24000 BTU AC Unit conversion to geothermal well water source

[b420ady]

Yes, it makes a lot of sense, I m very aware of this. but I still have to do this project also....I need the heat
About the exterior thermal insulation there are chances it might not happen in time case in which the house will pass the winter without the insulation but I ll still have to warm up somehow to survive the frost.

[b420ady]

Originally Posted by jeff5may

Downstream in the aquifer may or may not be downhill on the ground. Check with a geologist or water utility in your area, they will definitely know what exists underground. It may or may not be against the law to dump water back into the natural source: again, the pro's in your area will know the details. Also remember that cold water is heavier than warm water, so if you pump cold water back in, try to inject it deeper than your source well.

The effect of recirculating cold water through your well may not show up immediately. Usually it takes a few seasons of use to happen. What happens is after a few years of use, your source water temperature may change (for the worse) a few degrees. This trend will slowly continue with use until the ground can make up the difference. If you are heating and cooling throughout the year, these modes cancel each other out to the extent of duty cycle. For example: if you extract 2000 tons of heat in the heating season, but only add back 1500 tons during cooling season, the net loss of 500 tons will have an easy time being made up by the Earth. If you only heat with the system, there will be 4 times more heat to extract from underground.

Making your own evaporator is not all that difficult physically. The main difficulty in building is making everything not leak. The more difficult aspect lies in the design of the heat exchanger. Making absolutely sure the materials and configuration will handle your loading requirements (in a worst-case situation) on paper before you build anything is super important! Some fail-safe elements must be included in the control system as well. In your application, when something goes wrong, the heat exchanger will try to freeze the water flowing inside. This event is usually catastrophic, so failure mode analysis and control is absolutely necessary. Making sure your design can handle whatever the world throws at it before it is built can mean the difference between a unit that tries to flood your basement (while you aren't there to stop it) and one that does what it should for years.

Its actually great what you are telling me because our cold season is shorter the the hot season and I might put back in the summer more than I use in the winter.
What I m wondering is what flow rate of water I need to feed this unit ? So I can make an idea on pumping water power costs.
About the specialists in my area and laws for putting back the water in the ground .... we have none of those above
The house is in a very small village on a hill,about 30 houses.... my water well is the only piece of intelligence about this area as its the deepest well bored around here...

[stevehull]

in a GT heat pump, each 12,000 BTU delivered requires a water flow of 2-4 gallons per minute (8-17 liters/min). This can be a LOT of water!

Water pump costs depend on how far up the well you have to pump and how much resistance is in the pipe system.

Steve

[b420ady]

That waterfow is about as big as my actual water pump and indeed its a huge quantity of water...it will mean I ll pump daily about 40 cubic meter of water, so the power consumption for pumping water will be considerable as I pump from over 30 meters depth. I ll have to see how much this will afect the final COP of the unit.

[b420ady]

I ve managed to bring home half of the unit today ..... I mean the indoor unit + 2 remotes
I could not get the outdoor unit because it could simply not fit through my car back door or trunk
anyway I paid half of the price with the agreement that he will deliver the outdoor unit with his car in the weekend and I ll pay the trip costs to here also.

After reading the label from indoor unit I ve found out that the heating power in the actual setup is 7.8 KW which is 26614 BTU , so the COP of this unit now is 3.12
I ve seen that all the pipes and wires were just cut short .... is that normal to cut them so short ??? I mean I will pay a technician to weld the pipes and fill it with refrigerant and pay it as a normal AC Unit install service which should be less than 100 USD + the pipes cost and trip to country side paid for the technician... but I don t know exactly if he can weld them because they are so short .... how do I deal with this ?

The outdoor unit looks better than the indoor one .... I mean the indoor unit its full of paint and dirt and maybe a mice nest inside as it was stored in the yard... i just made this photos for today and I ll investigate and clean it more in the next days....I think I will need some acetone to remove the paint or what ? Can you point some substances to make it look nice again and more white as its pretty yellow now .... Or I can paint it with something at the end ???


