5 Ton GSHP Build - Page 5

randen · 04-09-14, 11:28 AM

Mike

45 % silver solder. Already switched. Dam work breaking my concentration!!!!

Randen

randen · 04-13-14, 08:34 PM

The refrigeration circuits have been corrected. Everything is silver-soldered and brazed. The vacuum pump is employed and the system is holding the vacuum.

This new version of heat-pump may strongly resemble a previously constructed machine. I can only hope I didn't infringe on any licenced methods. The resemblance wasn't entirely deliberate.

Next will be the water circuits. Hopefully my luck will hold and it will be leak free.

Randen

NiHaoMike · 04-13-14, 09:56 PM

It it hard to tell from 2D photographs, but if there are points where the copper tubing touches or gets close to another pipe or other hard objects, put a little foam rubber or something (maybe even a few layers of duct tape) in between to prevent them from rubbing through.

Also, pull vacuum from both sides. That's the proper way to do it. Then put in a holding charge (a few PSI of nitrogen, up to 150 PSI or so if you're doing a pressure test) until you're ready to finish the triple vacuum and tune it. You can also finish the triple vacuum outright and then put in 50 PSI of refrigerant for a holding charge, then add more when you're ready to tune it.

AC_Hacker · 04-14-14, 01:25 AM

Quote:

Originally Posted by randen

...Everything is silver-soldered and brazed. The vacuum pump is employed and the system is holding the vacuum...

Really a great looking job.

-AC

randen · 04-14-14, 07:48 AM

Nihaomike

Don't worry spent some time bending tube. There are no areas were the tube comes close to touching. It won't be difficult to wrap the tubes with rubber insulation tubes.

I want to get it in soon so I can get a feel for its performance while some nights still get cool.
Looking real forward to kick butt air-conditioning in the shop this summer.

Randen

AC_Hacker · 04-14-14, 09:55 AM

Quote:

Originally Posted by randen

I want to get it in soon so I can get a feel for its performance while some nights still get cool. Looking real forward to kick butt air-conditioning in the shop this summer.

Randen,

I have forgotten what your air conditioning output is like.

Last I remember, you were running chilled water through a converted gas-heater core.

If I recall correctly, you were successful in getting a cooling effect, but there was a problem with increased relative humidity.

Maybe Mike can use his advanced refrigeration knowledge along with this Mollier chart for R290 to design a de-subcooler for your system, so as to reduce the humidity therein.

-AC

randen · 04-14-14, 10:27 AM

AC-Hacker

The cooling load would be about 3 ton the old 2 ton air to air couldn't keep up with the machines running.

The air handler I had rescued from the scrap dealer was a refrigerant slant coil with an additional hot water exchanger. I had converted the slant coil to water by removing the cap-tube and installing a water manifold. So there is actually 2 heat exchangers (water to air)in the handler.

Before the hacked heat-pump was made the ground loop was installed. I had tried an experiment, to pump the ground loop water (12 Deg.C) through the air handler, to air condition the shop. Although condensation poured from the coils and the temp did drop it wasn't enough. The result was shop air temp of 26 deg. C and almost 100% rel. humidity.

I understand now one would require coil temps much lower to wring out as much moisture as possible.

5 tons of cooling should do-it. With the glycol I should be able to get near zero coolant through the coils. I'll keep the renovators posted.

Mike and I are in-contact for this and other projects of interest.

Randen

jeff5may · 04-14-14, 07:07 PM

Here's an idea: you could pre-cool the air as before, using the 12 degC loop water before it went into your condenser hx. This would extract lots of moisture at uber-high COP. Directly downwind, the colder evap loop water hx would drop the air temp even better due to the reduced latent load. A double whammy.

You have built a 20,000 dollar industrial chiller. Now all it needs is a stainless steel rack mount enclosure around it and some big, ugly gauges. The bigger and uglier, the higher you could make the thing worth. Super sanitary.

stevehull · 04-14-14, 07:59 PM

Jeff,

I have been thinking of doing this with my open loop GT heat pumps (precooling return air with water) for summer AC

My well water temp is about 60F and I can get a real cheap evaporator (that doesn't leak) to put before existing GT heat pump air coil.

When the unit is on, it uses ~ 5 gallons per minute (~ 40 L/min). Easy to plumb the water exiting this precooler to then go to the GT heat pump input. I bet the water temp is now a few degrees higher, which means a lowering of the EER.

Clearly, I am not going to get any latent water removal, but it should pre-cool the return air. Return air is about 80 F or so.

Do you think the time/trouble is worth it? Or am I trading just one efficiency for another . . . .?

Thanks . . .

Steve

randen · 04-14-14, 09:32 PM

Jeff, Steve

I have heard of an installation were the contractor made up a pre-cooler using ground loop cooling. The installation was an expansive Geo-thermal in-door pool heating and air conditioning/heating system. During the summer months with all the glass some air-conditioning of the envelope .was needed. The installer installed a air handler that first ran the cool ground loop water through to help drop out the moisture. Then condition after that.

