Hong: what is your zip code? The Northwest covers a pretty wide range of climates.

Tks. For the fast help. My zip code is 99019, Liberty Lake, Washington. Hong

Tks. My zip code is 99019, Liberty Lake, Washington. Hong

Hong,

There is a sticky thread here for new members with questions about their system. It lists a few questions we need answered in order to help you.

http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/aft/76608/afv/topic/afnp/79135/Default.aspx

Hi Kurt, tks. for the reply. 

1) Where you live:  Spokane, Washington.
2) Heat loss/gain calculations for your home:  I do not know how to calculate this.  it is a new construction meeting next year's new code.  49R on the ceiling and 21R on the wall
3) Brand, size (model), age and type of heat pump:  ClimateMaster Tranquility 27 2-stage, 5 ton, Model # TTV064AGC01ALKS
4) Type of loop field (open/closed/vertical/horizontal) size and design parameters: 5 200' deep vertical loops.  Each is supposed to produce one ton of BTU
5) Average cost/Kwh of electricity and consumption:  $0.08 to $0.09/Kwh depending on the usage.  Underneath is the actual meter reading and the Kwh usage since I moved into the new house.
6) Entering and leaving air temperatures (EAT, LAT) measured immediately upstream and downstream of the heatpump:  I do not know how to do this. 
7) Entering and leaving water temperatures (EWT, LWT) measured at the geo system:  I do not know how to do this.
8) Percent of load to be covered by geo and balance point:  I do not know.
9) Installer's assessment of your systems operation.:  he said that it is OK.  but he did say something that I believe it is incorrect.  that is Stage 1 heat will generate 55% and the Stage 2 will generate up to 100% (including both stages).  The unit say loudly that the Stage 1 generate about 67% before Stage 2 kicks in.   But most of the time even when the thermostats temp still satisfy the requested temp, both stages heat got turned on, then maybe later Stage 2 got turned off, then Stage 1 got turned off.  But after about 10 mins, both stages got turned on again and the cycle begins. 
10) Projected operating costs, actual operating cost and previous heating and cooling costs:  this is a new house and we just begin to live in.  no comparison.  but with this Geo system I am using just about the same cost as the neighbors that uses forced air system. 

Huang Avista Electric Meter Analysis
Date	Days between Reading		Meter Read (KWH)	Actual Usage (KWH)	Daily     Usage (KWH/day)
10/26/10			768
11/24/10	29		3245	2477	85.41
12/27/10	33		7220	3975	120.45
01/06/11	10		8568	1348	134.80
01/07/11	1		8710	142	142.00
01/08/11	1		8856	146	146.00
01/09/11	1		8990	134	134.00
01/10/11	1		9127	137	137.00
01/11/11	1		9273	146	146.00
01/12/11	1		9418	145	145.00
01/13/11	1		9526	108	108.00
01/14/11	1		9621	95	95.00
01/15/11	1		9720	99	99.00
01/16/11	1		9814	94	94.00
01/17/11	1		9912	98	98.00
01/18/11	1		10013	101	101.00

Is it keeping you warm?

Your unit is rated for 5 tons cooling. Heating output is more like 48kBTU which, at a COP of 3.5 is 4kW/hr running flat out. That's 90-100 kWh per day which would account for your usage.

Doesn't look like you have an aux electrical coil, do you?

That's a huge house in a higher-than-average heating area. What happened on Jan 14-17? Did you leave for the weekend or was it because the temperature came way up during that time?

The CM Tranquility 27 model TT064 does have a 5 ton rated heating capacity, but that's at 50 F entering water temperature (EWT), as shown in their online documentation, page 67 of this:

http://www.climatemaster.com/share/Res_All_Products_CLM/Section_3_TT27.pdf

At only 30 EWT the heating capacity is only 4 tons.

You have daily readings since 7 Jan. I took a quick look at Spokane Airport temps this month

warm on the 7th, near normal 8th, cool 9th, very very cold 10th, 11th, normal on 12th, very very mild since then, but getting ready to cool back down. Average temp for this time of year is upper 20s.

The initial read on 10/26 - 768 kwh was for how many days? Reason I ask is to try to determine base load for house - net of heating or cooling, and October is often a good month to figure that. I would need the days you lived in the home

A $14 digital meat thermometer from Walmart is good for entering or leaving air temps. If there is a Petsmart outlet nearby $10 gets you a Topfin aquarium thermometer - same idea, possibly more accurate, 5 second update times.

for water temps tape the thermometer probe tip to a metal part of the loop plumbing, such as the square bronze fitting right outside the cabinet. Fold a small piece of aluminum foil a couple times, partly wrap the end of the probe in foil and tape the combination to metal. Insulate that with a rag and note readings when they stabilize.

