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Aranarth
join:2011-11-04
Stanwood, MI

Aranarth to cdru

Member

to cdru

Re: Do Air Conditioners and Heat Pumps cool equally well?

said by cdru:

said by Jack_in_VA:

The EPA has been considering outlawing “pump and dump” open loop geothermal heat pumps, but using open loops that return the water back into the earth via an injection well will most likely continue to be acceptable practice.

I'd have to ask around, but I believe even injection wells are frowned upon.

There was an article in the farm bureau newspaper talking about that. The issue is that when you inject directly into the water table if it is not filtered by the land you can contaminate the ground water directly. This is also a big issues with irrigation wells that are not properly capped. Improperly capped wells was the main focus of the article.

tstolze
Premium Member
join:2003-08-08
O Fallon, MO

tstolze to Ken

Premium Member

to Ken

said by Ken See Profile
It is an option. It's more expensive to install, more expensive to operate, and doesn't help keep the pond full. Open loop is cheaper to install, cheaper to operate, and keeps the pond full.

Although more efficient due to steady water temperatures, the cost of running a well pump and pump maintenance/replacement often put the operation cost higher than a closed loop system.

cdru
Go Colts
MVM
join:2003-05-14
Fort Wayne, IN

cdru

MVM

said by tstolze:

Although more efficient due to steady water temperatures, the cost of running a well pump and pump maintenance/replacement often put the operation cost higher than a closed loop system.

And now the discussion has gone full circle.

boogi man
join:2001-11-13
Jacksonville, FL

boogi man to Ken

Member

to Ken
how far away from the pond are you? i'm really curious about the particulars of your install that would make a CL system in a pond more expensive than a well. generally the pond, lake stream option is one of the cheapest as it requires very little trenching/digging comparatively.
boogi man

boogi man to tstolze

Member

to tstolze
the thing with a CL system in a body of water is that it's temp may not swing all that far depending on depth clarity of water and other local factors.
tomupnorth
join:2005-01-14
UpperMidwest

tomupnorth to cdru

Member

to cdru
said by cdru:

And now the discussion has gone full circle.

Not to mention of course, completely off-topic!

Ken
MVM
join:2003-06-16
Markle, IN

Ken to boogi man

MVM

to boogi man
said by boogi man:

how far away from the pond are you? i'm really curious about the particulars of your install that would make a CL system in a pond more expensive than a well. generally the pond, lake stream option is one of the cheapest as it requires very little trenching/digging comparatively.

I'm going to repeat myself one last time. From every single bit of research I have pulled up from dozens upon dozens of different sources every single one of them has all agreed that open loop is cheaper than closed loop every single time. At no point in the last several months of researching this have I ever heard a single time that any possible way is closed loop cheaper than open loop. My particular situation my pond is right next to my house, and I have 5 acres of land. I could easily put in a standard horizontal loop in the ground, I could put in a pond loop, or I could do open loop. I am going with open loop because according to everything I have ever seen it is always cheaper to operate than the other methods. If some how closed loop is cheaper then I want to see some evidence of this, but so far nobody has shown me anything accept the link cdru See Profile posted that said closed loop is better, but that doesn't mean much as they make more money off a closed loop install and they didn't factor in the cost of the pumps on the closed loop making it an unfair comparison anyway. When it comes to unbiased sources not out to make money I can't find one that doesn't say open source is cheaper. If you want to prove me wrong feel free to do so with some link to something unbiased showing closed loop is cheaper to operate.

leibold
MVM
join:2002-07-09
Sunnyvale, CA
Netgear CG3000DCR
ZyXEL P-663HN-51

leibold

MVM

said by New York City Geothermal Heat Pump Manual :

As closed loop piping and the required grouting material add
another layer of heat transfer resistance, the closed loop system is
designed for lower winter entering water temperatures and higher
summer entering temperature. These wider temperature ranges
reduce the effective capacity and efficiency of the heat pump
system. Closed loop piping costs are typically in the same range
as the cost of the heat pumps and thus add to the overall cost of
the installation. Generally, these closed loop systems are more
first cost than the above systems. A compensating increase in the
overall system efficiency can be anticipated by the reduction in
loop pumping costs
. However, the requirement for slightly larger
equipment remains a disadvantage.

