I bought this heat pump to play with in order to see if it would still heat if it is zero degrees outside. It's dual hose and rated 11.2 EER which equates to a 3.3 COP:...
Type: Posts; User: kevin_in_denver
I bought this heat pump to play with in order to see if it would still heat if it is zero degrees outside. It's dual hose and rated 11.2 EER which equates to a 3.3 COP:...
My dual hose unit has very high internal leakage, so a window unit is MUCH better.
Johnny B60,
I sincerely apologize, first I hijacked your thread and then I killed it.
Here's a positive review of a Coolerado that was just posted at Jetson Green:
"I recently installed a...
JimJ,
Thanks for more info. Interesting to hear that EC's are sometimes piggybacked on a conventional ducted AC system. That means, of course, that the ducts are probably 5X too small. I've...
H.E., I admit it's starry-eyed optimism, but it's an easy back-of-the-envelope calculation. On a hot day, figure maybe 20 million compressors, times what, an average 4kw each..... replaced by a...
Commercial kitchen makeup air is often passed through a swamp cooler, even in humid environments. Better than nothing, since conventional AC is impractical for that much air volume.
If...
A rather unsatisfying discussion. Similar to what I'm finding as far as trying to find a good swamp cooler contractor.
I think evap cooling is being treated as the "bastard stepchild" of the...
Extra credit problem on ME PE test:
For a given system at steady state, how do you calculate the maximum theoretical EER in terms of the Carnot efficiency?
[Edited by kevin_in_Denver on...
Brent,
I have considered geothermal, but the load is so darn small, and the first geothermal btu costs so darn much.
I'm going to run a cost simulation with something like Energy-10, which...
Brent,
I definitely understand what you're saying is the buyers perceptions, and I do want these to be upscale.
But when heat pumps are achieving 21 SEER, and the townhomes have such a low...
Thanks for reminding me about the domestic hot water. Solar would be the primary source, so electric resistance may make sense.
It almost seems like change in this industry is happening fast...
No A/C in the baths is fine. End units have 3 bds., interior units have 2 bds. At 9,000 btu/hr, these are a little big for a bedroom, the above suggestion of a vertical PTHP servicing two bedrooms...
Wyounger,
Thanks for more well-thought out info. I wasn't considering a central split heat pump because I didn't think there were any that ran efficiently below 30F. I'll research that some...
Thanks for well-thought out information, Johnsp.
Fujitsu now has 21 SEER mini split units, which I guess operate at a COP of over 5. Apparently they don't need strip heaters for low outdoor...
Dual fuel is looking very attractive to me also. I'd like to include them in a few new homes I'm building.
These units don't seem to be on anyone's radar in this area.
As installers/servicers,...
In the 80's there were a few systems built that used ammonia absorption cycle machines from an outfit called Arkla. They weren't very successful. LiBr has some potential, and is supposedly being...
The water source systems just look too complicated to me. Since my heat loads are very small, I think I'll just try a couple conventional PTACs. Will I be getting a 3.0+ COP?
There was no cooling in the mechanical room. I forgot to look for attic fans. There was no swamp cooler, but I'm sure a small one will eventually be added by the new occupants.
This link shows a...
Thanks, John and everyone else for your help.
Mark,
Take a look at the zero energy homes that H4H is building:
http://www.worldchanging.com/archives/003529.html
I toured this home last...
As a home developer looking at low-energy homes, I like the cost, efficiency, and flexibility of PTACs instead of central ducted HVAC.
I'm a little scared of the cost of resistance heat during...
I used to have a Glowcore, and they do need maintenance service calls more often than conventional boilers. It has relatively small openings for the combustion gases to pass through, and they need...
Has anyone heard of builders installing PTAC's in new homes?
As I see it here are a few of the issues:
1. The cost of gas has now officially made air-to-air heat pumps the cheapest way to...
Thanks John, I'm surprised I never heard about them.
I'm a developer interested in innovation, and I'm kicking around some HVAC ideas.
This new portable A/C and heat pump caught my attention because it could potentially eliminate my HVAC sub, as...
Mfree, don't forget to check out the demand rates. Even on a smallish house, it averages out to around $0.04/kwh
I'm working on a similar analysis for a mountain home in Colorado.
Electric resistance heat is looking like it may be my best option primarily because of Xcel Energy's "Residential Demand" rate...