28
C l i m a t e M a s t e r W a t e r- S o u r c e H e a t P u m p s
C L I M A T E M A S T E R W A T E R - S O U R C E H E A T P U M P S
Tr a n q u i l i t y
®
2 0 ( T S ) S e r i e s
R e v. : 0 6 / 1 7 / 1 5
Figure 18: LT1 Limit Setting
CXM PCB
LT1
LT2
JW3-LT1 jumper
should be
clipped for low
temperature
operation
Electrical - Low Voltage Wiring
Accessory Connections
A terminal paralleling the compressor contactor coil
has been provided on the CXM/DXM control. Terminal
“A” is designed to control accessory devices, such as
water valves. Note: This terminal should be used only
with 24 Volt signals and not line voltage. Terminal “A” is
energized with the compressor contactor. See Figure 19
or the specifi c unit wiring diagram for details.
Figure 19: Accessory Wiring
Low Voltage VA Ratings
Component
VA
Typical Blower Relay
6 - 7
Typical Reversing Valve Solenoid
4 - 6
30A Compressor Contactor
6 - 9
Subtotal
16 - 22
+ CXM board (5 - 9 VA)*
21 - 31
Remaing VA for Accessories
19 - 29
+ DXM board (8 - 12 VA)*
24 - 34
Remaing VA for Accessories
41 - 51
*Standard transformer for CXM board is 50VA.
Optional DXM board and/or DDC controls
include 75VA transformer.
Figure 20: AVM Valve Wiring
Figure 21: Taco SBV Valve Wiring
C
C
Thermostat
Y1
1
2
3
Y1
AVM
Taco Valve
Heater Switch
Water Solenoid Valves -
An external solenoid valve(s)
should be used on ground water installations to shut off
fl ow to the unit when the compressor is not operating. A
slow closing valve may be required to help reduce water
hammer. Figure 19 shows typical wiring for a 24VAC
external solenoid valve. Figures 20 and 21 illustrate
typical slow closing water control valve wiring for Taco
500 series (ClimateMaster P/N AVM) and Taco SBV
series valves. Slow closing valves take approximately
60 seconds to open (very little water will fl ow before 45
seconds). Once fully open, an end switch allows the
compressor to be energized. Only relay or triac based
electronic thermostats should be used with slow closing
valves. When wired as shown, the slow closing valve will
operate properly with the following notations:
1. The valve will remain open during a unit lockout.
2. The valve will draw approximately 25-35 VA through
the “Y” signal of the thermostat.
Note: This valve can overheat the anticipator of an
electromechanical thermostat. Therefore, only relay
or triac based thermostats should be used.
