Johnson & Starley 42-451-09, Инструкции по установке, пусконаладке и обслуживанию

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7. VENTILATION & COMBUSTION AIR
37.1 The room or internal space in which the heater is installed requires a permanent air vent of minimum effec-
tive area 62cm
2
(9in
2
). The air vent should be either direct to outside air or to an adjacent room or internal
space (other than a toilet or bathroom) that itself has an equivalent air vent direct to outside.
Note: The above minimum area assumes that an ELJAN 6 circulator is fitted.
7.2 Combustion air may be introduced, via a 127mm (5”) nominal bore pipe, connected to a return air duct
or plenum from a ventilated area and fitted with a lockable damper. The damper should be adjusted to
control combustion airflow to 0.0108m
3
/s (22.9cfm), (i.e. 0.95m/s [165ft/min] velocity in a 127mm [5”] bore
pipe). If this arrangement is used, a non-closeable warm air register MUST be provided in the same area
as the front of the air heater or heater compartment if a return air grille is not located in that area.
7.3 When installed in a compartment, two permanent ventilation openings into the compartment are required,
one at high level and one at low level, both communicating either directly with outside air or with a venti-
lated room or space. The minimum effective areas specified in Table 1 are related to the rated heat input
of the Air Heater, and assuming that and ELJAN 6 circulator is fitted.
7.4 If any room or area from which air is drawn for ventilation or combustion contains an extract fan, the per-
manent vents must be sized to ensure that the operation of the appliance(s) at full rate is/are not adversely
affected. A spillage test as specified in Safety Checks, paragraph 13.8 (is carried out and any remedial work
undertaken.
8. DUCT SYSTEM
(See British Design Manual - Gas fired Warm Air Heating)
8.1 RETURN AIR
8.1.1 Room-sealed appliances may be installed without return air ducting, provided that the path between
the return air grille and the appliance return air inlet is protected in such a manner that the required
air-flow will be maintained at all times. The return air grille MUST have a free area of not less than
1593cm
2
(291in
2
). It is recommended that the return air duct not be routed directly from the main
living area, but from a convenient central area serving the remainder of the dwelling.
8.1.2 The return air system should be constructed of fire-resistant material. The flue shall not be run through
an area serving as a return air plenum. It is extremely important that the correct size of return air
grilles and ducting is used. For heaters on maximum output the return air duct size should not be
less than the equivalent of 300mm x 300mm (12” x 12”). If flexible duct is used the duct diameter
should not be less than 350mm (16”) dia. The return air grille should have a free area of not less
than 1593cm
2
(291in
2
).
8.1.3 An adequate and unobstructed return air path is essential from areas not served by a directly ducted
return and to which warm air is delivered. All such rooms should be fitted with relief grilles which
have a free area of 0.0088m
2
/kW (1in
2
/250Btu/h) of heat supplied to the room. The only exceptions
are kitchens, bathrooms and WCs.
8.1.4 The return air duct should allow for ease of removal for access to the flue.
8.1.5 All duct work in the room or internal space in which the heater is installed shall be mechanically
secured and sealed with ducting tape.
8.2 WARM DELIVERED AIR
8.2.1 All duct work, including riser ducts, should be fully insulated with 50mm (2”) fibreglass or similar.
If short extended duct runs are taken below floor level these should be similarly insulated, and in
addition wrapped with a sound vapour proof barrier, and protected from crushing.
8.2.2 The duct system should be carefully designed (as given in the guidelines in the British System Design
Manual) to suit the needs of its specific heating requirements and building layout. The type of duct
system, (i.e. radial/extended plenum/stepped) should be installed using the least number of fittings
to minimise airflow resistance. The base duct, which equalises the air pressure to supply ducts,
shall be constructed to support the weight of the heater, which shall be secured to the plenum with
screws on at least two sides, and sealed using self-adhesive foam strip, ducting tape or sealing
compound. All ducting and blanking plates shall be mechanically secured and sealed.
TABLE 2. MINIMUM EFFECTIVE AREAS
VENTILATED FROM INSIDE
BUILDING
Low level grille 352cm
2
(54in
2
)
High level grille 176cm
2
(27in
2
)
VENTILATED FROM OUTSIDE
BUILDING
Low level grille 176cm
2
(27in
2
)
High level grille 88cm
2
(13in
2
)