Trane RSDH0012 Manual Download

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Unit Controls and Sequence of Operation

SRV-SVX04B-EN

a. Fault and warning indication is seen in two possible

manners on the equipment’s control enclosure. The
HMI display and fault warning lights. The HMI will
display the blinking triangle with exclamation point
and the fault message on the Alarm screen



(Figure 3).

b. A fault results in the Red Light (LT02) remaining

illuminated constantly.

Figure 3.

2. List of System and DH Faults

a. FAULT - D/H WHEEL MOTOR STARTER

PROTECTOR TRIPPED
i. If the desiccant drive motor starter/protector

(MSP1) trips the system is faulted.

ii. The system will go into the shutdown sequence

as described in Section 4, and the system
auxiliary dry contacts close in sequence
(described in Section 2), also process blower
(optional) will purge.

iii. The dehumidifier will be held in the 'Fault'

condition by (PLC1). To restart the dehumidifier
clear the alarm pressing the acknowledge ACK
on the HMI, reset the overload, and go to the
ALARM screen and press the F4 RESET key this
resets the PLC. To restart the system, the
selector switch (SS01) must be moved to the
“OFF” position, then move (SS01) back to the
“AUTO” or “MANUAL” position.

b. FAULT - REACTIVATION MOTOR STARTER

PROTECTOR TRIPPED
i. If the reactivation blower motor starter/protector

(MSP2) trips the system is faulted.

ii. The dehumidifier goes into the shutdown

sequence, as described in Section 4, and the
system auxiliary dry contacts sequence as
described in Section 2 The dehumidifier will be
held in the 'Fault' condition by (PLC1). To restart
the dehumidifier clear the alarm pressing the
acknowledge ACK on the HMI, reset the
overload, and go to the ALARM screen and press
the F4 RESET key this resets the PLC. To restart
the system, the selector switch (SS01) must be
moved to the “OFF” position, then move (SS01)
back to the “AUTO” or “MANUAL” position.

c. FAULT - SUPPLY BLOWER MOTOR STARTER

PROTECTOR TRIPPED/ VFD FAULT (optional)

i. If the supply blower motor starter/protector

(MSP3) trips or the customer-supplied variable
frequency drive (VFD) goes into a Fault, the
system is faulted.

ii. The system will go into the shutdown sequence

(described in Section 4), and the system
auxiliary dry contacts close in sequence
(described in Section 2).

iii. The dehumidifier will be held in the 'Fault'

d. FAULT - DEHUMIDIFIER WHEEL ROTATION

i. Limit switch (LS01) is wired normally closed,

and is located inside the dehumidifier wheel
compartment next to desiccant wheel. As the
wheel turns, a cam fastened to the wheel
housing opens this limit switch.

ii. If limit switch (LS01) is not opened once every

600 seconds, a timer in (PLC1) times out the
system is faulted.

iii. The system will go into the shutdown sequence

(described in Section 4), and the system
auxiliary dry contacts close in sequence
(described in Section 2).

iv. The dehumidifier will be held in the 'Fault'

e. FAULT – REACTIVATION ELECTRIC HEATER

OVERTEMPERATURE
i. Temperature switch (TS01) is located in the

reactivation Electric Heater and is furnished to
detect extreme temperature level or heat
buildup.

ii. Temperature switch (TS01) is located in the

reactivation “Heated To” duct and is furnished
to detect extreme temperature level or heat
buildup.

iii. The system will go into the shutdown sequence

(described in Section 4), and the system
auxiliary dry contacts close in sequence
(described in Section 2).