Harry Taylor HT2000, Руководство пользователя

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Connection from the supply to the heater
must also comply with the relevant
regulations and must have been purged and
soundness tested by an authorised engineer.
3.3 Ignition sequence
PRE START DRY RUN
In order to test that all controls are in good
working order, the control sequence should
first be tested with the gas supply turned
Off .
Ensure gas isolating cock is in the Off
position.
Warning
If during the following sequence of
operations the heater fails to operate
correctly the fault should be traced and
rectified before proceeding, if necessary
referring to section 5.0 fault diagnosis.
a)
Switch off the main electrical supply to
the heater.
b) Turn off gas supply to the heater.
c) Open side panel, and connect
manometers to the gas supply test point and
to the main burner test point.
d) Ensure outlet louvres are correctly set.
e) Ensure fan rotation is not impaired or
obstructed.
f) Set room thermostat to its lowest setting.
g) If a time switch is fitted ensure it is set to
an on period.
h) Switch on electrical supply.
i) Use leak tester to test for soundness on
the unions and pipework.
j)
Operate the heater through the installed
control system.
On start the signal will activate the flue
venter for a pre purge period and in turn will
make the air proving switch, once made, the
air proving switch will complete the circuit to
the control box and after a 30 second Delay
the automatic control should attempt light the
burner, because the gas is turned off and
flame cannot be established , the control box
will go to LOCKOUT.
k) Reset the control on completion of dry run.
l) Open gas cock.
m) Operate heater through installed control.
The flue venter will pre purge the heater and
in turn operate an air proving switch which
completes the electrical circuit to the control
box, after a 30 second Delay the control will
open the gas solenoid valve and the main
burner will light.
The flame can be observed at the burner
manifold, check that the burner is providing a
good flame i.e. even and stable.
n) Check pressure readings on the
manometers, and continue to let the heater
fire for ten minutes.
o) When the fan starts ensure that the
direction of rotation is correct , and that the
fan start is within 2 minutes of burner ignition.
Caution
If the fan fails to operate within approximately
2 minutes and the heater goes to overheat it
will shut down through breaking the circuit to
the gas valve, the cause must be ascertained
and rectified before re-ignition.
Once the limit thermostat has tripped out it
must be manually reset to allow re-ignition to
take place.
p) After ten minutes check burner head
pressure is as specification - adjust as
necessary by removal of the gas pressure
adjustment cover, and using a screwdriver
turn the adjustment screw on the governor as
follows: Clockwise to increase, anti-
clockwise to decrease.
For Hi/Low and Modulation adjustment, refer
to the following procedures.