Installer should have done a load calculation before selecting the unit's capacity - ask to see it.

Looking at more Spokane weather data, December was only about 15% colder (1096 vs 948 degree days) but your whole house kwh usage nearly doubled - were you fully moved in between 10/26 and 11/24?

I suspect some aux strip usage - the trick will be to try to find out why.

Tks. a million for all these great help here. Let me reply each with your text included:

Is it keeping you warm?: A: yes it does keep the house at the target temp. Upstairs at 70F and basement at 69F 24/7 now. In December, which is the first month after we moved in (we moved in during the Thanksgiving holidays). I followed Honeywell thermostat's 4 different temp setting and the huge change between sleep and day time probably kicked start the Aux heat and I didn't notice (at sleep). I changed the setting right after the first of January

Your unit is rated for 5 tons cooling. Heating output is more like 48kBTU which, at a COP of 3.5 is 4kW/hr running flat out. That's 90-100 kWh per day which would account for your usage.: Q: are you saying that my Geo heat pump is marginally sufficient for my house and need to use 90 to 100Kwh every day without considering how high or low the temp?

Doesn't look like you have an aux electrical coil, do you? A: yes there is an Aux electrical coil for emergency heating. It also can heat the water during the summer but is not connected yet due to the winter season. is this correct? I have 2 50 gallon tanks and I am only using one (electric) now.

That's a huge house in a higher-than-average heating area. What happened on Jan 14-17? Did you leave for the weekend or was it because the temperature came way up during that time? A: the temperature went up to the 40's during those days.

Hi Dick, tks. for the help here.

The CM Tranquility 27 model TT064 does have a 5 ton rated heating capacity, but that's at 50 F entering water temperature (EWT), as shown in their online documentation, page 67 of this:

http://www.climatemaster.com/share/Res_All_Products_CLM/Section_3_TT27.pdf

At only 30 EWT the heating capacity is only 4 tons.: Q: are you saying that the EWT at 30 is the water temp from outside? I thought for heating purpose, the 5 200' deep vertical pipes has the constant temp. of about 55 F. What does this 30 mean? tks.

Hong

Hi Kurt,

tks. for your help!

You have daily readings since 7 Jan. I took a quick look at Spokane Airport temps this month

warm on the 7th, near normal 8th, cool 9th, very very cold 10th, 11th, normal on 12th, very very mild since then, but getting ready to cool back down. Average temp for this time of year is upper 20s.: A: tks. for the checking. you are correct.

The initial read on 10/26 - 768 kwh was for how many days?A: it is for the month of Oct. But it is not a good indicator as in October the construction is still going on. The Geo was in the testing mode and there is no way of knowing what is for Geo and what for construction usage. Reason I ask is to try to determine base load for house - net of heating or cooling, and October is often a good month to figure that. I would need the days you lived in the home: A: We did not move into this new house until the Thanksgiving day.

A $14 digital meat thermometer from Walmart is good for entering or leaving air temps. If there is a Petsmart outlet nearby $10 gets you a Topfin aquarium thermometer - same idea, possibly more accurate, 5 second update times.: A: tks. I will go buy one.

for water temps(Q: why do we need to test the water temp? ) tape the thermometer probe tip to a metal part of the loop plumbing, such as the square bronze fitting right outside the cabinet ( Q: what cabinet? the Tranquility 27? and where? please help me with a bit more advice on the specific location. Too bad the site does not allow me to upload pictures) . Fold a small piece of aluminum foil a couple times, partly wrap the end of the probe in foil and tape the combination to metal. Insulate that with a rag and note readings when they stabilize.

Installer should have done a load calculation before selecting the unit's capacity - ask to see it. A: I will. tks.

Looking at more Spokane weather data, December was only about 15% colder (1096 vs 948 degree days) but your whole house kwh usage nearly doubled - were you fully moved in between 10/26 and 11/24? A: we started moving in right around Nov. 24th.

I suspect some aux strip usage - the trick will be to try to find out why? A: I love to find out why but with my observation it seems very rare that the Aux heat is turned on unless the requested temp is 6 to 7 degrees above the existing temp.

What does this 30 mean?

It's just a standard rating condition. The Standard rating condition for the heating side is an EWT of 32F. It doesn't have anything to do with what you are actually seeing. Assuming your EWT is higher you will have higher performance.

Hi Kurt and the other engineers, tks for the quick response. I have replied to your questions after your comment/questions. Any further help? tks. a lot. Hong

Q: why do we need to test the water temp?

The water temperatures and the flow rates are measures of the heat available to the heat pump. If you think of the temperatures as a gradient, the work the heat pump has to do is to pick up heat at the low temperature (from the loop) and push it uphill (to the air coming out the vents). The colder the water or the warmer the air, the more work (electrical power consumption) needs to be done. That data helps make some determinations as to how efficiently the heat pump is operating.

