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Pion
08-25-2011, 09:08 PM
Hey guys ---Newby here, but not to the trade. My question concerns the proper way to configure piping and wells, sensors, float switch, etc. on new 25 ton heat exchanger for chiller. In other words, what should be on inlet and in what order, and same for outlet? Thanks for your help.

basprofessional
08-27-2011, 01:18 PM
Can you be a little more specific? What type of chilled water piping configuration are you referring too. What are you attempting to achieve?

Pion
08-27-2011, 03:35 PM
basprofessional........thanks for your reply. Was just wondering if the order of components in the inlet and outlet pipes matter at all, and if flow switch should be in inlet or return, if that even matters. Also, have you used flat plate type exchangers?

basprofessional
08-27-2011, 06:58 PM
As far as flow switches go we always put them on the outlet side of the chiller barrel. The water pressure across the barrel drops and the low pressure side is on the outlet of the barrel. With that said, install the flow sensor on the outlet of the exchanger. If the pump varies in speed set the flow switch to shut off just below lowest water flow allowed. Iím not sure what you mean by flag heat exchanger are you referring to a plate exchanger?

Pion
08-27-2011, 08:02 PM
Thanks, bp.....The flat plate exchanger, (my first experience with one), is from Danfoss. We're replacing an old Carrier chiller with water cooled condenser with Trane air cooled condenser and using this flat plate thing for evap. I know it sure seems small for the tonnage (25). The txv has no distributor- just feeds into the exchanger. Apparently they work, at least until they start leaking.

basprofessional
08-27-2011, 11:44 PM
Let me guess, the new chiller model number is a CGAM? The flat plates have pressure drops just like any other chiller barrel. So install the flow switch down stream of the flat plate. Follow the directions of the manufacturer of the flow switch by making sure the flow switch is in a straight section of pipe. Other than that it does not matter if the temp sensors are down stream of the flow switch or not. Just a word of caution about the CGAM, the chillers have issues and Trane is on top it them. Thereís software up date which deals with keeping the flat plate from freezing up. The other problem has been with the condenser fans going out. If the condenser fan makes a strange grinding noise when they start up there is a problem. The sound is like someone grinding gears in their manual transmissions in their car.