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page no. 40 of 44
NVx Range Users, Installation & Servicing Instructions issue 6.4 Aug 2017.
Start
Yes
No
Yes
No
Yes
will not
Reset
No
Yes
absent
No
Present
Faulty limit interlock relay
Absent
Yes
Failed
OK
230V between 1 & 2 (CON5) on Pactrol control ?
Absent
Yes
Absent
Yes
OK
Absent
Yes
No
Yes
No
Yes
No
Yes
No
Yes
Yes
No
230V between 2 & 3 (CON5) on Pactrol control?
good. Faulty Limit Interlock relay
Failed
Check for 230V at terminal 1 of the terminal strip
External control circuit not calling for heat
Check Fuse "L"
Limit thermostat tripped
(Red light on front
panel On) Internal reset
Press Red reset switch internal panel when unit is
cool. If it will not reset when cold check for for 230V
between terminals 9 & 11 on the limit interface board
Check
faul ty l i mi t s tat
Gas & Electrical supplies present
Unit at Lockout (Lockout lamp on low
level controls and Amber light on front
panel/ internal control panel alight)?
on low level controls or the
switch. Faulty Pactrol control
Checked the set points. External control in fan mode?
230V at APS terminal C ?
Adjust the APS set point. Change the APS
230V at APS Terminal NO
Check for 230V between
8 & 9 on the terminal
strip
Exhaust fan runs?
Absent
Present
Faulty Exhaust
fan/and or capacitor
Pactrol control
Gas valve opens ?
230V between terminals 10
& 11 on the terminal strip
valve
Cont. next page
3.1 Fault Finding