Domestic Water System - Morco 24CPM User Instructions And Installation Manual

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A sealed system must only be filled by a competent person using an approved filling
loop connected between the mains water supply pipe and the central heating return
pipe. Once filled the loop should be disconnected and left adjacent to the boiler.
Antifreeze/Inhibitor
The sealed CH circuit should, at all times be filled with the correct concentration of a
suitable antifreeze/inhibitor. Marco recommend Fernox Alphi 11 at a concentration
of at least 25%. This will provide protection on the CH CIRCUIT ONLY down to -11
deg Celsius and sufficient protection from corrosion.
Expansion Vessel
The following table gives the maximum system volume that the integral 7 litre
expansion vessel can sustain.
Vessel charge/initial system pressure (bar) 0.5 1 1.5
Total water content of CH system (litres)
83
64
44
If the total water content exceeds that shown, an additional expansion vessel must
be fitted and connected to the heating system primary return pipe as close as
possible to the appliance. If an extra vessel is required, ensure that the total
capacity of both vessels is adequate. If the pressure display on the boiler control
panel indicates 2.2 bar or greater when the appliance is at maximum temperature
with all radiators in circulation an extra expansion vessel is required.
Pressure Relief Valve
A pressure relief valve set 3 bar (43.5psi) is fitted and a discharge pipe is routed to the
outside of the appliance. This discharge pipe should be extended to terminate safely
away from the appliance to a point where a discharge would not cause damage to
persons or property but would be detected. The pipe should be able to withstand
boiling water, be a minimum of 15mm in diameter, and not include any upward pipe
runs or horizontal runs prone to freezing.
4.7 DOMESTIC WATER SYSTEM
Check that mains supply pressure is within the prescribed range of 0.2 - 1 Obar. If it
exceeds this limit, a pressure reducing valve should be fitted to the mains supply
before the inlet connection.
The final 1 000 mm of the mains supply pipe to the boiler and the hot water outlet
must be in 15mm copper.