Varmeteknikk AS August 2017 e-mail: post@varmeteknikk.no
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Maintenance
NOTE!
BEFORE SERVICE AND MAINTENANCE, BE SURE SUPPLY CABLES ARE DEAD.
Always use an appropriate voltage detector to verify that there is no voltage present.
After boiler has been in operation for some time, retighten electrical connections. To prevent
breakdown, boiler should be checked annually. This check should contain the following points:
- Leakage control
Make a visual inspection of the boiler checking for signs of water leakage. Remove top cover
and check on top of the pressure vessel for leakage from heating elements.
- Power checking
Check if circuit breakers have tripped. Check by resistance measurement if any heating elements
are broken.
- Contactors
Check all individual contactors if they are in normal position. Undertake a visual inspection of
all wiring to the contactors and check for signs of overheating or burning. Any noise from contactor indicates wear and requires a thorough check. Be aware that burnt contactors may cause
major damage.
- Electrical connections
Retighten all electrical connections on fuse holders, contactors and heating elements.
- Temp.controller
Check if temp.controller connect or disconnect power steps when adjusting preset temp. up and
down. By entering service menu connection of power groups/contactors can be checked.
- Safety temp.limiter
Check safety temp.limiter. This can be done by switching off circulation pump or close valves.
The boiler will then soon reach release temp. Safety temp. limiter must be manually reset.
Note!
SERVICE AND MAINTENANCE SHOULD ONLY BE CARRIED OUT BY QALIFIED PERSONNEL
Tightening torques for contactors:
Contactor, type Connection screw Tightening torque
AF9, AF12, AF 16 M3,5 1,5Nm
AF26, AF30, AF 38 M4 2,5Nm
AF40, AF52, AF 65 M6 4Nm
Tightening torques for circuit breakers:
type Connection screw Tightening torque
MS132/10 M3,5 1,2Nm
MS132/12 - 16 M4 1,5Nm
MS132/20 - 32 M4 2Nm
XT1 M6 6Nm
Tightening torque for heating element: M4 - 1,2Nm
M12 - 15Nm