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Help me diagnose the problem pls.

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FREEZYBREEZE

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Discussion starter · #1 ·
Went on a "Little Cooling" call this morning. Overcharged was the initial diagnosis so i removed 8oz. of R22. This unit has always acted a little funny and I think there are more problems than 1. Would like to hear feed back. Got a call back today saying still little cooling. Customer wants House 74 and will only come down to 77 its 95 here in GA today. Has worked fine early this summer with temps in 100 degree range.

Water was 110 in and 118 out
forgot to get indoor air out temp.

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Discussion starter · #3 ·
I was thinking the same thing. The only geothermal I've ever installed was a 2 ton and water temp would run about 85 degrees in.

This customer has a sister who lives next door with a similar system and her loop runs warm like that too. Too much freon in hers ( a few ounces!) and the compressor will over heat and take a 2 hr break, so its a balancing act between cooling the house and overheating the loop/compressor. Both loops are slinky style installed about 4 feet down and in sandy type soil. Both customers run sprinklers over the loops when the soil is dry to help the systems perform better. With no other systems to compare them to, it has me stumped. Its easy to say it needs more loop but a little harder to do the repair. Especially when these units have been working (allbeit not so well) for 8 years.
 
#4 ·
FREEZYBREEZE said:
Went on a "Little Cooling" call this morning. Overcharged was the initial diagnosis so i removed 8oz. of R22. This unit has always acted a little funny and I think there are more problems than 1. Would like to hear feed back. Got a call back today saying still little cooling. Customer wants House 74 and will only come down to 77 its 95 here in GA today. Has worked fine early this summer with temps in 100 degree range.

Water was 110 in and 118 out
forgot to get indoor air out temp.



Image
Click to expand...

That is some hot water, Have you amped the water pump, any way to verify proper water flow?

BTW whose app is that?
 
Discussion starter · #8 ·
The system has a double pump set up and an amp check says they are working the way they should. I would guess the loop setup is incorrect also. What would those of you who work on alot of these expect a proper loop temp to be. The system is a 4 ton BTW.

The system has probably never worked exactly the way it should. The home owner even has faucets (placed there by the original system installer in hopes to make it cool) 1 faucet lets cold water in (pump and dump style) from the homeowners well. The homeowner knows way to many tricks to keep this thing cooling.

The app is HVACbuddy for iPhone and android. Its awesome. All of my techs and installers have it for their phone. Very good way to check and verify the charge in any type of system.
 
Discussion starter · #10 ·
The loop i installed on the 2 ton was 6 feet down 2 feet wide run out, fill with 2 ft of dirt and returned to header pit and then covered up. After about 3 feet down the soil will start to be a mix of sand and clay. Mostly sand.
 
Discussion starter · #11 ·
Danielandersen2 said:
I like the "beer can" reference for superheat


I didn't get that at first but then I looked at the icons on the app, saw the beer mug, and it clicked. I use the app everyday so it took me a minute. The app is very cool. Especially for new techs. We always refer to the manufacturers recommended subcooling, but when its not available the app gets the charge spot on.
Click to expand...
 
#12 ·
loop is too hot. You should probably do pressure in and pressure out to make sure the pumps are actually pumping, if there is a broken shaft the pump will still show amperage but not be pumping. Around here (Ohio) I design the loop never to be warmer than 85 degrees, when we start digging and find sandy soil we have to recalculate the loop, We bury them 5-6 feet here and I am not a fan of the slinky loop. Lots of people put them in and have no problems, I just have not bought in to them
 
Discussion starter · #13 ·
Thats another thing. This loop isn't sealed or pressurized. It has a reservoir. usually the top is off of it and sometimes the homeowner puts ice in to cool the loop. He says its never been pressurized.
 
#15 ·
Sounds like a very poor loop design. Here we drill 1 200' hole per ton
 
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#16 ·
I would bet this calculator is a bit off since water loops should be much cooler

I would say low on charger and lsat is high due to lack of heat xfer

Your SH should be lower and you VSAT should at least mid 40s with a IWB of 66.

What was your SH before you let some r22 out.
 
Discussion starter · #17 ·
The unit has a TXV. It has been replaced about 3 yrs ago.

The homeowner has the ability to run fresh water thru the loop to cool it down (Pump and dump style). Rechecked the unit (in a hurry so i didn't take notes) but i had to add back 20oz of r22 and got pressures and temps that resemble air to air systems i'm familiar with. Water in (80 deg) Water out (100 deg.) suction pressure (75) suction line temp (46 deg.) hi side pressure (199) line temp (i cant remember) 16 deg subcooling according to the gauges). The loop is 4000 ft long installed slinky style in 4 trenches 4 ft deep 1000 ft long each. This is a 4 ton system. What can be done at this point to make the loop more effective?
 
#18 ·
FREEZYBREEZE said:
The unit has a TXV. It has been replaced about 3 yrs ago.

The homeowner has the ability to run fresh water thru the loop to cool it down (Pump and dump style). Rechecked the unit (in a hurry so i didn't take notes) but i had to add back 20oz of r22 and got pressures and temps that resemble air to air systems i'm familiar with. Water in (80 deg) Water out (100 deg.) suction pressure (75) suction line temp (46 deg.) hi side pressure (199) line temp (i cant remember) 16 deg subcooling according to the gauges). The loop is 4000 ft long installed slinky style in 4 trenches 4 ft deep 1000 ft long each. This is a 4 ton system. What can be done at this point to make the loop more effective?
Click to expand...
That is a very high temperature increase on your loop. Looks like low flowrate.
 
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