Harry Taylor HT2000, Installation & Servicing Manual

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wiring could be impaired as a result of such
contact.
All cabinet heaters must be earthed .
Caution
The main electrical supply must not be
switched off or disconnected as a method
for stopping the heater, the exception to this
is in an emergency, or during servicing,
when the heat exchanger has been allowed
to cool sufficiently to prevent any damage
from occurring. Claims for damage will not
be considered if they have resulted from
incorrect wiring or the incorrect use of the
heater.
2.9 Air Supply
Provision must be made for the existence of
an air supply in order to satisfy both
combustion and ventilation criteria.
It is a requirement that the area where the
air heater is located must have a permanent
air vent of negligible resistance direct to the
outside air.
Such air vents must be positioned so as not
to become blocked or flooded, nor should
they be placed so as to introduce
undesirable matter (e.g. flammable, volatile,
or aggressive chemicals/compounds or
potentially hazardous or harmful
substances) either direct from the outside, or
through their proximity to an adjacent
extraction system.
Note
It is strongly recommended that BS 6230 :
1991 is referred to for further information
concerning ventilation requirements.
Where mechanical ventilation is used it is a
requirement that the inlet is of the
mechanical type, and the outlet is either
mechanical or natural.
2.9.1 Heaters installed within the
heated space.
Where heaters are installed within the space
to be heated (i.e. not a plant room or
enclosure) then:
Combustion air or heater related ventilation
air
will not be required if -
•
The design air change rate of the
heated space is 0.5 air changes per
hour or greater
or
•
The design air change rate may be
satisfied by natural infiltration or by
mechanical ventilation
Combustion and General ventilation
will be
required if -
•
The design air change rate of the
heated space is less than 0.5 air
changes per hour
or
•
Where the heated space has an air
change rate of less than 0.5 air
changes per hour then it will be
necessary to provide
either natural
ventilation openings to the heated
space (section 2.9.1.1 refers)
or the
mechanical ventilation of the heated
space (section 2.9.1.2. refers)
2.9.1.1 Natural Ventilation Openings
to the Heated Space.
If the heated space design air change rate is
less than 0.5 air changes per hour then
provision for low level natural ventilation
openings will only be necessary.
The minimum free area of the low level
natural ventilation opening shall be:
•
2cm
2
for each kW of rated heat input
The low level natural ventilation opening
should be situated on an external wall and
be within 1000 mm of floor level for natural
gas and ideally at floor level for l.p.g gas
installations but in any event no higher than
250 mm.
The table in the next column provides
specific data for each heater model as -