SpaceKeeper Cons ole (SKC) – Ins tallation Operation Maintenance Manual
6
OPERATION
Fan Call (G on thermos tat terminal)
Auxiliary (A on thermos tat terminal)
Compres s or s hutdown (24V AC s ignal thru O/O). Providing a continuous 24V
potential to O/O will terminate and prevent compres sor operation. This can be
us ed for duty-cycling, minimizing power cons umption during an emergency power
period, or during s ufficiently low outdoor air temperatures which allow for free
cooling – all while maintaining the heating function.
Unit s hutdown (24V AC s ignal thru A/O). Providing a continuous 24V AC potential to
A/O will terminate and prevent unit operation. This can be us ed for a night
shutdown. On both arrangements a s ingle 24V AC s ignal can s hutdown many units .
¼ VA is required per unit.
Finally, the board has four analog inputs which can receive signals via thermis tors .
Thes e inputs are as follows :
Ta – Discharge Air Temperature
Tr – Refrigerant Temperature
Tw – Outgoing Water Temperature
Co – Condens ate Level
Ta, Tr, And Tw are 10k Ohm NTP thermis tors , while Co is a 100 Ohm NTP thermis tor.
Thes e inputs do not have LED indicators .
Fan
1. A fan call on “G” of the thermos tat terminal s trip activates relay K5 and caus es
the fan to operate at low-s peed on multi-s peed units .
2. A heat call on “W” of the thermos tat terminal s trip will als o caus e the fan to
operate at low-s peed. If the heating call is s till pres ent after a 10 minute
period, multi-s peed units will s witch the fan to high-s peed through the
activation of relay K6.
3. A cooling call on “Y” of the thermos tat terminal s trip will caus e the fan on
multi-s peed units to immediately s tep up to high-s peed through relay K6.
4. Fan operation is terminated when all calls are dropped.
5. When the fan is operating at high s peed, both relays are energized along with
their as s ociated LED indicators.
Heat Operation
A call on “W” for heat will activate the fan at low speed. It will als o
s imultaneous ly energize the heat relay K2 and its as s ociated LED. The relay K2
will provide 24V AC fus ed power directly to the heat valve.
