High Limit Thermostat; Temperature Control - Worcester 50/70 User Instructions & Customer Care Manual

TEMP
Fig. 2.
Low
Setting
The control knob has a range of adjustment as
indicated by the symbols.
6

TEMPERATURE CONTROL

The temperature control knob gives you control
over the water temperature in your central heating
radiators, and you can adjust it to any position
within the indicated range (as shown in Fig. 2.).
Higher settings obviously mean hotter
radiators and rooms will reach the required
temperature quicker. The ideal setting varies from
property to property, and can only be established
by trial and error and experience: a setting of
medium to high should serve as a good initial
guide.
PLEASE NOTE: The control knob must not be
High
Setting
set below the first indicating bar.
HIGH-LIMIT THERMOSTAT
Your boiler is fitted with two high limit thermostats to protect
the appliance in the event of a control or system malfunction. The
first overheat thermostat is designed to cut out at a lower temperature
than the manual reset overheat thermostat, and will reset itself when
the boiler cools to a safe operating level.
The manual reset thermostat will operate if the boiler reaches a
dangerous temperature. This will have to be reset by pressing the
button located underneath the control box. (See fig 1.)
If the overheat thermostat persistently cuts out then your boiler
requires attention and you should call either your installer or a service
engineer.
LOCKOUT
A flame failure device is incorporated into the control system
of your boiler. So, should the flame fail for any reason, or should
ignition fail to initiate a satisfactory start, the boiler is automatically
locked out for safety. This lockout condition is indicated by a
signal lamp located on the burner control box.
To cancel the burner lockout condition, remove the boiler
front cover and allow two minutes before pressing the illuminated
lockout reset button, which is mounted on the burner control box.