I have some new questions:

-how far away I can put the outdoor unit from the indoor unit ? because the well is inside a small 1x2m basement construct 1,5 meters away from the house and I m thinking to host the outdoor unit there, but in order to put the indoor unit to blow from the living room pointing to the bedrooms doors I will have to go a much longer path around the house

- can I add somehow to the system another heat exchanger or desuperheater or what is its name to preheat also water for a electric boiler for the bathroom and kitchen ?

[b420ady]

PS: Another issue is that here sometimes when it rains or snows hard or its storm the electric power can be off like 50 times in a day .... and lets say in worst conditions a whole day without electricity once or twice in a year.... case in which I ll have to setup a procedure to not get my coil frozen as you said.

[b420ady]

PS 2: while searching for this unit model I ve got to another unit named the same :

KFR Split Air Conditioner 24000 BTU 208~230V/60HzAir Conditioners, Range Hoods-Factory Direct Outlet

Apart from being a total different unit from what I ve brought I ve seen a curios thing .... the power imput is 1.25KW and it makes 24000 BTU heat so 7 KW which means a COP of 5.6 .... is that real or its fake marketing ?

[b420ady]

I keep trying to find the service manual for this unit and until now the best close i think it is this one

24000btu Heat Pump

But I m not sure at all because KFR-70GW/W seems to be a model name for a lot of brands ,,,,, can someone help out ?

[b420ady]

Apparently this thread went in to a black hole.... I ve checked it like 30 times a day anxious for a reply
I still have to wait 2 days for the outside unit and in the mean time I ve did a lot of research about water to freon heat exchangers, in the mean time I also learned that you don t weld pipes at a heat pump but you braze them
Also I was thinking to go at some junkyards and search for some heat exchangers, can you tell me in what devices I can find some plate heat exchangers ? because for sure I won t find a water to water heat pump at the junkyard.
I also know that you can find plate heat exchanger at cars , their purpose is to do heat exchange from water to oil .... can they be used for water to freon ?? They are small in size but I guess there should be bigger ones for trucks or heavy machinery or there is any chance I can build my own from stainless steel sheet cut at a waterjet CNC ?

PS: I ve made a DropBox folder were I will share books and manuals I ve found on my research because for sure it might help someone someday ..... I wish I had time to read them all

SHARED FOLDER: https://www.dropbox.com/sh/3owy0iq7o...jQSVmrC-a?dl=0

[jeff5may]

Haven't been really active on the forums lately. I am on an 8 day a week schedule at the job, working 60+ hours a week, and besides a holiday shutdown before the new year, it looks like this will continue all the way through June or July. Meanwhile, 2 of my vehicles decided to break down on me. The gas-saver Saturn is troubleshot: previous mechanic's inadequate repair led to repeat failure. It awaits donor car seller to match my schedule, then it's getting an engine transplant. The Silverado/Sierra is similar: previous hot-rodder recycled too many old parts and/or didn't clean enough while it was apart, leading to coolant leakage out the tailpipe and other rubber things. Preliminary tests point to head gasket or cracked head.Maybe during the shutdown I will have time to fix them both, plus have time to have a life, maybe not. But I digress...

The literature you have linked to doesn't completely agree with what your unit nameplate says. Most or all of it says the units run with R-410a. The unit you have looks a little older. The general ideas and methods will be the same, but specific specs will differ. The documents describe a 13 SEER line of units that are not really built to heat well below about -10 degC outdoor temperature. Some of the units automatically quit when outdoor temp falls below -15.

When you get your outdoor unit, look at the compressor nameplate. The model number will tell us all kinds of stuff about what you really have. Since you need heat quickly, just rig it up in its stock configuration to make sure it works. You should be able to save lots of money this heating season with it. Going straight air-source with the outdoor unit, you will need a backup heat source when the temp drops below this threshold. Above maybe -10 degC, it should serve you well before you modify it. Plus, you will get hands-on knowledge of how well the existing controls are.

A plate heat exchanger may or may not work well with your water source. If your well water has anything strange in it, the plates will get coated and fouled with whatever is in the water. Not bad for an experiment, but to run the plate exchanger a lot requires flushing and cleaning on a schedule.