Parallel Pumping in Condenser Applications: Part 5 of 5

Parallel Pumping in Condenser Applications: Part 5 of 5

Over the last few weeks the we’ve looked at pumping issues with multiple condensers and pumps.  We have received questions about the topic, including these two:

Why do I need cooling tower outlet On-Off valves if I have an equalizing line?

Why do we see outlet On-Off valves on almost all jobs in North Carolina and only half the jobs in Michigan and Northern Ohio?

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Parallel Pumping in Condenser Applications: Part 2 of 5

Parallel Pumping in Condenser Applications: Part 2 of 5

In Part 1 of this series we offered an example of a condenser water pumping system with 800 GPM per condenser for a total of 1600 GPM with the third condenser serving as standby. The tower elevation or lift is 10 feet, the condenser (with the 2-way valve and balance valve) has 20 feet of pressure drop, and the common piping with any safety factor has 30 feet of pressure drop. But there was a problem....

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Parallel Pumping in Condenser Applications: Part 1 of 5

Parallel Pumping in Condenser Applications: Part 1 of 5

Applying a single constant speed pump for each condenser in a chilled water application is a normal design for the HVAC engineer. Some chiller manufacturers suggest piping the pumps with a common header and activating each pump as the condensers are staged on. However, there is a hidden issue with this approach, which, if not addressed may cause major problems....

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