Fig.9
12
Pipe Thermostat
Injector Tee
Pump
INJECTOR TEE
Where the gravity and central heating circuits join
together to return to the stove we recommend the
use of an injector tee connection, situated as close
to the unit as possible. This type of tee encourages
a stable flow of hot water through both circuits and
helps to prevent priority being given to the stronger
flow, which is most commonly the pumped central
heating circuit. This way, there will be no shortage
of hot water to the taps when the heating is on.
Where the appliance is to be interlinked with anoth-
er boiler it will be necessary to use a double feed
indirect cylinder in accordance with BS 1566. (See
Fig 10 for an illustration)
Fig.10
WATER CIRCUIT TEMPERATURE
The return water temperature should be maintained
at not less than 40°C so as to avoid condensation on
the boiler and return piping. Fitting a pipe thermo-
stat to the flow pipe of the gravity circuit and wiring it
into the pump control will ensure rapid circulation of
the hot water.
In some circumstances it may be possible to over-
heat the appliance and the water inside will boil.
This will be evident by the sound of a knocking noise
coming from the appliance and pipes around the
house. If this occurs close off all air controls and
manually start the central heating pump if fitted.
One radiator on the heating circuit should be uncon-
trolled to act as a heat leak in the event that the
appliance overheats and has nowhere to discharge
a build up of hot water should the heating circuit be
satisfied. Be aware that steam and boiling water will
be expended from any open vent from the heating
system probably in the roof space at the expansion
tank.
In the unlikely event that the appliance is not oper-
ating in freezing conditions the water must be
drained from the boiler to prevent frost damage.
