I need an expert

[Steve Bailey]

We moved into a new, custom-built house, 2,400 square feet, in October. We have three zones, two have 2,000-ton ClimateMaster Tranquility systems and one has a 5,000-ton system. All have Carrier air handlers.
We live on the Eastern Shore of Maryland and our house has a lot of glass, but we're shocked that we've averaged about 100 kilowatt hours a day all winter, and that's keeping one zone all but inactive and the others at 67 or 68 degrees.
We've had to have the installer out several times with the heat pumps have quit generating heat. We suspect that there may be problems with the way our system was installed.
Does anyone know an HVAC guru who could come to our house, assess our system and make whatever adjustments might be needed? Possibly someone in Baltimore or Washington??
Please email me at
Thanks.

No email addresses in post, Please put it in your profile, Thank you.

[bmathews]

9000 tons? I'm not familiar with Climatemaster. But I will assume you mean 1-5 ton and 2-2 tons?

[ndiglo]

Water source heat pumps? 410a?
What are the model numbers? there are built in error dignostics on the boards. CXM (tan) or DXM (green).
What does the installer tells you about the failure? Should be very easy to retrieve the fault code. Water loop problem?

[beenthere]

9 tons sounds a bit much for 2400 sq ft.

Sounds like the home was built from canvas.

[bmathews]

9 tons sounds a bit much for 2400 sq ft.

Sounds like the home was built from canvas.

He said there was a lot of glass, maybe it's all glass?

[WhoIsThat?]

For a house 80' x 30' x 30', surface area ~12,000 sq. ft., what kind of R value would you need to get this kind of performance? 3" of dead air should give ~18.

All winter for you is 35℉ x 90 days = ~3200 HDD?

[Steve Bailey]

The house has six sets of 8-foot-high sliding glass doors facing west, catching the full brunt of most weather coming off the Chesapeake. There are three other sets of sliding glass doors, plus a lot of clerstory and other large windows. That's why we have a total of nine ton for a 2,400-square-foot house (which the county figures is 2,700 square feet anyway).

The units are ClimateMaster Tranquility 27 split units. Water in a closed loop involving eight wells. The installer's man says that the error message is that one of the unit freezes. He says it's because it's the zone that we have shut off and unused, so the thermostat was set at 55. He said that was too low and to keep it no lower than 62 or 64.

Thanks for all the replies, but I really want to get someone who knows what they're doing out here to look at the system. I'm not a DIYer -- I'm a pay-thru-the-noser when it comes to this stuff.

[beenthere]

Search for

Heatpumpguru. On this site.

He may serve your are.

Since this is Geo, I moved it to the geo forum, where you may get more responses/help from Geo contractors.

[geodean]

Steve,

do you know how many feet of bore hole you have in the eight wells?

You need to ask the installer if the back up heat has been running.

Heat pumps use roughly 1KW per ton. If yours are running 12 hours a day ( not too unlikely with the cold weather ) , you would use around 100 KWH per day.

If the unit is shutting off, it usually means the EWT ( entering water temp, from the ground ) has dropped too low.

Ask your installer what the EWT is after the units have been running for awhile.

Do all of the heat pumps share all of the bore holes?

[geodean]

The installer's man says that the error message is that one of the unit freezes. He says it's because it's the zone that we have shut off and unused, so the thermostat was set at 55. He said that was too low and to keep it no lower than 62 or 64.

The guy who told you this is lacking a basic understanding of how heat pumps work. At this point I would not believe any thing he says.

I hope you can find a qualified second opinion.

[WhoIsThat?]

How much would the OP have to spend to buy one instrument that would go a long way to finding the root cause of the problem, if there is a problem?
Preventing a continuing hassle has got be worth something.

If there is such an instrument, what would it be? This is either for the OP to buy and use, or for the OP to tell the tech. to use.

[beenthere]

He needs a company/tech that knows Geo systems.

If I went out and bought an MRI machine, that wouldn't mean that I would know what it was telling when I used it.

[geodean]

There is no one tool or instrument that will diagnose a geo system.

