10
Maintenance
Greenstar Heatslave II External
ErP
– 6 720 813 722 (2014/09)
4.2
Fault finding
4.3
Maintaining your boiler
Your new boiler represents a long term investment in a reliable,
high quality product.
In order to realise its maximum working life and to ensure it
continues to operate at peak efficiency and performance, it is
essential that servicing and maintenance checks are performed
at least once a year by an OFTEC engineer or other suitably
qualified person.
If you would like to know more about servicing options from
Worcester, Bosch Group, please visit
worcester-bosch.co.uk
.
Please tick the appropriate box on your warranty registration
card for further details of the Worcester, Bosch Group Service
Contract.
When your boiler requires servicing please contact a
Worcester, Bosch Group contact centre (see inside front cover
for details).
In addition to the service contract we are pleased to offer a one-
off annual service or breakdown call out for your boiler.
Maintenance tips
Regularly check the oil level in the tank. Running the tank empty
or low can lead to damage to the burner.
Do not obstruct the flue outlet or the air inlet.
Use in hard water areas
In exceptionally hard water areas a device to prevent scale
formation may be fitted. Installation of a scale inhibitor
assembly should be in accordance with the requirements of the
local water company. An isolating valve should be fitted to
allow for servicing.
4.4
Servicing
You must have the boiler regularly serviced by a competent,
qualified OFTEC registered engineer using approved spares, to
help maintain the economy, safety and reliability of the boiler.
The boiler should be serviced once each year after installation
unless the installation conditions and usage demand more
frequent services.
Problem
Cause
Remedy
Boiler stops working, blue light and
warning triangle flashing and fault
code displayed
Internal error
Press the Reset button and the boiler should
restart, if not call Worcester, Bosch Group,
quoting fault codes
Boiler stops with no fault codes
Possible overheat
Wait 30 minutes for boiler to cool
Boiler stops working, blue light and
warning triangle flashing and fault
codes 9F 855 are displayed
Burner lockout
Press the Reset button to restart the burner.
If the burner fails to fire and fault 9F 855 is
displayed again, check the oil supply to the boiler
Fault codes 9F 856
More than 5 attempts at a reset
during Burner lockout fault 9F 855,
no more reset attempts can be made.
Call Worcester, Bosch Group, quoting fault codes
Desired room temperature is not
reached
Thermostatic radiator valve(s) set
too low
Increase thermostatic radiator valve setting(s)
Room thermostat set too low
Increase room thermostat setting
Temperature control for CH flow on
boiler set too low
Increase CH flow temperature control setting
Air trapped in heating system
Bleed radiators and recharge heating system
Desired room temperature exceeded
by large amount
Radiators are too hot
Turn down thermostatic radiator valves/room
stat
Room temperature rises instead of
falling
Clock is incorrectly set
Check setting
No display or display unit does not
respond
Momentary power failure
Switch off boiler at master switch, wait 30
seconds then switch on again
Hot water temperature too low
Hot water temperature set too low
Check setting
Hot water not in timed period on the
programmer
Check programmer settings
The service engineer must complete the Service
Record in the checklist after each service.
The completed checklist will be required in the
event of any warranty work and may be required
by the local Building Control Inspector.
The checklist and service interval record can be
found at the rear of the Installation,
Commissioning and Servicing Instructions.
