Unigas C85A, Manual Of Installation - Use - Maintenance

PART II: INSTALLATION

22

Gas Proving System VPS504 (Option)

The VPS504 check the operation of the seal of the gas shut off valves. This check, carried out
as soon as the boiler thermostat gives a start signal to the burner, creates, by means of the
diaphragm pump inside it, a pressure in the test space of 20 mbar higher than the supply
pressure. 
When wishing to monitor the test, install a pressure gauge ranged to that of the pressure sup-
ply point 

PA

. If the test cycle is satisfactory, after a few seconds the consent light 

LC

 (yellow)

comes on. In the opposite case the lockout light 

LB

 (red) comes on. To restart it is necessary

to reset the appliance by pressing the illuminated pushbutton 

LB

.

Once the train is installed, connect the gas valves group and pressure switches plugs.

ELECTRICAL CONNECTIONS

Follow the electrical diagrams attached to the manual for the connections to the terminal strip.
The electrical panel is supplied complete with a terminal strip for the connection to the system electrical line and, in case of on board 
control panel, a plug for the connection to the modulation probe (if any).

Rotation of electric motor

Once the electrical connection of the burner is executed, remember to check the rotation
of the electrical motor (pump motor if any, and fan motor) . The motor should rotate accor-
ding to the “arrow” symbol on the body. In the event of wrong rotation, reverse the three-
phase supply and check again the rotation of the motor.

NOTE: the burners are supplied for three-phase 380 V or 400 V supply, and in the case of three-phase 220 V or 230 V supply it
is necessary to modify the electrical connections into the terminal box of the electric motor and replace the overload tripped
relay.

WARNING: (only for double stage and progressive burners) The burner is provided with an electrical bridge 

between terminals 6 and 7; when connecting the high/low flame thermostat, remove this bridge before connecting 

the thermostat.

Any cable connection or hook-up to the grid must be carried out by qualified, informed and trained personnel, 

directly coordinated and authorized by Technical Service. Always check in advance that the system electrical 

interlock is fitted with a safety circuit breaker.

WARNING! It is forbidden to use the fuel pipes for the execution and/or completion of the grounding



The system must comply with the current regulations.



Earth the system; always check in advance the connection, functionality and compliance with the health and safety principles of the earth
cable. If in doubt, ask for an accurate inspection by qualified technical engineers.



Check the connection to the grounding system.



Do not use any extraneous conductive parts (i.e. fuel feeding pipes, metal structures ...) to connect the burner to ground.



In connecting the supply wires to the burner MA terminal strip, ensure that the earth wire is longer than the phase and neutral wires.



Careful not to invert the phase and neutral connections



Fit the burner power line with an omnipolar disconnector and differential switch, a thermo-magnetic circuit breaker or fuses.



Supply the burner with a flame retardant cable with a section suitable to the installed power (see electrical diagram enclosed), paying
attention to the voltage values printed on the burner plate.



Always check in advance the protection from overcurrents and electromagnetic interference of the power supply. If these and other values
do not match the threshold data stated by the manufacturer, isolate the burner from all power sources and contact the Authorized Techni-
cal Service urgently. 



Check that the voltage of the system and burner motors match the voltage of the power grid (+/- 10%). 



Ensure the IP protection rating is consistent with the installation place and environment characteristics 



Before carrying out any operation on the machine electrical panel, open the system omnipolar disconnector and move the switch on the
burner panel to OFF.

In any case:



use suitably protected and safe burner/boiler supply and tracking cables;



avoid using extensions, adaptors or multiple sockets.

For further information, refer to the electrical diagram.

ATTENTION: check the calibration of the thermal relay sensor (+5% ÷
+10% rated value).

DANGER! Incorrect motor rotation can seriously damage property and injure people.

LC
LB

PA