You won't find anything that will say that closed-loop is unconditionally better then open-loop because in most situations where both open-loop and closed-loop are feasible the open-loop system tends to have a lower initial cost. The cost difference may not be large (or even in favor of the closed-loop system) when new wells need to be drilled but the difference is significant when an existing well can be utilized for the open-loop.
It is easy to determine operational costs for the small circulation pump in a closed-loop system (the effort to circulate the water in a closed loop is the same no matter how deep the loops are buried). The same does not apply for open-loop systems where it makes a big differences on the lifting power of the well pump depending on the depth of the water table.
This means a true comparison of the operational costs of open-loop and closed-loop systems requires a site-specific analysis.

Even with operational costs likely to be lower in a closed-loop system the question remains whether the difference is large enough to make up for the higher up front installation costs ?
iknow
Premium Member
join:2012-03-25

iknow to Aranarth

Premium Member

to Aranarth
said by Aranarth:

said by cdru:

said by Jack_in_VA:

The EPA has been considering outlawing “pump and dump” open loop geothermal heat pumps, but using open loops that return the water back into the earth via an injection well will most likely continue to be acceptable practice.

I'd have to ask around, but I believe even injection wells are frowned upon.

There was an article in the farm bureau newspaper talking about that. The issue is that when you inject directly into the water table if it is not filtered by the land you can contaminate the ground water directly. This is also a big issues with irrigation wells that are not properly capped. Improperly capped wells was the main focus of the article.

a geothermal system won't contaminate the water. you are pumping back the same water you took out of it, only a little warmer.
iknow

iknow to tomupnorth

Premium Member

to tomupnorth
said by tomupnorth:

said by cdru:

And now the discussion has gone full circle.

Not to mention of course, completely off-topic!

how's that? a geothermal system cools better than an air source AC, so the subject turned to that, and then details about the various geothermal systems had to be discussed to be complete!. there's no sense in using something that may not be beneficial for various reasons.

BillRoland
Premium Member
join:2001-01-21
Ocala, FL

2 recommendations

BillRoland

Premium Member

said by iknow:

said by tomupnorth:

said by cdru:

And now the discussion has gone full circle.

Not to mention of course, completely off-topic!

how's that? a geothermal system cools better than an air source AC, so the subject turned to that, and then details about the various geothermal systems had to be discussed to be complete!. there's no sense in using something that may not be beneficial for various reasons.

Pretty much because he asked if heat pumps cool as good as non-heat pumps. The answer is a simple "yes." The ensuing geothermal discussion regarding open vs closed loops has been interesting, but it doesn't have any bearing on what he asked.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

Jack_in_VA to iknow

Premium Member

to iknow
said by iknow:

a geothermal system won't contaminate the water. you are pumping back the same water you took out of it, only a little warmer.

The EPA and some localities must think it's a potential problem. What I and others think is not going to change anything. Here you can't install an open source heat pump. They must be closed systems.
Jack_in_VA

Jack_in_VA to BillRoland

Premium Member

to BillRoland
said by BillRoland:

Pretty much because he asked if heat pumps cool as good as non-heat pumps. The answer is a simple "yes." The ensuing geothermal discussion regarding open vs closed loops has been interesting, but it doesn't have any bearing on what he asked.

How's that? A air-source heat pump will cool no better or worse than a non-heat pump.
tomupnorth
join:2005-01-14
UpperMidwest

1 recommendation

tomupnorth to BillRoland

Member

to BillRoland
said by BillRoland:

Pretty much because he asked if heat pumps cool as good as non-heat pumps. The answer is a simple "yes." The ensuing geothermal discussion regarding open vs closed loops has been interesting, but it doesn't have any bearing on what he asked.

Thank you. One guy that gets it!

boogi man
join:2001-11-13
Jacksonville, FL

boogi man to Ken

Member

to Ken
so Ken what you're saying is that you don't actually know. go get real estimates and get back to us. there is a reason i asked you for the particulars of your installation.
boogi man

boogi man to iknow

Member

to iknow
when if there is contamination from the a/c it's going straight into the aquifer, clearly bad for anyone that wants to drink that water in the future.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

1 recommendation

Jack_in_VA to tomupnorth

Premium Member

to tomupnorth
said by tomupnorth:

said by BillRoland:

Pretty much because he asked if heat pumps cool as good as non-heat pumps. The answer is a simple "yes." The ensuing geothermal discussion regarding open vs closed loops has been interesting, but it doesn't have any bearing on what he asked.

