Mark Fohn Livret Technique page 6

stalling in this situation, make sure that no conditions of underpressure can occur. In addition, the
area must be equipped with an adequate number of (permanently open) ventilation openings. If si-
lencers are used, they must be installed at a minimum distance of 800 mm on the output side and
300 mm on the suction side [2].
2.2 Positioning the flue gas exhaust system and air supply
– Curves in the flue gas exhaust ducts and pipes must be avoided to the greatest possible extent
or made as gradual as possible.. Horizontal sections of the flue gas exhaust ducting should be
kept as short as possible and inclined at the maximum possible angle.
– The flue gas exhaust ducts and pipes from two or more air heaters must be kept strictly sepa-
rate and no other connections may be made to them. In order to favour a constant chimney
draught, a draught regulator should be installed. This regulator may not create a constriction of
any kind in the flue gas exhaust duct or pipe. The draught regulator is supplied with the air
heater and must be installed if the length of the flue gas exhaust duct exceeds 3 metres. It is
also possible to install this regulator in a brick-built flue gas chimney (B13 appliance).
– If installation of a chimney draught regulator is not possible or not required, appropriate action
must be taken to ensure an adequate chimney draught. If the chimney draught changes to an
overpressure condition (>0.5 mbar), the burner must be switched off (B23 appliance). The flue
gas exhaust duct must be run in such a way that it cannot cause a fire. A sleeve must be used
when running the duct through walls, floors and the roof boarding.
– The flue gas exhaust duct must be capable of resisting a temperature of 300ºC.The flue gas ex-
haust duct must be hung securely and may not rest on the air heater. In order to allow cleaning
of the appliance, an unobstructed space of approximately 200 mm is required between the flue
gas exhaust duct and the flue gas exit port in the appliance. A resealable connection (clamping
strip) should be used for this. If an appliance is fitted with a chimney draught regulator, flue gas
may briefly blow back into the boiler room or room where it is installed if a downdraught oc-
curs.
– Condensation must not be allowed to enter the heater via the flue gas exhaust. This is why the
flue gas exhaust duct must include a T-piece with a cap.
2.3 Draught regulator [11]
Install the draught regulator in a T-piece in the flue gas duct.
The draught regulator must be set correctly.
Position the draught regulator with the weight at the bottom, see [11]. Adjust the weight so that
the draught regulator remains vertical. NB! Under no circumstances may the draught regulator
be mounted horizontally.
2.4 Gas connection
The installation of the gas pipeline and gas tap must comply with the relevant local and/or national
regulations. The gas tap must be positioned within reach of the appliance. If the connection line is
subject to pressures above 60mbar, this gas tap must be closed. If there is any possibility of the
presence of dirt in the gas, use a gas filter. Always blow through the gas pipe in compliance with
the regulations prior to operating the appliance.
2.5 Electrical connection
Installation must comply with the relevant local and/or national regulations. Ensure that there is a
correct connection group with a mains fuse. PLEASE NOTE: The appliance is phase-sensitive and
will only operate when it has been appropriately earthed. The appliance must be fitted with an iso-
lator switch which interrupts phase and zero (not the earth). The isolator switch must be accessi-
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