Issue:
Is a flow switch required?
Resolution:
RTAA, RTWA, RTUA Chillers: Per page 28 of the RTAA IOM (RTAA-SVX01A-EN), a flow switch is not needed for proof of flow.
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Chilled Water Flow Switch
- Chilled Water flow protection is provided by the UCM without the need for chilled water flow switch. A flow switch for chilled water is strictly discretionary but if not installed, a signal must be sent to the chiller control panel to indicate that water flow has been established, eg. chilled water pump motor starter auxiliary contacts, building automation system, etc.
- If additional chilled water flow protection is desired, use a field-installed flow switch or differential pressure switch with the pump motor starter auxiliary contacts to sense system water flow. Install and wire the flow switch in series with the chilled water pump motor starter auxiliaries (refer to "Interlock Wiring").
Notes:
Changes:
Other Question/Problem/Cause Statements:
- Is a flow switch required?
- Do we need a flow switch with a remote evaporator?
- Flow Switch?
- Flow Proving?
- Proof of Flow?
Facts:
- RTAA 70-125 TON (PUEBLO)
- Air-Cooled Chiller (Pueblo) (RTAA 70-125 Ton)
- Compressor Chiller (Pueblo) (RTUA)
- Water-Cooled Chiller (Pueblo) (RTWA)
Document Identifier: DOC-92246
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.