Zone
Zone
SEQUENCE OF OPERATIONS
VCB-X Controller Field Technical Guide
72
Water Source Heat Pump Operation
Water Source Heat Pump Operation
Cooling Mode will operate in the same manner as described in the
Cooling section.
A reversing valve relay output can be con
fi
gured to activate with
the
fi
rst compressor stage in the Heating Mode or the Cooling Mode
of operation.
In the Heating Mode, Auxiliary Heat can be used with Compressor
Heat to achieve the Active Supply Air Heating Setpoint. Auxiliary
Heat can be either modulating or staged forms of heat, or it can be
a modulating form of heat followed by staged heat.
When Auxiliary Heat comes on in conjunction with a digital
compressor heat stage, the digital compressor will be locked at
100% until the Supply Air Temperature (SAT) rises above the SAT
Heating Setpoint plus the Heat Staging Window. At that point, the
Auxiliary Heat will stage off (after a stage down delay) and the
digital compressor heat will be allowed to modulate.
Revised 4/9/12
Compressor lockouts are not used on a Water Source Heat Pump
Unit. There is no Dehumidi
fi
cation during Heat Mode of a Water
Source Heat Pump Unit. There is no Defrost Mode on a Water Source
Heat Pump Unit.
NOTE:
Any digital compressor stage in a Heat Pump unit must
be con
fi
gured as a “Digital Compressor”. The VCB-X
will know it will operate as a heat pump compressor
by the unit being con
fi
gured as having a Reversing
Valve. Any
fi
xed Heat Pump compressor stage must
be con
fi
gured as a “Heat Pump Compressor” rather
than a “Cooling Stage.”
The unit can be con
fi
gured for the percentage of glycol it has. The
options are 0%-40% in 5% increments.
