For boiler having high resistance heat exchangers and some condensing boilers,
it is recommended to use a low loss header arrangement. The low loss
header maintains a constant boiler flow, this is important where the
boiler has a very low thermal mass i.e. fabricated heat exchangers or heat
exchanger which have a low water content. The low loss header also over
comes the boiler resistance, thereby allowing a low head pump to be used
for system circulation. It is important to have a low pressure where
thermostatic radiators valves are installed to ensure they operate
quietly. Line drawing showing low loss header.
Multiple Zoned Heating
Two or more Pump Plans can be used together to provide additional zones.
For example two Pump Plans would give four zones, i.e. three heating and
one hot water. All that is required is to link the 'P/L' terminal of the
wiring centres together and to take the boiler 'P/L' terminal to the
wiring centre that serves the hot water circuit.