Posted By Dana1 on 25 Jun 2012 05:56 PM

As field & lab testing under the Northwest Ductless Pilot program has shown (http://neea.org/research/reports/E12-237_Combined.pdf ) most manufacturers' unit meet, and often exceed the rated performance, even when they hit their HSPF numbers in the lab. But HSPF is only the half of it- with any air-source heat pump, how well -tweaked the control algorithms work for YOUR climate and YOUR load makes or breaks it.

Posted By sbeausol on 22 Jun 2012 11:23 AM
This is a follow up to a previous thread located here: http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/aft/80100/afv/topic/Default.aspx


a 2100 sqft ranch in Essex MA with 2.6 acres of land

can be horizontlly trenched for GT say a single 4ft wide, three pipe, x 240 ft long x 7ft low depth and over back at 5ft (excavators will understand) - over-under / out and back with 500 ft x 3/4 coils, IF NO ROCKS NOR SHALE, or you should place in clay -/ little sand/ around piping, avoiding pipe leakage-

Any Basement?
for considering maximum comforts:
half that basaement in a calc works well:
1400 cfm on high heating, (a 3.1/2 "ton") but only about 2.1/2 air changes , ducted properly , on cooling (I liive zone 5.1/2+, had 41 deg 2 weeks ago, 10% cooler than Cleveland ) - This is like what no Mini will  near 80% do for total comfort. An  under-ducted home is closer to Mini-Comforts with Mini's../, UNLESS open Mezz, etc, just 2 or three closed/day-opened  rooms are planned, and 65% to 85% spot comforts are acceptable.

Do you have any n-gas for back-up?. Note: Most "3-Ton" rated GT are with only a 2.1/2 ton compressor.
See your manual J heat load and compare to the AirHP (and MINI's) out puts of "3-rated-'tons' " at 12F and 7F and decide.
Efficiency trade offs, ---
do you have a super little car? OR did you enjoy a loss of 100 to 400 monthly on the ' Leather'? If peace of mind attitudinally extends profits above that, then we enjoy 'Leather'.

DO PUT MORE IN THE BUILDING AS IS NECESSARY and resale values are then higher, as well.
But then--- 
 only decide on form and function asking ABOUT BOTH the HVAC WITH HOT WATER HEATING in every question to the contractor.
ADD th HW SYSTEM COSTS to all equating.

"How will I fair in an overall "controller's" view of satisfying a 7yr ROI and affording necessary HW+HVAC comforts and efficiencies?"

If you want a 2 or 3-Staging unit, the heat load may be avoided by sizing for INSTANT HW of using a 3.-3.1/4 ton compressor system for recovery like that of a gas HW heater. Then  the staging, like individual Mini's , efficiently ONLY MATCHES LOADS, from 1.1/2 Tons on up, or if all you want is a DeSuperheating HW generator for the tax credits and admittedly significant HW, a 2-Staging "3-Ton" w/ an efficient 2.1/2-ton compressor, will start a first stage closer to just one ton.

Perhaps still ask to know:
How do I adequately recover heat in Cooling modes while simultaneously heating water larger than just a desuperheater?

 ~~~~~~~~~~~~~~~~~~~~~~
at $19k, which seems high ...quote- and nearer 2-staging GT comparable 2.1/2 ton unit. an extra zone dampening, and a 3-Ton Loop, etc. with HW ~ ?under 27000 (tanks, plumbing, all) net @ $18,900. less Ut'y Rebbates???

2100 ranch? nder $8000 ducting and setting, $8000-10000 Loop and Pump, 3-Ton of any 2012 Energy Star assymptotic efficiencies all have to have--- @ $4500+ hook up...  and   add HW SYTEM(s) in GT Credits as are for the Qualified owner.
Horizontal excavators - one ditch, may be saving 2500 more, if a 3ft pile of dirt for a year can settle.

AirHP +++ HW SYstems , then not in credits  vs. HW+HVAC  "in credit"...= ? x .7 and less Ut'y Credited Rebates...@ ?


YOU MAY FIND A 2-TON RATED , DESUPERHEATER INSTALLS (-2.1/2TON - 2-STAGING) just more reasonable , but ON A 3-TON LOOP w/ HW production, etc. to maximize a total return of dollars in 10 years, anyways.
By DOING-  a productive energy audit -  AFTER BUILDING TIGHTENING CALCLATIONS, even in 10-below weather.
2- 2.1/2ton GT super-compares to any 3-Ton 20-SEER / both appropriately installed.

Bryant Systems?


Geo company around my area?       [email protected]     www.groundloop.com  will know , all though not local




Bryant system runs down to --- seen 3-deg F , 3- ton 14 SEER 1999,  fine -2011 working still, then removed in remodel.

rarely low zone 5, heating strips as a backup.


www.GEOPros.com

Posted By Dana1 on 25 Jun 2012 05:56 PM
"While I have a healthy skepticism of SEER, EER and HSPF "up to" ratings, I'm not quite as disdainful as Dana. They do represent AHRI certified values, which means that if a system is installed and charged per manufacturer instructions and connected to decent ductwork it oughta produce 80-90% of lab rated performance...kinda like EPA mpg ratings...if you drive conservatively, you can attain the MPG ratings."

It's the 80-90% of lab-rated performance even when it's done most-right that makes me shy away from ducted statements on efficiency. There are fewer ways to screw up ductless systems in ways that would peel 10-20% off the system performance. To be fair, even 80% of a 13.0 HSPF performance is a VERY good 10.5 "as installed" HSPF.

But the $20K price tag is a bit daunting. I'm sure there are many ways to spend $20K on improving the efficiency of the house.

As field & lab testing under the Northwest Ductless Pilot program has shown (http://neea.org/research/reports/E12-237_Combined.pdf ) most manufacturers' unit meet, and often exceed the rated performance, even when they hit their HSPF numbers in the lab. But HSPF is only the half of it- with any air-source heat pump, how well -tweaked the control algorithms work for YOUR climate and YOUR load makes or breaks it.

Posted By sbeausol on 31 Jul 2012 11:43 AM
Finally got my first Geo quote which includes the following:
48,000 BTU heating, 23,000 BTU Cooling
Domestic hot water assist, Two zones, air handler, water furnace series 5: $16k
4 horizontal loops: $7k
Ductwork: $12k
Equipment Installation: $14k
Discount: $4k
TOTAL: $46k

At first glance, it seems high, but at least it's not $100k... any thoughts?