People have also been trying to figure out how much electricity is being used for your heating and for other purposes. Your electrical readings give the total amount, but the trick is figuring out how much your particular home uses for heating versus lighting, hot water, cooking, etc. With what you said in the other thread about observing a 20A total draw when the heat was full on, that would be consistent with your heat pump running on full. Since the units should be properly sized to handle near peak loads (the coldest days), that would also fit since you experienced some pretty cold weather during this time.

Without knowing what auxiliary heat element is installed in your furnace (if any), it is hard to say if you can detect aux heat usage from the summary electrical data. If you had the smallest element, it might sneak some burn time in there among the kilowatts used, but if you had the large one, you'd probably see more usage than you do. It uses on the order of 20 kW, or upwards of 80A. Would you notice that on your meter?

My guess is that what you are seeing is pretty much the usage of your heat pump during cold weather. You need the operating parameters to have a service engineer determine if it is operating at peak efficiency and whether your ground loop is performing well. You saw that when the weather warmed up, your electrical usage decreased, which is appropriate to the heat losses from your home. Appropriate, but without knowing your home heat-loss design parameters or an on-site energy audit, one can't say whether it is optimized or not. That's a big home. If you assume that 50kWh/day go to hot water and other uses, and normal heat pump operation, you are right in there at about 5 BTU/SF/HDD with a bit more at the warmer temps which is another clue that you don't have a big problem with using resistance heat (aux).

That being said, there might be some improvements you can do to reduce the heat loss from your home. If your heat pump is operating near capacity for whatever reason, reducing your home's needs (particularly during the coldest weather) can help ensure that you stay in the "sweet spot" for the furnace.

Posted By ICFHybrid on 21 Jan 2011 11:01 AM

If you assume that 50kWh/day go to hot water and other uses ...

Hmm... 50 kWh per day base load?

...that's a lotta grow lights!

Looby

...that's a lotta grow lights!

Nintendo. ;-)

At 5500 sf, that's a pretty big house. They tend to attract the little here, little there energy eaters.

Not too long ago I got rid of one of the 2500 sf architect-designed ranch homes from 1950. Gas furnace and everything else electric. 60kWh/day.

Posted By ICFHybrid on 21 Jan 2011 08:14 PM
... 2500 sf architect-designed ranch homes from 1950.
Gas furnace and everything else electric. 60kWh/day.

Where was that? ...Murmansk?

We just finished our second complete year on geo, in
a 57 year old, 2200 sf ranch -- on a heavily wooded
lot with near-zero solar gain (Philly 'burbs).

Two-year average (incl. 2 cold winters) = 35 kWh/day
for HVAC, HW, cooking, lighting, absolutely everything.
System = 3-ton WF Envision NDV038, closed, vertical
(retrofitted to replace oil-fired hot water baseboard).

BTW, shoulder season base load is about 11 kWh/day.

Where was that? ...Murmansk?

Ha Ha. Believe it or not it was the Pacific Northwest. A mild maritime climate.

My wife and I installed the Climate Master Tranquility 27 in 2011. 

It seemed to perform well for a period, but then degraded.  Freon was added twice.  This year, it was determined that the freon was leaking from the coil.  Even though I have a parts and labor warranty, I'll still be charged over $1,000 total to diagnose ad repair the unit as the warranty says that  they only provide a "labor allowance:"  Two lessons learned:

1. Watch the performance of the unit over time.  If it is degrading, check the Freon.  It shouldn't require Freon replacement in the closed unit.
2. Consider that the cost of the extended parts and labor warranty does not cover the full cost of labor to make any repair.
   

Bottom line,  we haven't yet seen any savings from the unit.  It runs continuously, and can't seem to bring the temp in the winter above 61 degrees.  And with the exorbitant maintenance costs, I couldn't possibly recommend this unit.

Hey, vk,
Like you, I've seen some great performance from my geomax climate master 4 ton on a 2100 sq ft house. I posted my electric bills (cost of just hvac) on my wel site. WEL0487

Looking over the year, the average is $50 per month with a rate of about 11 c/kWh.

Previous owners had oil baseboard and their bils were between $300 and $500 every month summer or winter for oil.

The other day at work, I overheard someone saying their electric bill was $400 last month. Mine was $190 if I include $90 for heat and about $100 base usage.
I said, "wow! I don't know what I'd do if I got an electric bill for $400."
She asked what mine was.
I said, "$190".
She said, "yes, but that's only your electric. What was gas?"
Me:"no gas or oil, all electric."
Her:"WOW!"
I'm also in SE PA.