Nortek Reznor VRA-4E Series, Installation, Commissioning, Servicing

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1712VRA ‐ 4EGBEN, pag.. 6/25
Table 4 Min. installation clearances
VRA-4E mm
Top 150
Flue connector 150
Access panel 800
Non access side 150
Bottom 150
Rear* 450
* Measure rear clearance from the back of the motor
Table 5 Recommended mounting heights (m) (*)
VRA-4E 12 20 30
→
-50 60-
→
100 120
→
145
Mounting
height
2,5 3 4 5 6
* He i ght from floor to bottom surface of heater. These are
recommendations only. Positioning of heaters depends on
application.
Air heaters should, where ever possible always be
installed to blow toward or along external wall
surfaces. Where two or more air heaters are
installed in the same room, a general scheme to
ensure continuous air circulation should be
maintained for best results. Suspended heaters are
most effective when located as close to the
occupancy zone as possible, this fact should be
born in mind when determining the mounting heights
to be used. Care should be exercised to avoid
directing warm air directly onto the occupants.
Partitions, columns, counters, storage racking, etc.
should be taken into account when choosing the
location so that an unobstructed path for the air
circulation can be maintained. Where air
heaters are
located in the centre of the space to be heated, the
air should be discharged toward outside walls. In
large areas, they should be located to discharge air
along outside walls with additional heaters provided
to blow air into the centre of the area. In places
where infiltration of cold is excessive, such as
entrance doors it is desirable to locate a heater so
that warm air is discharged directly toward the
source of cold air from a distance of 4,5 - 6,0
metres.
3.3 Combustion air supply & flue system
The air heater may be installed as a balanced flue
(Type C) heater requiring both a combustion air
inlet duct and a flue pipe or as a power vented
(Type B) heater, which requires only a flue pipe
exhausting to outdoors. All products of
combustion must be flued to outdoor atmosphere.
Each heater installed as a type B appliance must
be fitted with an individual flue pipe and the
combustion air inlet opening must be provided
with a protection grill (ask your distributor for the
appropriate protection grill (IP20) (dia130 = PN
02 25094 ). Each heater installed as a type C
appliance must be fitted with an individual
combustion air/flue pipe system. Only systems
specified by the air heater manufacturer may be
used. Common flue and combustion air systems
must not be used!
Figure 2a : Combustion air and flue pipe sockets
1
2
3
4
1 Flue outlet socket
2 Combustion air inlet opening
3 Gas connection inlet with sealing ring
4 Electrical connections
IMPORTANT: The flue must be installed in
accordance with national and local regulations.
Failure to provide proper flueing could result in
death, serious injury and/or property damage.
The air heater must be installed with a flue to the
outside of the building. Safe operation of any
power vented gas apparatus requires a properly
operating flue system, correct provision for
combustion air, and regular maintenance and
inspection.
3.3.1 Flues for power vented installations (Type B
appliances)
If the air heater is to be installed as a type B appliance,
air for combustion will be taken from within the space
where the heater is installed. Ensure that an adequate
air supply for combustion and ventilation is provided
within the building in accordance with the regulations &
rules in force. Table 6 shows flue pipe sizes and
maximum pipe lengths. The minimum flue length is 0.5
metres. Single wall flue pipes are required. All joints
must be sealed to prevent products of combustion from
leaking into the building. An approved flue terminal is
required. If the flue passes through a combustible
element of the building it must be enclosed by a sleeve
of non-combustible material and separated from the
sleeve by at least a 25 mm air break.
The temperature of any combustible material near to
the flue must not exceed 65°C when the heater is in
operation. The flue must be at least 50 mm away
from any combustible material. Single wall flue pipe
exposed to cold air or run through unheated areas
must be insulated. Where condensation is
unavoidable, provision must be made for the
condensation to flow freely to a point to which it can
be released, i.e. a drain or gully. The condensation
drain from the flue must be constructed from non-
corrodible material not less than 20 mm diameter.
Copper or copper based alloys must not be used for
condensation drains.