R e s i d e n t i a l S p l i t - 6 0 H z R 2 2 & R 4 1 0 A
R e v. : 5 J u n e , 2 0 0 8
32
W a t e r- S o u r c e H e a t i n g a n d C o o l i n g S y s t e m s
Electrical - Low Voltage Wiring
From Water Source
IN
OUT
NOTE: Shut-off valves, strainers and
other required components not shown.
Solenoid
Valve
Flow
Regulator
To Discharge
Stage 1
Stage 2
Figure 27: Two-Stage Piping
ELECTRICAL - THERMOSTAT WIRING
Thermostat Installation
The thermostat should be located on an interior wall in a
larger room, away from supply duct drafts. DO NOT locate
the thermostat in areas subject to sunlight, drafts or on
external walls. The wire access hole behind the thermostat
may in certain cases need to be sealed to prevent erroneous
temperature measurement. Position the thermostat back
plate against the wall so that it appears level and so the
thermostat wires protrude through the middle of the back
plate. Mark the position of the back plate mounting holes
and drill holes with a 3/16” (5mm) bit. Install supplied
anchors and secure plate to the wall. Thermostat wire
must be 18 AWG wire. Wire the appropriate thermostat as
shown in Figures 28a and 28b to the low voltage terminal
strip on the CXM control board. Practically any heat pump
thermostat will work with these units, provided it has the
correct number of heating and cooling stages.
Y
O
G
R
C
Y
O
G
R
C
W1
W2
W
E
Typical
Air Handler
Typical
T-stat
CXM Board
(Compressor
Section)
O
Y/Y2
G
R
C
L
AL1
Optional
Jumper
Y
O
G
R
C
Y1
O
G
R
C
W1
W2
W
E
Typical
Air Handler
Typical
T-stat
CXM Board
(Compressor
Section)
O
G
R
C
L
AL1
Y2
Y1
Y/Y2
From Compressor
Solenoid Valve
Figure 28b: Typical Thermostat Wiring, Single-Stage
Units (2 Heat/1 Cool)
Figure 28a: Typical Thermostat Wiring, Two-Stage Units
(3 Heat/2 Cool)
CAUTION!
CAUTION!
Refrigerant pressure activated water regulating
valves should never be used with Carrier Geothermal
equipment.
CAUTION!
CAUTION!
Many units installed with a factory or
fi
eld
supplied manual or electric shut-off valve.
DAMAGE WILL
OCCUR
if shut-off valve is
closed
during unit operation. A
high pressure switch must be installed on the heat pump
side of any
fi
eld provided shut-off valves and connected to
the heat pump controls in series with the built-in refrigerant
circuit high pressure switch to disable compressor operation
if water pressure exceeds pressure switch setting. The
fi
eld
installed high pressure switch shall have a cut-out pressure
of 300 psig and a cut-in pressure of 250 psig. This pressure
switch can be ordered from Carrier Geothermal with a 1/4”
internal
fl
are connection as part number 39B0005N02.