I don't have any information as per the economy of the system. But it had been done and wrung out a lot of condensate.

Randen

04-13-14, 08:34 PM	#42
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	5 Ton GSHP Build The refrigeration circuits have been corrected. Everything is silver-soldered and brazed. The vacuum pump is employed and the system is holding the vacuum. This new version of heat-pump may strongly resemble a previously constructed machine. I can only hope I didn't infringe on any licenced methods. The resemblance wasn't entirely deliberate. Next will be the water circuits. Hopefully my luck will hold and it will be leak free. Randen Attached Thumbnails

04-13-14, 09:56 PM	#43
NiHaoMike Supreme EcoRenovator Join Date: Oct 2008 Location: Austin, TX Posts: 1,154 Thanks: 14 Thanked 257 Times in 241 Posts	It it hard to tell from 2D photographs, but if there are points where the copper tubing touches or gets close to another pipe or other hard objects, put a little foam rubber or something (maybe even a few layers of duct tape) in between to prevent them from rubbing through. Also, pull vacuum from both sides. That's the proper way to do it. Then put in a holding charge (a few PSI of nitrogen, up to 150 PSI or so if you're doing a pressure test) until you're ready to finish the triple vacuum and tune it. You can also finish the triple vacuum outright and then put in 50 PSI of refrigerant for a holding charge, then add more when you're ready to tune it. __________________ 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... Last edited by NiHaoMike; 04-13-14 at 10:00 PM..

04-14-14, 10:27 AM	#47
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	AC-Hacker The cooling load would be about 3 ton the old 2 ton air to air couldn't keep up with the machines running. The air handler I had rescued from the scrap dealer was a refrigerant slant coil with an additional hot water exchanger. I had converted the slant coil to water by removing the cap-tube and installing a water manifold. So there is actually 2 heat exchangers (water to air)in the handler. Before the hacked heat-pump was made the ground loop was installed. I had tried an experiment, to pump the ground loop water (12 Deg.C) through the air handler, to air condition the shop. Although condensation poured from the coils and the temp did drop it wasn't enough. The result was shop air temp of 26 deg. C and almost 100% rel. humidity. I understand now one would require coil temps much lower to wring out as much moisture as possible. 5 tons of cooling should do-it. With the glycol I should be able to get near zero coolant through the coils. I'll keep the renovators posted. Mike and I are in-contact for this and other projects of interest. Randen Attached Thumbnails Last edited by randen; 04-14-14 at 10:30 AM..

04-14-14, 07:07 PM	#48
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,431 Thanks: 431 Thanked 619 Times in 517 Posts	Here's an idea: you could pre-cool the air as before, using the 12 degC loop water before it went into your condenser hx. This would extract lots of moisture at uber-high COP. Directly downwind, the colder evap loop water hx would drop the air temp even better due to the reduced latent load. A double whammy. You have built a 20,000 dollar industrial chiller. Now all it needs is a stainless steel rack mount enclosure around it and some big, ugly gauges. The bigger and uglier, the higher you could make the thing worth. Super sanitary. Last edited by jeff5may; 04-14-14 at 07:10 PM..

04-14-14, 07:59 PM	#49
stevehull Steve Hull Join Date: Dec 2012 Location: hilly, tree covered Arcadia, OK USA Posts: 826 Thanks: 241 Thanked 165 Times in 123 Posts	Jeff, I have been thinking of doing this with my open loop GT heat pumps (precooling return air with water) for summer AC My well water temp is about 60F and I can get a real cheap evaporator (that doesn't leak) to put before existing GT heat pump air coil. When the unit is on, it uses ~ 5 gallons per minute (~ 40 L/min). Easy to plumb the water exiting this precooler to then go to the GT heat pump input. I bet the water temp is now a few degrees higher, which means a lowering of the EER. Clearly, I am not going to get any latent water removal, but it should pre-cool the return air. Return air is about 80 F or so. Do you think the time/trouble is worth it? Or am I trading just one efficiency for another . . . .? Thanks . . . Steve __________________ consulting on geothermal heating/cooling & rational energy use since 1990

04-09-14, 11:28 AM	#41
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	Mike 45 % silver solder. Already switched. Dam work breaking my concentration!!!! Randen

04-14-14, 07:48 AM	#45
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	Nihaomike Don't worry spent some time bending tube. There are no areas were the tube comes close to touching. It won't be difficult to wrap the tubes with rubber insulation tubes. I want to get it in soon so I can get a feel for its performance while some nights still get cool. Looking real forward to kick butt air-conditioning in the shop this summer. Randen

04-14-14, 09:32 PM	#50
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	Jeff, Steve I have heard of an installation were the contractor made up a pre-cooler using ground loop cooling. The installation was an expansive Geo-thermal in-door pool heating and air conditioning/heating system. During the summer months with all the glass some air-conditioning of the envelope .was needed. The installer installed a air handler that first ran the cool ground loop water through to help drop out the moisture. Then condition after that. I don't have any information as per the economy of the system. But it had been done and wrung out a lot of condensate. Randen