4
4
subjected to local heat gain e.g.in front of
windows allowing the sun to act directly on
the thermostat.
Note: The main electric supply should be
protected by a fused isolating switch rated
at:-
GP-300
13 Amps
GP-400
10 Amps 3 Ph.
GP-500
10 Amps.3 Ph
GP-750
20 Amps 3 Ph
GP900
20 Amps 3 Ph
The wiring to the appliance should be to
I.E.E. Regulations. An earth wire is
connected to the main terminal block in the
heater, as indicated in the wiring diagrams.
8. Commissioning
Instructions
Ensure that the gas and electricity supplies
to the appliance are turned off. Set the
thermostat to a minimum position.
Switch on the main electrical supply. Select
the ‘manual’ setting on the fan/limit stat,
which will then start the fan. Now switch to
automatic. If the fan should fail to start, try
to establish the cause (e.g. the blowing of a
fuse or a fault in the wiring). Disconnect the
main electrical supply.
Refer to the Burner Supplement supplied
with the heater and complete gas
soundness test on the burner controls
assembly.
Complete the specified tests in the
Commissioning and Testing section of the
Burner Supplement. The following is a
description of the sequence of events that
will occur each time the external control
circuit is completed.
With all the controls on and the thermostat
calling for heat, the burner starts up going
through a pre-purge period before ignition
takes place. Start gas is released and
ignited. The flame is sensed by an ionisation
probe which allows the control box to open
the main gas valve thus establishing main
flame.
On loss of flame or breakdown of the
rectification systems the control box will go
to lockout, and the rest button located on
the control box will light up. Press the
lockout button in order to rest the control
box.
The burner motor drives a fan which
provides air for combustion. The air
pressure that this fan produces is sensed
and used to operate a pressure switch. This
in turn signals the control box that air
circulation is proved. Any loss in air
pressure will automatically result in the
burner going to lockout.
Fitted to the burner is the main gas
electrically operated valves.
9. Maintenance
Instructions
A maintenance check should be carried out
annually. The check should be for safe and
reliable operation of the burner and flue
system, and any wear likely to take place
on switches or moving components.
