Nortek Reznor 120, Руководство по установке и обслуживанию

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such that the air circulation fan does not interfere with the
operation of the fl ue.
The return air intake and warm air outlet should therefore be
fully ducted to and from the heater, respectively, within the
compartment or plant room.
If the inlet air is ducted to the outside, then the lowest edge of
the inlet air duct must be at least 500mm above the outside
fl oor or ground level, it must also be fi tted with an access
point(s) to allow for cleaning and servicing to occur.
The openings in the structure of the plant room, through
which the ductwork passes must be of fi re resistant material
and constructed to prevent the likelihood of any fi re from
spreading.
In ducted applications the ductwork must be designed so as
to give a static pressure within the limits stated in section 1.15
of this manual. It should be noted that if the static pressure is
too high, nuisance shut-down will occur when the heater goes
out on the overheat limit thermostat, if the static pressure is
too low, then damage can be caused to the fan motor.
Warm air outlets on ducted applications must be such that
they cannot be closed or become blocked, which again would
lead to an increase in static pressure and nuisance shut-down.
The outlets must not be sited so that warm air can be
discharged onto combustible materials, if necessary, guard
rails should be used to ensure that eff ected areas are kept
clear.
Return air intakes must not be located so that potentially
harmful or hazardous contaminated air can be drawn into the
system.
1.13 Flue system.
Warning
It is essential that the products of combustion are fl ued to
the outside of the building. Each heater must have its own
separate fl ue, with a fl ue diameter of not less than is detailed
in section 1.15 within this manual.
The minimum vertical length of fl ue must not be less than
3m. The fl ue should rise vertically, and the number of bends
should be kept to a minimum.
Flue pipes below a height of 2m should be guarded against
the possibility of being accidentally touched when hot by
personnel
Note:
It is strongly advised that BS 5854; 1980, and BS 5440; parts 1
and 2, are used as consultative documents when considering
fl ue requirements.
Care should be taken to ensure that the fl ue terminal is not
situated in a high-pressure area, the proximity of buildings
and other obstacles which will infl uence this must be taken
into account, preferably at the design stage. See pages 15 & 16
Provision must be made for the disconnection of the fl ue for
inspection and service requirements, and it is strongly advised
that where bends are fi tted inspection covers are included.
The materials from which the fl ue is constructed must be
non-combustible, resistant to internal and external corrosion,
and be capable of withstanding the stresses and loadings
associated with normal use.
When designing the fl ue system the prevention of the
formation and entrapment of condensation must be a key
consideration.
Twin wall or insulated systems are recommended, as they tend
to inhibit the formation of condensates.
Where condensation is unavoidable traps should be included
to encourage the condensates to fl ow freely to a point from
which they may be released, preferably into a gully.
The condensate pipe from the fl ue to the disposal point must
be made from corrosion resistant pipe of not less than the
internal diameter of the drain pipe.
If the fl ue passes through a wall, ceiling, or roof made from
combustible material then it has to be sleeved so as to provide
a minimum of a 25mm void between the exterior of the fl ue
and the internal wall of the sleeve. The maximum permitted
temperature of any adjacent combustible material is 65°C.
The position of the fl ue and its terminal should be such that it
does not impair the combustion process.
It should terminate in an exposed position so as to allow the
escape and dissipation of fl ue gases without risk of their
re-entering the property through windows, ventilation ports,
etc. The fl ue should extend to at least 1m above the height of
any object within 3.5m of the terminal.
Flue terminals should be fi tted on all fl ues, the terminal must
be of the approved type, and have outlet grilles on all sides
giving a total free area of at least double that of the fl ue.
Caution
It is imperative that the fl ue should be properly sealed where
it passes through the roof, this can best be achieved by using
the approved method of roof fl ashing plate and cravat.