Fill Low Water Pressure; Lockout And Error Code Descriptions - NTI Trinirt TX series Operating Instructions Manual

Tx Series
Fill – Low Water Pressure
The Tx boiler is equipped with a water pressure sensor located in the return piping inside the boiler cabinet, see
Figure 19-1(d), item 24 for sensor location; the reading from the sensor is displayed on the Main Screen, see
Figure 17-2. If the control senses a pressure below 7psi, burner operation is inhibited and "FILL" is displayed on
the screen, see Figure 17-7. As long as the water pressure is above 3psi the circulators will be permitted to
operate; otherwise they are only operated 5 seconds every minute.
Water Pressure
Table 17-3 Lockout and Error Code Descriptions
Code Description
Ignition Error – three unsuccessful ignition attempts in a row; perform the following checks:
Loc 1
1. Check venting for blockages.
2. Check condensate trap from proper draining.
Static gas pressure – if insufficient check gas supply-lines and regulator.
3.
4. Gas pressure during ignition – if the static gas pressure is sufficient, check pressure during ignition
sequence, i.e. when gas valve opens.
a. If pressure drops below minimum (4" for NG / 8" for LP), check gas supply-line and regulator.
b. If pressure does not move, verify 120VAC at valve during ignition; if no power, check wiring
c. If pressure drops slightly – proceed to next step
Unit ignites but immediately goes out – check flame sensor (clean or replace) and flame sensor
5.
cable, clean combustion chamber, replace control. If a combustion analyzer is available, adjust
throttle screw out 1 turn – check/adjust combustion once unit is operational.
Unit fails to ignite – check spark electrode and cable (replace). Verify the spark electrode is
6.
arcing. WARNING!! – maintain clearance from ignition components while the power is on to
avoid risk of severe electrical shock.
Unit ignites and runs – check combustion at maximum and minimum modulation rates.
7.
Gas Valve Circuit Fault (Safety) – control has sensed a fault in the gas valve electrical circuit, check for a
Loc 2
loose connection in the gas valve wiring harness. Also see "Loc 5".
Controller Malfunction – contact NTI, replace controller.
Loc 3-4
Limit Circuit Open (Safety) – control has sensed a fault in the safety limit circuit; check the following:
Loc 5
External Limit (Purple wire) – if an external limit device (i.e. LWCO) is connected to the purple
1.
wire at the field wiring terminal, check to ensure it has not tripped, and that it is wired correctly.
Internal Limit (Heat Exchanger Thermal Fuse) – the heat exchanger is equipped with a normally
2.
closed thermal fuse; the fuse opens when the heat exchanger gets too hot. If the fuse is open,
contact NTI [see Figure 19-1(a), item 48].
Controller Malfunction – contact NTI, replace controller.
Loc 6-9
Supply Sensor Fault – controller has sensed an invalid reading at the Supply/Outlet sensor; check cable,
Loc 10
then replace sensor [see Figure 19-1(a), item 15].
Uncorrected Blocking Error – a blocking error (Err) has lasted for 20 consecutive hours.
Loc 11
Incorrect Fan Speed – measured fan speed is not reaching target fan speed within 60 seconds. Check
Loc 12
wiring to fan, replace fan.
Controller Malfunction – contact NTI, replace controller.
Loc 13-26
Flame present 10 seconds after closing gas valve – verify flame is going out immediately following the
Loc 27
end of a burner demand; check flame sensor (replace); check condensate drain for blockages; increase post
purge setting (Installer Menu setting 2-30).
Figure 17-7 Fill – Low Water Pressure
– replace control; if power is present – replace gas valve.
Installation and Operation Instructions
│
Trinity
FILL – indicates the
water pressure is too
low.
69