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Symptom
Possible causes
Action
Damper closed and cannot be reset open
Thermal link has activated
Check thermal link by comparing with figures 1 and 2, page 3
If activated thermal links must be replaced
See below: 'Thermal link replacement'
Handle mechanism not engaged
on thermal link correctly
Check machine screw in spindle cap is tightly screwed down
Test handle hard to pull
Lack of lubrication
Remove handle mechanism, sparingly apply viscous lubricant to
region of spindle where handle slides, refit handle mechanism
See below: ‘Handle mechanism removal and replacement’
Damper blade not fully opening or closing
Damper motion obstructed by
debris
Remove debris.
Ensure no damage has been caused to damper.
Handle mechanism fitted
incorrectly
Remove and refit mechanism correctly
See below: Handle mechanism removal and replacement
procedure'
Ensure no damage has been caused to damper
Damper seized
Lubrication required
See below: 'Lubrication procedure'
Mechanical failure
Contact HVC
Damper blade loose
Mechanical failure
Contact HVC
Installation guide: NCA Series 400 hand operated single blade leakage rated fire damper
Operation and maintenance manual
Page 2 of 3 - Issue A - 03/03/2022
Thermal link replacement
1. Remove handle mechanism as per steps 1 - 3 of ‘Handle
mechanism removal and replacement procedure’ adjacent.
2. Remove activated link (12mm spanner required) and discard.
3. Refit new link ensuring correct temperature rating is used,
68°C (red bulb in link) or 93°C (green bulb in link).
4. Refit handle mechanism as per step 4 of ‘Handle mechanism
removal and replacement procedure’ adjacent.
5. Open damper as per step 8 of the periodic maintenance
procedure.
Troubleshooting
Additional procedures
Handle mechanism removal and replacement
1. Ensure damper is closed (setting handle perpendicular with
damper case).
2. Referring to page 3, figure 3 if necessary, unscrew the
machine screw in the shaft end cap (pozi-drive screwdriver
required).
3. Slide spindle cap, compression spring, test handle and setting
handle off shaft.
4. To refit, reverse previous steps, ensuring setting handle is
replaced perpendicular to damper case.
Contact HVC if the above does not solve your problem.
Lubrication
1. Remove access door/s to access the inside of ductwork and
damper blade.
2. Clean damper if required following step 7 of the periodic
maintenance procedure.
3. Apply a small amount of light oil (WD40 spray grease
recommended) directly into the blade axle bushes.
4. Remove any excess oil with a cloth.
5. Conduct a cycle test as per steps 7 and 8 of the periodic
maintenance procedure and observe whether the operation
has improved.
