Page 27
XP19 SERIES
TEST
Placing the jumper on the test pins allows the technician to:
S
Clear short cycle lockout
S
Clear five−strike fault lockout
S
Cycle the unit in and out of defrost mode
S
Place the unit in defrost mode to clear the coil
When Y1 is energized and 24V power is being applied to the Demand Defrost Control, a test cycle
can be initiated by placing a jumper on the Demand Defrost Control’s TEST pins for 2 to 5 seconds.
If the jumper remains on the TEST pins for longer than five seconds, the Demand Defrost Control
will ignore the jumpered TEST pins and revert to normal operation.
The control will initiate one test event each time a jumper is placed on the TEST pins.
For
each TEST the jumper must be removed for at least one second and then reapplied.
DEMAND DEFROST CONTROL
(UPPER LEFT−HAND CORNER)
JUMPER
NOTE Placing a jumper on the TEST pins will not bring the unit
out of inactive mode. The only way manually activate the heat
pump from an inactive mode is to cycle the 24VAC power to the
Demand Defrost Control.
Y1
Active
Place a jumper on TEST pins for
longer than one second but less
than two seconds.
Clears any short cycle lockout and
five strike fault lockout function, if
applicable. No other functions will be
executed and unit will continue in the
mode it was operating.
Place a jumper on TEST pins for
more than two seconds
.
Clears any short cycle lockout and
five strike fault lockout function, if
applicable.
If in
HEATING
Mode
If in
DEFROST
Mode
No further test mode operation will be
executed until the jumper is removed
from the TEST pins and reapplied.
If no ambient or coil sensor ault exist,
unit will go into DEFROST MODE.
If ambient or coil faults exist (open or
shorted), unit will remain in HEAT
MODE.
The unit will terminate defrost and
enter HEAT MODE uncalibrated
with defrost timer set for 30 minute
test.
If jumper on TEST pins remains in
place for more than five seconds.
The unit will return to HEAT MODE
un
−
calibrated with defrost timer set
for 30 minutes.
If jumper on TEST pins is removed
before a maximum of five seconds.
The unit will remain in DEFROST
MODE until termination on time or
temperature.
O
Line Status
INACTIVE
ACTIVE
If in
COOLING
Mode
Figure 36. Test Mode
