Ttb Thermostat; Boiler Thermostat; Overheat Thermostat; Burner Assembly - Potterton Osprey CF 125 Installation & Service Instructions Manual

Service & Replacement of Parts - Page 22
Fig. 15
Fig. 16

4.3 TTB Thermostat

•
Gain General Access - See 4.1
1. Disconnect the TTB connector, unscrew the TTB
thermostat from the draft diverter and open the cable
clamp. Unscrew earth connection, see Fig. 16.
2. Re-assemble in reverse order.
Note: This device is a safety feature and as such it should
not be disabled or interfered with. Only Potterton parts
should be used for replacement. If the unit continues to trip
then the flue should be checked for spillage. Always check
the operation of the TTB after every service.

4.4 Boiler Thermostat

•
Gain General Access - See 4.1
1. Open the control panel.
2. Remove spring clip on the outside of the thermostat
pocket and pull it clear of the heat exchanger.
3. Remove the user thermostat control knob.
4. Unscrew the user thermostat, note the wire connections
(each wire is numbered) and remove the wires.
5. Re-assemble in reverse order.

4.5 Overheat Thermostat

•
Gain General Access - See 4.1
1. Disconnect the wires from the thermostat.
2. Unscrew the thermostat from the conducting 'Pocket'.
3. Re-assemble in reverse order.

4.6 Burner Assembly

•
Gain General Access - See 4.1
1. Close the gas cock.
2. Disconnect the gas pipe from the gas valve.
3. Disconnect the wiring to the control panel and the
overheat thermostat.
4. Remove the igniter.
5. Unscrew the burner plate - 2 nuts.
6. Remove the gas valve/burner assembly and lift over the
location peg.
7. Pull the assembly forwards, check the condition of the
burner and thermocouple - replace if necessary.
8. Re-assemble in reverse order.
Injector: Use a 12mm spanner to remove the injector,
use a new sealing washer on re-assembly.