Trane UV-SVN02B-EN, Installation Operation & Maintenance, Page: 47 / 52

UV-SVN002-EN 47
Troubleshooting
Trouble Shooting Analysis
WARNING:
Hazardous Service Procedures!
The maintenance and troubleshoot-
ing procedures recommended in
this section of the manual could
result in exposure to electrical,
mechanical or other potential safety
hazards. Always refer to the safety
warnings provided throughout this
manual concerning these proce-
dures. When possible, disconnect all
electrical power including remote
disconnects before servicing. Follow
proper lockout/tagout procedures to
ensure the power can not be inad-
vertently energized. When necessary
to work with live electrical compo-
nents, have a qualified licensed elec-
trician or other individual who has
been trained in handling live electri-
cal components perform these tasks.
Failure to follow all of the recom-
mended safety warnings provided,
could result in death or serious
injury.
If operating difficulties are encoun-
tered, refer to the following for
probable causes and corrective
measures. If suggested corrective
measures have been taken, and the
trouble still persists, contact the
control supplier or the local Trane
Sales Office.
Heating
A. Room Too Warm --- Outside
Temperature Below 35 F.
1. Check the room thermostat to
make sure it is properly set.
2. If this occurs during the early
part of the day, it may be due
to the room thermostat giving
a false reading caused by room
walls still being cold from the
night temperature setting. To
correct, start the warm-up cycle
earlier in the morning to give
the wall a chance to come up to
room temperature before the
room is occupied.
3. If the thermostat is mounted on
a cinder block wall, the hole in
the cinder block could cause
cool air through the hole to
affect the thermostat. In this
case, the thermostat may need
to be relocated.
4. Check for proper operation of
the face and bypass damper or
coil control valve. If the damper
or valve appears to be function-
ing improperly, contact the
control contractor or, if Trane
controls, see
CNT-SVX04A-EN
(Tracer TM ZN520 Unit Controller
IOP) for details on DDC
controls.
B. Room Too Warm --- Outside
Temperature Above 35 F.
1. Check the room thermostat to
make sure it is properly set.
2. Check for proper operation of
the face and bypass damper or
coil control valve. If the damper
or valve appears to be function-
ing improperly, contact the
control contractor or, if Trane
controls, see
CNT-SVX04A-EN
(Tracer TM ZN520 Unit Controller
IOP) for DDC controls details.
3. Check the outside air damper.
The outside air damper should
be in the open position.
4. Check for a clogged filter. If the
filter is clogged, the restriction
of air flow may seriously
reduce the ventilation capacity
of the unit. Clean or replace the
filter.
5. If the installation utilizes
Wall-Fin auxiliary radiation:
a.
Hot Water --- if control of
water flow is provided, check
the control valve for proper
functioning.
b. Boiler --- Check the boiler
reset schedule to determine
if the loop temperature can
be decreased.
c. Steam --- Check the
operation of the control
valves.
6.
Check the outside air tempera-
ture --- is it above 60-65 F?
The economics of the Unit
Ventilator selection dictate that,
in most cases, the unit will be
sized to provide adequate
natural (ventilation) cooling
with outside temperatures up
to 60-65 F. Above this point, a
changeover should be made to
the mechanical cooling cycle.
C. Room Too Cool
1. Check the room thermostat to
make sure it is properly set.
2. Check the air filter. If clogged,
renew or replace.
3. Check for proper operation of
the face and bypass damper or
coil control valve. If the damper
or valve appears to be function-
ing improperly, contact the
control contractor or, if Trane
controls, see
CNT-SVX04A-EN
(Tracer TM ZN520 Unit Controller
IOP) for details on DDC
controls.
4. Check the outside air damper. It
should be closed or at a
minimum outside air setting.
5. On the hot water or steam type
units, check the boiler pressure
or temperature to make sure
that design requirements are
being met.
6.
If the installation utilizes Wall-
Fin auxiliary radiation:
Check the radiation controls for
proper operation.