![]() |
![]() |
#11 | |
Supreme EcoRenovator
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,004
Thanks: 303
Thanked 723 Times in 534 Posts
|
![]() Quote:
-AC
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker... |
|
![]() |
![]() |
The Following User Says Thank You to AC_Hacker For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#12 |
Master EcoRenovator
Join Date: Mar 2014
Location: Florissant, Colorado
Posts: 599
Thanks: 814
Thanked 59 Times in 55 Posts
|
![]() Try to decide if insulation over shallow loop field is worth the cost.
|
![]() |
![]() |
![]() |
#13 |
Master EcoRenovator
Join Date: Mar 2014
Location: Florissant, Colorado
Posts: 599
Thanks: 814
Thanked 59 Times in 55 Posts
|
![]() Another large Solar heated slinky loop system 5800ft2 in Alaska,
some videos & nice diagram: Ground Source Heat Pump and Solar Thermal | Cold Climate Housing Research Center |
![]() |
![]() |
![]() |
#14 |
Lurking Renovator
Join Date: Jun 2009
Posts: 24
Thanks: 3
Thanked 5 Times in 5 Posts
|
![]() Afaik, insulating above a shallow field would be hugely detrimental to the field as the sun is greatly responsible for reheating the ground.
Additionally, if you are considering doing a field in series, be sure to have the panels before it returns to the field. Most heat pumps have a limit on the temperature of the incoming ground loop of around 110. I am not sure why this is, but I've seen it on the specs of every heat pump I've looked at. |
![]() |
![]() |
The Following User Says Thank You to Blue Bomber Man For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#15 | |
Supreme EcoRenovator
|
![]() Quote:
|
|
![]() |
![]() |
The Following User Says Thank You to jeff5may For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#16 |
Supreme EcoRenovator
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,004
Thanks: 303
Thanked 723 Times in 534 Posts
|
![]() I think it's one of those inconvenient Physics limitations, concerning the characteristics of the refrigerant.
-AC
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker... |
![]() |
![]() |
The Following User Says Thank You to AC_Hacker For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#17 |
Supreme EcoRenovator
Join Date: Oct 2008
Location: Austin, TX
Posts: 1,154
Thanks: 14
Thanked 257 Times in 241 Posts
|
![]() Once the temperature goes that high, it would make more sense to bypass the heat pump in which case it's a moot point. The real limit is how high the suction pressure can go without overloading the compressor.
__________________
To my surprise, shortly after Naomi Wu gave me a bit of fame for making good use of solar power, Allie Moore got really jealous of her... |
![]() |
![]() |
The Following User Says Thank You to NiHaoMike For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#18 |
Less usage=Cheaper bills
Join Date: Nov 2010
Location: Minneapolis, MN
Posts: 939
Thanks: 41
Thanked 116 Times in 90 Posts
|
![]() I agree. If you have access to 110+ degree water, it would use less energy to just pump it through a traditional hydronic heating setup.
|
![]() |
![]() |
The Following User Says Thank You to MN Renovator For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#19 | |
Supreme EcoRenovator
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,004
Thanks: 303
Thanked 723 Times in 534 Posts
|
![]() Quote:
This is exactly the place where traditional thinking fails in low temperature heating installations like solar, geothermal, etc. Very few hydronic installations (Daox excepted) have built-in efficiency to take advantage of feed temps on the 110 range (and lower). Vlad's house works with 12" spacing & aluminum heat spreaders because he heats all the floor area, has rigorously reduced infiltration, and put in very good insulation from the start. With three floor levels, his floor area/house volume ratio is fairly high, which favors radiation. Also because his house is large and vaguely tends toward a cubic form, his external area/house volume ratio is relatively low so his house favors lower skin losses. Did I mention his floor is topped with porcelain tiles, which has a very high U-value? Lastly, he lives in the Vancouver Canada area and the HDD are not as high as they are in a place like Minneapolis, MN. Vlad reported feed temps in the 112 range when the weather got really awful. Of course, awful in Vancouver could be a relief in a Minneapolis winter, or a Colorado winter at high elevation. -AC
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker... |
|
![]() |
![]() |
The Following User Says Thank You to AC_Hacker For This Useful Post: | buffalobillpatrick ![]() |
![]() |
#20 | |
Supreme EcoRenovator
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,004
Thanks: 303
Thanked 723 Times in 534 Posts
|
![]() Quote:
What do you see when you compare the available solar gain of the site in UK with your site located 4000 feet up in Colorado? Does that comparison make sense? -AC
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker... |
|
![]() |
![]() |
The Following User Says Thank You to AC_Hacker For This Useful Post: | buffalobillpatrick ![]() |
![]() |
|
|