NTI Trinity Tft399 Installation And Operation Manual page 67

Tft Series
Table 16-1 Troubleshooting Chart
PROBLEM
Hold 65 – Interrupted Air
Switch OFF
Hold 66 – Interrupted air
switch ON
Hold / Lockout 67 – ILK OFF
Lockout or Hold 79 – Outlet
High Limit
Lockout or Hold 81 – Delta T
limit
OR
Appliance making banging or
hissing sounds
Lockout 82 – Stack limit
Lockout or Hold 85 –
Inlet/Outlet Inversion Limit
Lockout or Hold 88 – Outlet
T Rise limit
Hold 91– Inlet sensor fault
Installation and Operation Instructions
POSSIBLE CAUSE
Incorrect Sola controller.
Incorrect Sola controller.
Low Water Condition
External Limit Tripped
Blocked Condensate Switch
CH or DHW settings
CH or DHW pump problem
Incorrect "Outlet high limit" setting
Incorrect "Outlet high limit
response" setting
Insufficient water flow
Dirty heat exchanger
Incorrect "Stack limit setpoint"
Faulty sensor
Pump flowing in the wrong
direction
Incorrect factory sensor wiring
Insufficient water flow
Sensor disconnected
CORRECTIVE ACTION
Replace control with correct model (Replacement
part number 77777).
Replace control with correct model (Replacement
part number 77777).
Check operation of internal LWCO.
Indication that an external limit (wired to "LIM")
is open. Not a problem with boiler, check external
limit.
Blocked Condensate Switch has opened –
condensate is not draining from the boiler, or the
exhaust venting is too restrictive or has a
blockage. Check for blockages in the condensate
trap and drain; clean accordingly. If drain is not
blocked, check for blockages/restrictions in the
exhaust venting, then clear the lockout.
If drain and venting are not blocked, then remove
vinyl tube from the condensate switch and check
contacts 1&2 for continuity; if open, replace the
switch.
Check if CH and/or DHW setpoint temperature
plus off hysteresis exceed "High limit" setpoint –
factory setting = 200°F (93°C).
"
See Inoperative CH or DHW pump
Increase "Outlet high limit" setting; maximum
setting = 200°F (93°C).
Unless deemed unacceptable by local installation
codes, the "Outlet high limit response" should be
set to "recycle and hold" to prevent lockout.
 Check Fuse
"B"
 Check appliance pump.
 Ensure plumbing is correct. Refer to Section
10.0 System Piping. Check that water pressure
is at least 15PSI.
 Boiler heat transfer surfaces may be fouled
with scale or magnetite. Clean with Fernox
DS-40 Descaler and Cleanser. See Table 10-1.
Inspect and if required clean the combustion
chamber and/or heat exchanger. Refer to Section
14.0 Annual Maintenance and Inspection and
Section 10.0 Boiler and Heating System Piping.
Unless installed in Canada with PVC exhaust
venting, set "Stack limit setpoint" to maximum
setting of 220ºF (104ºC). In Canada PVC exhaust
venting is limited to 149ºF (65ºC).
Check resistance of sensor and compare to
thermistor resistance chart, see Table 16-2.
Ensure water circulation through the boiler is in
the correct direction, see Figure 10-1.
Disconnect flue sensor cable; screen should
display "Hold 95 – Stack sensor fault"; if not
contact NTI.
See Lockout or Hold 81.
Check sensor connection located on the bottom of
the heat exchanger. Check connection on control
board.
│
Trinity
"
below.
67