. You burnt propane and heated up everything including the ductwork. The blower continues to run to extract all that heat and distribute it in the house, instead of letting it slowly cool off in the furnace and ductwork. Especially improtant if you have ductwork in an unheated crawl.
kcflhrc
Veteran Member
Very good info, thank you. The temp sensor is fairly close to the outside unit. The unit doesn't get a lot of sun, it's on the north side of my house so in the winter not much sun there. Full basement so no crawl space and all duct work is in the walls, none in the attic.
In TN, we have a pair of fairly new (2yr old) Rheem variable speed blower, two-stage compressor, high efficiency heat pumps with the Rheem "communicating" thermostats. The thermostats have a variable/programmable "Balance Point" which I at first found to be confusing terminology. It is the lockout temperature below which the compressors are locked out, based on outdoor temperature. Rheem considers the "balance point" to be where the heat pumps can just keep up with the house heat load, running continuously. The thermostats also run the emergency heat strips whenever it deems it appropriate, like when I set a thermostat setpoint that is 2 deg or more away from the room temp, or of course, when the compressors are locked out. I didn't think I was getting any appreciable amount of heating from the compressors when it got down below 32deg. They seemed to run nearly continuously then, and I don't like the compressors running continuously, so I set mine at 32deg. I may now adjust them down a bit based on the excellent discussion in this thread!
You can only get to this setting of the thermostat using the "Installer Setup" menus, so to find it on yours, you should try locating the full install instructions for your thermostats on-line.
Good luck getting yours sorted.
- Jay
You can only get to this setting of the thermostat using the "Installer Setup" menus, so to find it on yours, you should try locating the full install instructions for your thermostats on-line.
Good luck getting yours sorted.
- Jay
LD1
Epic Contributor
Like I have mentioned before, without doing BTU calculations and determining how many watts your system is using, Setting a lockout point is nothing more than a guess. And neither you nor I will know if it is actually helping or not.
And if you have propane for AUX heat, the lockout number at which is most efficient is ever changing. Because electric rates go up, and propane fluctuates. If all electric, you set it once and you are done unless you change some part of the system.
The balance point is the temperature where the heat demand equals the heat pump output. On a conventional HP, it is the temperature where the aux heat would be enabled, not where the compressor is locked out. In dual fuel systems, it is common to cut out the compressor at that temp, due to the problem with defrosting. On units with electric heat, you still get usable heat, at higher efficiency that electric strips, just not enough of it. If you lock out your compressor at that temp, you are losing money.
paul
paul
buickanddeere
Super Member
Ground source geothermal is much different than an air source heat pump.
Air source the available heat from outside air drops rapidly and the energy required to defrost the outside air coil increases when temps drop below freezing.
Obtaining usable heat from an air source as outside temperatures drop to or below 0F maybe possible. Even acceptable if you reside in an area that suffers only one or two brief cold snaps per winter. Operation of any heat pump from November to March with outside air temps near or below 0F is using the heat pump outside of it's intended design curves.
Last edited:
buickanddeere
Super Member
I wonder how many folk believe the HP is warming the house in below freezing temps and are unaware the
Resistance heating is adding another 10-20F to the plenium temperature ?
kcflhrc
Veteran Member
Yep, dual fuel heat pump with a lockout is a completely different animal than an air handler with electric strips. Can you change over a dual fuel system with propane backup to an all electric with heat strips easily? Or is it a completely different inside unit?
Here are some similar links:
