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DESIGN
SY
STEM DET
AILS
Heating System
Equipment/Pipe Sizing and Materials
The primary pipework connecting the boiler and the thermal store should be sized
to achieve a maximum of 8°C rise across the boiler or the maximum temperature rise
specified by the boiler manufacturer, whichever is smaller, but in any instance it should
not be less than 22mm copper tube.
The store sensor off control point is 77°C and it is important that the boiler/primary
circuit are capable of providing this temperature at the store sensor.
Note: There should be no valves in the pipework connecting the boiler to the
BoilerMate A-Class OV SOL.
The heating circuit operates on the normal primary boiler temperatures i.e. 82°C flow
and 71°C return. Therefore any traditional hot water radiators or convectors can be
used with this system and no special over-sizing of the heat emitters is necessary.
All the recommendations with regard to pipework systems in this manual are generally
based on the use of BS/EN Standard copper pipework and fittings.
However, we are happy that plastic pipework systems can be used in place of
copper internally as long as the chosen system is recommended for use on domestic
heating systems by the manufacturer and is installed fully in accordance with their
recommendations. We always recommend the use of barrier pipe for these systems.
It is also essential that if an alternative pipework material/system is chosen the
manufacturer confirms that the design criteria of the new system is at least equivalent
to the use of BS/EN Standard copper pipework and fittings or the pipework sizes are
increased accordingly.
It is only necessary to calculate the heating requirements in accordance with BS 5449.
The allowances shown below should be added for domestic hot water. The control
system automatically gives priority to hot water when necessary.
Allowance for domestic hot water
Model
(kw)
BMA 215 OV SOL
3
BMA 225 OV SOL
4
BMA 235 OV SOL
5
BMA 245 OV SOL
6
BMA 265 OV SOL
6
BMA 285 OV SOL
6