Trane PRGD series Installation, Operation And Maintenance Manual page 22

S S e e q q u u e e n n c c e e o o f f O O p p e e r r a a t t i i o o n n s s
2. Open the regeneration solenoid valve and turn on
the carbon tank heater.
3. Monitor the carbon temperature until it reaches the
regeneration temperature value of 240°F (115.6°C),
and control within a ±10°F (5.5°C) dead band for
15 minutes (this step should take approximately
3 hours).
If the carbon tank temperature exceeds 120 percent of
the regeneration temperature setpoint, the controller
issues a latching diagnostic, Purge Carbon
Regeneration Temperature Limit Exceeded. The
purpose of this diagnostic is to identify a failed heater
relay or temperature sensor. It disables the purge and
opens the exhaust solenoid valve.
If the carbon tank temperature does not increase more
than 25°F (13.9°C) in the first two hours, the controller
generates a non-latching diagnostic, Carbon
Regeneration Temperature Too Low. The purpose of
this diagnostic is to identify a failed heater or
temperature sensor. It prevents automatic regeneration
from occurring, but a service technician can initiate a
manual regeneration for testing purposes. All other
purge algorithms continue to function.
If the carbon tank temperature does not reach the
minimum regeneration temperature setpoint within
four hours, the controller generates a non-latching
diagnostic, Purge Carbon Regen Temperature Not
Satisfied. The purpose of this diagnostic is to identify a
failing insulation system.
Consult "Carbon Regeneration Temperature Diagnostic
Procedure," p. 30, if a Carbon Regeneration
22
Temperature Setpoint Not Satisfied diagnostic or a
Carbon Regeneration Temperature Limit Exceeded
diagnostic is generated.
The complete regeneration cycle can take as long as
seven hours to accomplish but an average chiller does
not have to regenerate very often. A typical
regeneration cycle is depicted in the following figure.
Figure 11. Typical carbon regeneration cycle
PRGD-SVX01F-EN