Installation, Start-Up, Adjustment and Maintenance Manual
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5.3 CONTROL SWITCH WIRING AND THERMOSTAT LOCATION
CONSENT SWITCH WIRING
If DDC is not used, a consent switch that provides an ON/OFF function is to be connected to the R and Y on
the S61 board. This wiring will carry 24-volt current and it is recommended to use a cable with the correct
number of color-coded 18 AWG wires.
An isolation relay MUST be used to separate the chiller’s transformer from any additional
equipment having a transformer or damage to the S61 board will occur. Isolation relays must have
a 24-volt AC coil, which does not present more than 0.25 amp load to the control circuit.
THERMOSTAT LOCATION
If the control switch is a thermostat, the thermostat should be located on an inside wall about 54 inches
above the floor. It should be located so that it will no be affected by any of the following items:
- Discharge air from a supply grille
- Drafts
- Direct sunlight through a window or glass door
- Electrical Appliances such as television, radio or lamps.
The thermostat should be located so that it senses the average temperature of the conditioned space. The
thermostat should be mounted according to the manufacturer’s instructions (packaged with the thermostat).
THERMOSTATS USING A MERCURY BULB SWITCH MUST BE LEVEL.
If the thermostat has a built-in
heating anticipator, this must be set as required by the heating unit load.