Trane Precedent TSC060, Installation Operation & Maintenance

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39
T_C-IOM-2A
Trouble Shooting
Simultaneous Heat and Cool Failure
1. Emergency Stop is activated
Method 2
The second method for determining sys-
tem status is done by checking voltage
readings at the RTRM (J6). The system
indication descriptions and the approxi-
mate voltages are listed below.
System Failure
Measure the voltage between terminals
J6-9 & J6-6.
Normal Operation = approximately 32
V D C
System Failure = less than 1 VDC, ap-
proximately 0.75 VDC
Test Mode = voltage alternates be-
tween 32 VDC & 0.75 VDC
Heat Failure
Measure the voltage between terminals
J6-7 & J6-6.
Heat Operating = approximately 32
V D C
Heat Off = less than 1 VDC, approxi-
mately 0.75 VDC
Heating Failure = voltage alternates be-
tween 32 VDC & 0.75 VDC
Cool Failure
Measure the voltage between terminals
J6-8 & J6-6.
Cool Operating = approximately 32
V D C
Cool Off = less than 1 VDC, approxi-
mately 0.75 VDC
Cooling Failure = voltage alternates be-
tween 32 VDC & 0.75 VDC
Service Failure
Measure the voltage between terminals
J6-10 & J6-6.
Clogged Filter = Approximately 32
VDC.
Normal = Less than 1 VDC, approxi-
mately 0.75 VDC Fan Failure = voltage
alternates between 32 VDC & 0.75
VDC.
To use LED’s for quick status information
at the unit, purchase a BAYSENS010B
ZSM and connect wires with alligator
clamps to terminals 6 through 10. Con-
nected each respective terminal wire (6
through 10) from the Zone Sensor to the
unit J6 terminals 6 through 10.
Note:
If the system is equipped with a
programmable zone sensor,
(BAYSENS019A, BAYSENS020A or
BAYSENS023A), the LED indicators will
not function while the BAYSENS010A is
connected.
Resetting Cooling and Heating
Lockouts
Cooling Failures and Heating Lockouts
are reset in an identical manner. Method
1 explains resetting the system from the
space; Method 2 explains resetting the
system at the unit.
Note:
Before resetting Cooling Failures and
Heating Lockouts check the Failure
Status Diagnostics by the methods
previously explained. Diagnostics will be
lost when the power to the unit is
disconnected.
Method 1
To reset the system from the space, turn
the “Mode” selection switch at the zone
sensor to the “Off” position. After ap-
proximately 30 seconds, turn the
“Mode” selection switch to the desired
mode, i.e. Heat, Cool or Auto.
Method 2
To reset the system at the unit, cycle the
unit power by turning the disconnect
switch “Off” and then “On”.
Lockouts can be cleared through the
building management system. Refer to
the building management system instruc-
tions for more information.
Zone Temperature Sensor (ZTS)
Service Indicator
The ZSM SERVICE LED is a generic in-
dicator, that will signal the closing of a
Normally Open switch at any time, pro-
viding the Indoor Motor (IDM) is operat-
ing. This indicator is usually used to indi-
cate a clogged filter, or an air side fan fail-
ure.
The RTRM will ignore the closing of this
Normally Open switch for 2 (±1) min-
utes. This helps prevent nuisance SER-
VICE LED indications. The exception is
the LED will flash 40 seconds after the
fan is turned “On” if the Fan Proving
Switch is not made.
Clogged Filter Switch
This LED will remain lit the entire time that
the Normally Open switch is closed. The
LED will be turned off immediately after
resetting the switch (to the Normally
Open position), or any time that the IDM
is turned “Off”.
If the switch remains closed, and the IDM
is turned “On”, the SERVICE LED will
be turned “On” again after the 2 (±1)
minute ignore delay.
This LED being turned “On”, will have no
other affect on unit operation. It is an indi-
cator only.
Fan Failure Switch
When the “Fan Failure” switch is wired to
the RTOM, the LED will remain flashing
the entire time the fan proving switch is
closed, indicating a fan failure, and it will
shut the unit operations down.
Zone Temperature Sensor (ZTS) Test
Note:
These procedures are not for
programmable or digital models and are
conducted with the Zone Sensor Module
electrically removed from the system.
Test 1
Zone Temperature Thermistor
(ZTEMP)
This component is tested by measuring
the resistance between terminals 1 and 2
on the Zone Temperature Sensor. Be-
low are some typical indoor tempera-
tures, and corresponding resistive val-
ues.