Quick Start Manual
27
Installation, Operation & Maintenance  HTV/HTD/HTH SERIES  Heat Controller, Inc.
CXM Control
For detailed control information, see CXM Application, Operation 
and Maintenance (AOM) manual (part #97B0003N12).
Field Selectable Inputs
Test mode: Test mode allows the service technician to check 
the operation of the control in a timely manner. By momentarily 
shorting the test terminals, the CXM control enters a 20 minute 
test mode period in which all time delays are sped up 15 times. 
Upon entering test mode, the status LED will fl ash a code 
representing the last fault. For diagnostic ease at the thermostat, 
the alarm relay will also cycle during test mode. The alarm relay 
will cycle on and off similar to the status LED to indicate a code 
representing the last fault, at the thermostat. Test mode can be 
exited by shorting the test terminals for 3 seconds.
Retry Mode: If the control is attempting a retry of a fault, 
the status LED will slow fl ash (slow fl ash = one fl ash every 2 
seconds) to indicate the control is in the process of retrying.
Field Confi guration Options
Note: In the following fi eld confi guration options, jumper wires 
should be clipped ONLY when power is removed from the CXM 
control.
Water coil low temperature limit setting: Jumper 3 (JW3-FP1 Low 
Temp) provides fi eld selection of temperature 
limit setting for FP1 of 30°F or 10°F [-1°F or -12°C] (refrigerant 
temperature).
Not Clipped = 30°F [-1°C]. Clipped = 10°F [-12°C].
Air coil low temperature limit setting: Jumper 2 (JW2-FP2 Low 
Temp) provides fi eld selection of temperature limit setting for 
FP2 of 30°F or 10°F [-1°F or -12°C] (refrigerant temperature). 
Note: This jumper should only be clipped under extenuating 
circumstances, as recommended by 
the factory.
Not Clipped = 30°F [-1°C]. Clipped = 10°F [-12°C].
Alarm relay setting: Jumper 1 (JW1-AL2 Dry) provides fi eld 
selection of the alarm relay terminal AL2 to be jumpered to 24VAC 
or to be a dry contact (no connection).
Not Clipped = AL2 connected to R. Clipped = AL2 dry contact 
(no connection).
DIP Switches
Note: In the following fi eld confi guration options, DIP switches 
should only be changed when power is removed from the CXM 
control.
DIP switch 1: Unit Performance Sentinel Disable - provides fi eld 
selection to disable the UPS feature.
On = Enabled. Off = Disabled.
DIP switch 2: Stage 2 Selection - provides selection of whether 
compressor has an “on” delay. If set to stage 2, the compressor 
will have a 3 second delay before energizing. Also, if set for stage 
2, the alarm relay will NOT cycle during test mode.
On = Stage 1. Off = Stage 2
DIP switch 3: Not Used.
DIP switch 4: DDC Output at EH2 - provides selection for DDC 
operation. If set to “DDC Output at EH2,” the EH2 terminal will 
continuously output the last fault code of the controller. If set to 
“EH2 normal,” EH2 will operate as standard electric heat output.
On = EH2 Normal. Off = DDC Output at EH2.
NOTE: Some CXM controls only have a 2 position DIP switch 
package. If this is the case, this option can be selected by 
clipping the jumper which is in position 4 
of SW1.
Jumper not clipped = EH2 Normal. Jumper clipped = DDC 
Output at EH2.
DIP switch 5: Factory Setting - Normal position is “On.” Do not 
change selection unless instructed to do so by the factory.
CXM Controls
Short test pins 
together to enter Test 
Mode and speed-up 
timing and delays for 
20 minutes.
Figure 27: Test Mode Pins
Table 6a: CXM LED And Alarm Relay Operations
Description of Operation LED Alarm Relay
Normal Mode On Open
Normal Mode with UPS Warning On Cycle (closed 5 sec., Open 25 sec.)
CXM is non-functional Off Open
Fault Retry Slow Flash Open
Lockout Fast Flash Closed
Over/Under Voltage Shutdown Slow Flash Open (Closed after 15 minutes)
Test Mode - No fault in memory Flashing Code 1 Cycling Code 1
Test Mode - HP Fault in memory Flashing Code 2 Cycling Code 2
Test Mode - LP Fault in memory Flashing Code 3 Cycling Code 3
Test Mode - FP1 Fault in memory Flashing Code 4 Cycling Code 4
Test Mode - FP2 Fault in memory Flashing Code 5 Cycling Code 5
Test Mode - CO Fault in memory Flashing Code 6 Cycling Code 6
Test Mode - Over/Under
shutdown in memory
Flashing Code 7 Cycling Code 7
Test Mode - UPS in memory Flashing Code 8 Cycling Code 8
Test Mode - Swapped Thermistor Flashing Code 9 Cycling Code 9
-Flash code 2 = 2 quick fl ashes, 10 second pause, 2 quick 
fl ashes, 10 second pause, etc.
-On pulse 1/3 second; off pulse 1/3 second










