General information
16
VALVE MAINTENANCE
The valve is a very delicate mechanism, so the system operator must check its efficiency. If necessary, contact a technician
authorised by the manufacturer.
It is good practice for the safety valves installed to protect the plant:
–
to be operated (once a week) with system pressurised, by activating the manual lifting lever of the shutter
–
to have their calibration checked once a year, directly on the system or with bench test
–
to be subjected to overhaul every two years
–
to be replaced after ten years of operation
m
IMPORTANT
The safety valves are designed and built to operate without lubricant; simply keep them clean and efficient. Always
refer to the specific manual.
SAFETY MIN-MAX PRESSURE SWITCHES
The pressure switch features a unipolar switch whose contact’s position depends on the pressure found on the relevant connection
and on the set value.
The max safety pressure switch is set at a pressure higher than the maximum one of the pressure transducer, but always lower
than safety valve opening value.
The minimum pressure must be calibrated at a pressure higher than the water saturated steam pressure at the operating
temperature in order to ensure that the boiler body only contains water in a liquid state.
The safety pressure switches are triggered in case of pressure transducer fault and stops the burner permanently.
The burner will be switched on again only after the water pressure value has decreased and the control panel has been manually
reset.
NOTE
Calibration and sealing at the manufacturer’s premises
For further information, see the specific instructions supplied with the boiler.
SAFETY THERMOSTAT
The safety thermostat stops the burner when the required temperature value is reached and sends an alarm signal.
The restart is performed only after the alarm cause has been removed and the system has been reset by using the reset button
on the control panel.
NOTE
Calibration and sealing at the manufacturer’s premises
For further information, see the specific instructions supplied with the boiler.
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz
