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SpaceKeeper Console (SKC) – Installation Operation Maintenance Manual
© Copyright 2013 CGC Group Inc. Installation Operation Maintenance Manual is Subject to Change without Notice Last Revised Nov 15, 2019
To ensure correct operation, centralized equipment located within the building mechanical
room is automatically controlled to provide each heat pump unit with water that is at the
appropriate temperature and flow rate.
The unit circuit board incorporates six relay outputs with the following functions:
K1 – Auxiliary relay for cooling valve on a two-valve unit or heat valve on a dehumidification
unit.
K2 – Heating Relay
K3 – Alarm Relay
K4 – Compressor Relay
K5 – Low Fan
K6 – High Fan
Each of these relays have, in parallel, a green LED indicator that lights up when the relay is
energized.
The circuit board incorporates digital inputs that are opto-coupled to a 24V AC source. These have
amber LED indicators located near the input locations which are lit when the input is closed. The
inputs include:
High Pressure Switch
Low Pressure Switch
Heat Call (W on thermostat terminal)
Cool Call (Y on thermostat terminal)
Fan Call (G on thermostat terminal)
Auxiliary (A on thermostat terminal)
Compressor shutdown (24V AC signal thru O/O). Providing a continuous 24V potential to
O/O will terminate and prevent compressor operation. This can be used for duty-cycling,
minimizing power consumption during an emergency power period or during sufficiently
low outdoor air temperatures which allow for free cooling – all while maintaining the
heating function.
Unit shutdown (24V AC signal thru A/O). Providing a continuous 24V AC potential to A/O
will terminate and prevent unit operation. This can be used for a night shutdown. On both
arrangements a single 24V AC signal can shutdown many units. ¼ VA is required per unit.
Finally, the board has four analog inputs provided via thermistors. These inputs are as follows:
Ta – Discharge Air Temperature
Tr – Refrigerant Temperature
Tw – Outgoing Water Temperature
Co – Condensate Level
