349215-JIM-B-1008
Johnson Controls Unitary Products
21
nal, must be field wired to the building's VAV boxes to
ensure fully open dampers during heating operation.
OPTIONAL HOT GAS BYPASS (HGBP)
To allow for low cooling load operation, a direct-acting,
pressure-modulating bypass control valve installed on
the system #1 discharge line is used to divert high tem-
perature, high pressure refrigerant around the TXV in
order to maintain a desired minimum evaporator pres-
sure.
The opening pressure of the bypass valve is fully
adjustable between 0 and 80 psig with a factory-setting
of 60 psig. HGBP is standard on all units with VAV and
optional with CV units.
FIGURE 9 - ENTHALPY SETPOINT ADJUSTMENT
