Connecting Loops & Heat exchangers for VRF hybrid system

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Connecting Loops & Heat exchangers for VRF hybrid system

Postby e.duff » Tue May 21, 2019 4:21 am

Hi All,

I'm trying to join two water loops together; the primary loop uses a condenser loop cooling tower with supplementary heat injection in winter. A secondary loop is separated from the primary loop via a water-based heat exchanger. This secondary loop is essentially a large pumped manifold and is used as the heat exchange mechanism for 15 individual on-floor water-cooled VRF condenser units. The on-floor units are VRF Fan Coil Units with tempered fresh air from central AHUs.

The secondary loop runs the length of the building and delivers the heat from the on-floor VRF units to the primary loop cooling towers for rejection, or delivers warm water from the boilers to the VRF units as required.

Problem to solve
1.) I am trying to connect the primary loop components together (i.e. the cooling towers, boilers, and water heat exchanger, but cannot get the boiler to connect to a condenser loop

2.) I can't I get/find a fluid-fluid heat exchanger to separate the primary and secondary loop

3.) I then need to add the VRF condenser units into the secondary loop, and add the secondary loop back into the heat exchanger.

Can anyone help with this? Is this possible in v4.7 of Design Builder?

Many thanks to anyone who takes the time to read through.


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