KlassKeeper – Installation, Operation, and Maintenance Manual
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© Copyright 2013 CGC Group Inc.
Last Revised April 2020 Installation, Operation, and Maintenance Manual is Subject to Change without Notice.
Operating Modes
The KlassKeeper heat pump has several modes of operation including: heating, cooling (first stage),
cooling (second stage), and fan. The unit is also equipped with an energy recovery ventilator (ERV). Each
of these modes of operation is invoked by closing the associated digital input on the internal unit
controller or via BAS, third party controller or thermostat.
Heating
In order to put the unit into heating mode, contact DI1 on the unit controller must be closed through a
dry contact on the thermostat or the unit-mounted third party controller by others or BAS. This will first
activate the main fan in low-speed, followed by high-speed if the heat call remains in place for 10 minutes
or more. A modulating heat valve that controls the flow of hot water through the unit’s heating coil is
opened 100% whenever a heat call is in place.
Cooling
In order to put the unit into cooling mode, contact DI2 on the unit controller must be closed through a
dry contact on the thermostat or the unit-mounted third party controller by others. This will activate the
fan in high speed, and will also start the first stage of the compressor for cooling. A cooling valve that
directs water to the condenser will also be opened whenever there is a cool call in place.
To bring on the second stage of cooling, contact DI3 on the unit controller must be closed through a dry
contact on the unit mounted third party controller by others. In order for second stage cooling to
commence, first stage cooling must first be activated.
Note that each compressor stage has a minimum off-time of one minute between calls. There is no
minimum on-time.
During cooling operation, if the fresh air entering temperature (FRSH-EAT) is cooler than the exhaust
entering air temperature (EX-EAT) by 5°F or more, the heat wheel will be deactivated to allow “free
cooling” to take place.
Fan
The main fan can be activated in low speed at any time by closing contact DI4 on the unit controller
through a dry contact on the unit mounted third party controller by others. If there is a heat or cool call
in place, the operation of the fan is automatic.
Energy Recovery Ventilator (ERV)
The KlassKeeper heat pump is equipped with an energy recovery ventilator that brings in fresh outside
air, while simultaneously exhausting indoor air. A heat wheel is used to pre-condition the incoming fresh
air, by recovering/rejecting heat from/to the outgoing exhaust air.
To activate the ERV function, digital input DI5 on the unit controller must be closed through a dry-contact
on the unit-mounted third party controller by others. This will activate both the ERV fan as well as the
main fan (in low speed), while also energizing the heat wheel. The hot water valve modulates to maintain
the discharge air temperature of 72
o
F (adjustable on the display or BAS)