Woodfire Passiv, Operation And Installation Manual

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Before the system is commissioned it should be checked for leaks and to ensure that it is
functioning correctly.
A water pressure of at least 2 bar and a minimum throughput of 900 l / h must be provided
at the cold water inlet of the overheat safety valve. This supply line must not be capable of
being shut off and it must maintain a constant water pressure.
The installation of the overheat safety valve must be designed in such a way that it is
possible to access it to test that it works. This should be at least yearly and is done by
pressing the red button down to verify that cold water flows through the boiler coil and
outside to waste.
Before connecting the cold water pipe to the stove, the pipe must be flushed to prevent the
introduction of impurities into the opening and closing mechanism of the overheat safety
device.
iii. Load unit or load valve
The stove must be installed with a load unit or
load valve to ensure that the return
temperature is always above 55°. The
circulation pump should be controlled by a flue
thermostat or via the automated stove
controller. This will inhibit the formation of tar
on the boiler and so extend cleaning intervals ,
it will protect the boiler against condensation,
and it will improve the efficiency and
effectiveness of the combustion by getting the
firechamber up to running temperature fast,
and then maintaining that temperature.
iv.Integration into the heating system
The boiler stove should only be integrated into a heating system after the complete system
has been designed by an appropriately qualified and experienced heating engineer.
All the relevant safety standards must be complied with.
The intended heating system can be laid out as an open or closed heating system. In any
case sufficient overheating safeguards must be installed.
If installed on a closed (pressurised) system, a pressure relief valve should be installed in
the water circuit as close as practicable to the appliance and in a position where it would
vent safely, along with the overheat safety valve.
If installed on an open vented system, the feed and expansion tank must be manufactured
to BS 4215, and be designed to withstand the 500-hour boil test without leaking or
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