Space Heating System Design - Benchmark mCHP BoilerMate Design, Installation And Servicing Instructions

4.0 HEATING AND HOT WATER
4.2 SPACE HEATING DESIGN
350mm minimum clearance
22mm combined cold feed
and open vent
mCHP BoilerMate
Figure 4.2 Schematic diagram of the open ventred heating system
(a) mCHP BoilerMate A-CLASS models are only available for the open vented heating
systems and schematic arrangement of an open vented system is shown in figures
2.3, 2.4 and 4.2.
(b) Model selection:We recommend that the method for heat loss calculations,radiator
and boiler sizing contained in BS 5449:1990 is used to calculate the design heat
loss of the dwelling.This together with selection data in table 3.3 and the heating
power output of the mCHP unit should be used to determine the suitability of
the proposed system combination for the dwelling.The allowance for hot water is
built in and therefore no additional hot water allowance should be added to the
calculated requirement for space heating.
(c) Design: The installation must comply with the requirements of BS 6798 and BS
5449. To suit conventional radiator based central heating systems, the appliance
will normally provide flow temperature of 82±2
for sizing heating circuit network and radiators should be used.
The pump head available for space heating and mCHP hydraulic circuits is shown in
figures 3.4 and 3.5.The'R'models are fitted with an automatic bypass valve, which
is factory set to operate at a differential pressure of 2.4m head. Its characteristics
are shown in figure 3.3. The appliance connection details are shown in figure 3.2
and table 3.1 in the technical specification section 3.
If the appliance is at the highest point of the system, an automatic air vent is
provided on the appliance. However if any point of the heating system is higher
than the appliance, then an automatic air vent must be fitted at the highest point
in the system.
At least one flushing point should be fitted at the lowest point in the system to
enable the system water to be adequately flushed during commissioning.
(d) Frost protection: If it is necessary,to protect the system installed in unheated spaces
(e.g.garage,outhouse and ventilated roof space),a frost thermostat(s) must be fitted
and wired as shown in sections 5 of this manual.Before fitting the frost protection,
the mCHP manual should also be consulted.
(e) User controls: The mCHP BoilerMate
1-channel programmer and summer winter switch and the room thermostat can
be connected to the appliance (see section 5).
Supplied By www.heating spares.co Tel. 0161 620 6677
Mains cold water
Overflow/Warning pipe
o C. Therefore normal procedures
2000 models are supplied with a factory fitted
h > 250mm
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