Thank you. One guy that gets it!

Except his answer to the question was incorrect. A heat pump in cooling mode is no better or worse than a non-heat pump. The units are basically the same except for the reversing valve and some controls.
tomupnorth
join:2005-01-14
UpperMidwest

1 recommendation

tomupnorth

Member

said by Jack_in_VA:

Except his answer to the question was incorrect. A heat pump in cooling mode is no better or worse than a non-heat pump. The units are basically the same except for the reversing valve and some controls.

But how do you get "incorrect" out of what he said?
quote:
[laserfan] asked if heat pumps cool as good as non-heat pumps. The answer is a simple "yes."
Are you from an alternate universe where "yes" means "no"? Or vice-versa?

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

1 edit

Jack_in_VA

Premium Member

NM

leibold
MVM
join:2002-07-09
Sunnyvale, CA
Netgear CG3000DCR
ZyXEL P-663HN-51

leibold to iknow

MVM

to iknow
said by iknow:

a geothermal system won't contaminate the water. you are pumping back the same water you took out of it, only a little warmer.

Even when it is perfectly functioning the returned water will contain either trace amounts of chemicals (leached from plastic piping) and/or metals. Depending on the pump design it may contain small amounts of lubricating oils. Also of concern is exposing the open-loop water to air (oxygenating the water) which would allow harmful bacteria to grow in the aquifer.

However the main concern with injection wells is the potential to quickly and permanently ruin an aquifer when something goes wrong. Given enough time, something always will.
Aranarth
join:2011-11-04
Stanwood, MI

Aranarth to iknow

Member

to iknow
We are talking about direct injection.
That is the system is an open loop but the end of the loop is back in the ground at the same depth it was taken from. This can be bad if the water is contaminated on the through the loop.

garys_2k
Premium Member
join:2004-05-07
Farmington, MI

garys_2k to leibold

Premium Member

to leibold
I was the guy who brought up the injection of water taken from an aquifer back into the same aquifer, albeit a bit warmer. Those are good enough reasons to not allow that.

linicx
Caveat Emptor
Premium Member
join:2002-12-03
United State

1 recommendation

linicx to tomupnorth

Premium Member

to tomupnorth
The bottom line is both work well in moderate temperatures. The heat pump will not work well when the temperature is -80F.

I was in a house with a heat pump one sunny winter day when it was near 10F. It was not a warm or fuzzy experience.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

1 edit

Jack_in_VA

Premium Member

said by linicx:

The bottom line is both work well in moderate temperatures. The heat pump will not work well when the temperature is -80F.

I was in a house with a heat pump one sunny winter day when it was near 10F. It was not a warm or fuzzy experience.

Really? I'm in my home when the temperature never gets that low and I'm warm and fuzzy.

United States....Virginia......Mathews County

**Super Premium**

linicx
Caveat Emptor
Premium Member
join:2002-12-03
United State

linicx

Premium Member

Really. I'm in my home when the wind chill is a minus 80F and I'm warm and fuzzy. I don't have a heat pump.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

1 edit

Jack_in_VA

Premium Member

I'm in my area where the temperature never gets that low, I'm kept warm and fuzzy in my home by my heat pump. Wind chill has no effect on anything mechanical.

United States....Virginia......Mathews County

**Super Premium**
tomupnorth
join:2005-01-14
UpperMidwest

1 recommendation

tomupnorth to linicx

Member

to linicx
said by linicx:

The heat pump will not work well when the temperature is -80F.

Hmmm -80F huh. So you must have been in Alaska last January when the all-time record was in jeopardy!



Heat pumps work poorly enough below freezing that I never run mine, at least not deliberately, below 35F. Heat strip time.

All forum members from Alaska with heat pumps please come forward.


solar
@dsl.net.au

solar to tomupnorth

Anon

to tomupnorth
Actually performs higher in heating mode but no less in cooling compared to cool only sister model

Toaster
@dsl.net.au

Toaster to tomupnorth

Anon

to tomupnorth
Go Reverse be comfortable year round save energy save money
no negative simply takes heat outside or puts heat inside