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operation temps and flow rates

Last Post 14 Jul 2011 04:22 PM by jonr. 8 Replies.

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gregs

New Member

Posts:29

08 Jul 2011 02:32 PM
I am looking for any information regarding water temperatures and efficiency. I have a Trane WSHP that's about 10 years old connected to an open loop well water system set at 40/60psi. I have a manual throttling valve that I can adjust the water flow with. It has always been set at about 1/2 flow but I haven't checked the actual GPM, the only way I could do this would be with a 5 gallon bucket and a stop watch. I have checked the water temperature and air temperature and have the following data. When my water filter is clean the incoming water is 75 degrees and the outgoing water is 87 degrees and as the filter gets plugged up over time and more restricted the outgoing water temperature can rise to 98 degrees. I usually clean the filter before that happens as my water pressure in the house drops to low. My outgoing air temperature at the closest register is between 52 and 54 degrees with an inlet temperature of 80 degrees in the summer with the outgoing water temperature between 87 and 98 degrees. I haven't had any problems with the operation but wondered if I should increase or decrease the water flow for better efficiency. <!-- / message -->

jonr

Senior Member

Posts:5341

08 Jul 2011 04:52 PM
Unless the instructions say otherwise, I'd use the bucket method to adjust flow to 1.5 gallons per ton. Throttling is somewhat wasteful, better would be to have your well produce some low pressure that just achieves the 1.5 gpm/ton and then use a booster pump for household water.

engineer

Veteran Member

Posts:2749

11 Jul 2011 11:59 AM
Where are you that well water comes in at 75*F...south TX or Florida? I agree in principle with jonr's comment...trouble is, implementation may be more costly / complicated than results will justify

Curt Kinder <br><br> The truth is incontrovertible. Malice may attack it, ignorance may deride it, but in the end, there it is - Winston Churchill <br><br><a href="http://www.greenersolutionsair.com">www.greenersolutionsair.com</a>

gregs

New Member

Posts:29

11 Jul 2011 01:34 PM
I am located in North Florida. The house was built about 30 years ago with a WSHP and the plumbing for it is integrated with the rest of the house so seperating it out would be a lot of work. I am trying to determine if its more efficent to operate it at a higher output temp and possbily use less water. And if there is some differential temps you adjust for.

engineer

Veteran Member

Posts:2749

11 Jul 2011 04:16 PM
Bucket method is OK for open loop...low tech but accurate. It is hard to know the best the best operating point - tradeoff between compressor power and pump power. My gut suggests leaving water should be not much warmer than 90 to keep efficiency up. Do you really need 40/60 for domestic use? I use 30 / 45 and have good strong shower water pressure 20+ feet above the well PM or email me if you are reasonably close to Jax and might like me to take a look Curt "at" greenersolutionsair "dot" com

Curt Kinder <br><br> The truth is incontrovertible. Malice may attack it, ignorance may deride it, but in the end, there it is - Winston Churchill <br><br><a href="http://www.greenersolutionsair.com">www.greenersolutionsair.com</a>

gregs

New Member

Posts:29

14 Jul 2011 08:48 AM
I know they use similiar units in commercial application with closed loops and cooling towers. Does anyone know what typical water temps are for those applications?

jonr

Senior Member

Posts:5341

14 Jul 2011 09:12 AM
The only way to really answer you question is to measure COP - including the power used by the well pump.

gregs

New Member

Posts:29

14 Jul 2011 11:05 AM
Power consumption is definately important but I am also looking at how best to operate it. I wouldnt want to run 20gpm thru it and the water only change a few degrees but I also dont want to run it to lean and over stress the compressor and shorten its life. I was hoping to find some general guidelines for operating a WSHP with different type of loops.