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Installation- electrical, Pressure switch – Trane GSSD User Manual

Page 13

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13

Pressure Switch

A high pressure switch is provided to

protect the compressor against exces-
sive refrigeration pressure. The low

pressure switch should be wired in ac-

cordance with the type of freezestat
that is used. Trane factory supplies

two low pressure switches in the re-

frigerant circuit. The electrical con-
nection is dependant upon which

freezestat (35 or 20 degree) is selected

The pressure switch is used to protect
the compressor against operation un-

der low charge or catastrophic loss of

charge situations.
The low water temperature switch is

provided to protect the water-to-re-
frigerant heat exchanger from freez-

ing. This device triggers the lock out

relay when leaving water temperatures
fall below the preset freezestat setting.

This device may be reset by cycling

power, but the system should be re-
viewed for operational error.

Important Notice

The low pressure switch should be
wired to activate at refrigerant
pressures of 35 psig when a 35
degree F freezestat is used; 7 psig
when a 20 degree F freezestat is
used. The installer should verify
that the correct freezestat and low
pressure switch are used in your
application. Misapplication can
produce a failure to the unit and
cause the warranty to be voided.

Installation- Electrical

35-DEGREE F

OR

20-DEGREE F
FREEZESTAT

WATER-OUT

WATER-IN

LIQUID LINE

SUCTION-DISCH

HEAT EXCHANGER

EXPANSION VALVE

FILTER DRIER

DESUPERHEATER

DESUPERHEATER PUMP

COMPRESSOR

LINE

DESUPERHEATER-OUT

DESUPERHEATER-IN

REVERSING VALVE

35 PSIG LOW PRESSURE
SWITCH USED FOR 35
DEGREE FREEZESTAT

7 PSIG LOW PRESSURE
SWITCH USED FOR 20
DEGREE FREEZESTAT