Rayburn Heatranger 368K Installation And Servicing Instructions - page 19
To Remove Airfan - See Fig. 26
a. Isolate the electricity supply (switch
OFF
and remove
plug), remove the side cover panel via its fixing screws.
Disconnect oil lines at burner inlets and depress
downwards for fan access. Remove cable lead connected
to terminal block position ‘
FAN
’ on sequential control box
- See Fig. 28.
b. Using box spanner, slacken and remove two top nuts
and also slacken two bottom locknuts and screws
securing mounting plate to boiler side.
c. Detach air pressure plastic tubes from air pressure
switch, + and -.
d. Tilt and lift complete fan assembly away from
appliance.
e. Remove the two screws securing the fan assembly to
the mounting plate.
CHECK THE GASKET SEAL IS INTACT AND
REPLACE IF NECESSARY.
f. Re-assemble in reverse order of dis-assembly and
reconnect electrical terminals.
The airfan is now ready for use.
To Remove Air Pressure Switch - See Fig. 26.
a. Isolate the electricity supply (switch
OFF
and remove
plug), remove the side cover panel via its fixing screws.
See Fig. 16.
b. Detach and remove plastic tubes from pressure
switch. + and -.
c. Remove three sleeved electrical terminations from
micro-switch noting order of connection.
d. Remove two fixing screws securing pressure switch to
strap.
NOTE: CHECK BOTH PLASTIC TUBES ARE
INTACT/AIRTIGHT AND REPLACE IF NECESSARY.
Replace switch assembly in reverse manner of dis-
assembly and remake electrical terminations.
Although the air pressure switch is now ready for use,
adjustments must be made to the switch for pressure
activation as follows:
i) Connect air pressure gauge to windox nipple.
ii) Switch
ON
, and initial cold start should indicate a cold
pressure reading of 3.1mm w.g. (0.125w.g.) which on hot
cycling should rise to a stable 4.1mm w.g. (0.165in w.g.).
With duct fully open 9-11mm w.g. across fan.
iii) Adjust excess air pressure via air pressure adjustment
flap on top of air duct, adjacent to fan.
To Remove Thermocouple Flame Sensor - See Fig. 16
a. Isolate the electrical supply (switch
OFF
and remove
plug) remove the side cover panel via its fixing screws.
See Fig. 16.
b. Open outer burner door.
c. Slacken off pinch screw securing flame sensor to
location by bush.
d. Withdraw flame sensor from location bush and detach
cable leads at terminal block. (Clean hole).
e. Refit flame sensor and re-assemble in reverse manner
of dis-assembly, and remake cable terminations.
The flame sensor is now ready for use.
18
Fig.24
Fig.25
Fig.26
DESN 511022
DESN 511323