If you had a pressure gauge and thermometer that would read through p/t ports ( assuming that p/t ports are installed ), you can tell a lot about the system.

The first item to check is the aux heat. If it is running a lot, the KWH used will increase dramatically .

[WhoIsThat?]

http://en.wikipedia.org/wiki/Geothermal_exchange_heat_pump

"When comparing a geothermal system to an ordinary system, a homeowner can save anywhere from 30% to 70% annually on utilities."

"Some electric companies will offer special rates to customers who install geothermal systems for heating/cooling their building"

http://www.google.com/search?client=safari&rls=en-us&q=%22Geothermal+Heat+Pump+Consortium%22&ie=UTF-8&oe=UTF-8

I hope some of this info is of use. . .

[DAVE W]

did the tech check the alarm code if it is a freeze code 4 check to see if the low temp. jumper was cut for use with antifreeze in the system this will enable operation of the heat pump down to 10F make sure anti freeze was installed in the system or damage will occure. note climatemaster has been having problems with the freezesensors and are working on the problem i talked to the rep. last week. dave

[Steve Bailey]

Thanks for trying to help. To answer some of your questions, I don't know how many feet of bore hole I have in the eight wells?

The back up heat has not been running because I had the installer alter the thermostats so that the aux. heat doesn't come on automatically. The only way the elec. back up comes on is if we switch to "emer heat" on the thermostat.

Heat pumps use roughly 1KW per ton. If yours are running 12 hours a day ( not too unlikely with the cold weather ) , you would use around 100 KWH per day.

I think the installer said that the EWT was 49 or 50 degrees after the units have been running a while.

I don't know whether the heat pump share all the of the bore holes.

I try to find out the things I don't know later this week.

Thanks again.

[bc3141]

If the design load really is in the 9-ton range, 80-100kWh per day is not out of the question, especially this January.

Is the 100kWh for just the heat pump, or the whole house?

[marauderx]

What are your in & out temperatures for the system? The heat pumps may be unable to extract enough heat based on your needs & the temperatures you are facing.

Also the Geoexchange forums might be of some help.

[junkhound]

Back of envelope calculations assuming 600 sq ft of windward windows 'rated' R4. Windward can reduce that to R=2 easily. Thus the windows alone could be eating as much as 20,000 BTUs/hr. Roof and ceiling at R30 and 5400 sq feet, add in infiltration, another 10-12K , if windward increases infiltration say a total of 40,000 BTU/hr at 30F TD -- HO should be able to get contractors exact numbers for this for a custom home, but most contractors do not derate glass for continuous wind!.

For 100 kWhrs daily, using rule of thumb that HP is 1/2 household load in winter assuming HWH is electric, HP equates out to a COP of 'only' 5.6 .

I'd say the OP has a darned good HP install and that one has to pay for an expansive view of windward water!

[skippedover]

You say you've got Tranquility 2-stage units with Carrier air handlers. That's a great combination with good efficiencies BUT, we've had several of the Tranquilities with leaks in the water water coil. We changed 2-units in warranty (change the whole cube) and I suspect we've now got another one (sold under the Bryant flag) that we'll have to replace the coil. I think they've been having little problem with coil production due to the huge increase in units being shipped. I'm glad someone is increasing their business in this lousy economy at least. When they get a 'Freeze Protection' alarm/lock-out, it can be an under charge of refrigerant. An uniformed tech would think the alarm relates to water temperature due to flow problems but it is water temperature being protected but it's due to an excessively cold evaporator and that's being caused by low refrigerant charge if my experience is any help here.

As to the operating costs, I'd recommend you compare yours to those who are heating with oil or gas in comparable homes with comparable exposure and living style. That could help put your electrical use into perspective.

[WhoIsThat?]

Good signature line.

[carm1575]

You say you are using 100 Kwh/day. Is this for your whole house or just for the 3 geos? I live in Ottawa, Canada (much colder winter) and we use about 120 Kwh/day in winter with a 5 ton geo unit. This is is for the whole house - not just the geo.

[bmac]

These guys might be able to help you, if their in your area. They do good work.

http://www.wheatandsons.com/serv-heating.php