Ambirad VISION COMPACT VC40, Operation, Maintenance And Servicing Manual

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6
The flexible duct supplied MUST be fitted
between the re-circulation air and the burner
with pipe clamps as provided.
Flue connections - General (All
models)
The Vision Compact heater may be installed
with or without a flue to the atmosphere
providing the air supply and building
ventilation requirements as stated in BS 6896:
1991 are complied with and providing due
consideration is given to the possibilities of
condensation forming on cold surfaces when
used as an unflued heater.
Unflued installation
For unflued heaters (UK Only) a fan baffle
must be attached to the fan outlet. (Part No
201484).
Permanent ventilation required is as follows:
Natural ventilation
(To be fitted at high and low level with
minimum distance between 3m).
Low level, when air change rate is less than
33m
3
/h/kW of total rated input, either: 1.4cm
2
for each 1m
3
/h/kW below 33m
3
/h/kW or
46cm
2
/kW of total rated input.
High level, above areas where personnel are
working is as above.
Mechanical ventilation
Minimum proven air flow is 33m
3
/h/kW of the
total rated heated input.
Model VC40
Gas type Natural Gas (G20) Propane Gas (G31)
Mass flow rate of flue gases (kg/s) 0.0317 0.0176
Flue gas temperature (˚C) @ flue outlet 185 243
Flue pressure (Pa) Positive 120 120
Figure 5 - Natural Gas Only
9 Flue connection
Flue technical details
If the heater is installed without a flue,
ensure that combustion gases do not
impinge on combustible materials. The
maximum permitted temperature for such
materials is 50˚C. EN416.
Flued installation
The Vision Compact heater may be installed
with a fixed flue. A flue kit (supplied as an
optional extra by the manufacturer) must be
fitted to the flue exit, this kit connects from
the flue outlet to a 5” adaptor. The flue
fitting is designed to accept either 5” single
wall or 5” twin wall flue.
Propriety twin wall metal joints should be
sealed with heat resistant caulking and
faced off with fire cement.
The flue pipe should be adequately support-
ed at regular intervals from the building
structure and terminated externally with a
British Gas Tested and Certified terminal.
The maximum flue length is 7m and the
maximum number of bends is two on
individually flued appliances. The flue may
be installed vertically or horizontally, but
must be terminated vertically. All connec-
tions in the flue pipe must be properly
sealed.
Natural ventilation
(Preferably at low level)
Up to and including 60kW: 4.5cm
2
/kW.
Over 60kW: 270cm
2
+ 2.25cm
2
/kW in excess
of 60kW total rated input.
Forced ventilation
Minimum proven air flow is 2.35m
3
/h/kW of
total rated input.
For detailed information please refer to BS:
6896:1991, Installation of Gas Fired
Overhead Radiant Heaters for Industrial and
Commercial heating (2nd and 3rd) family
gases.
For calculation method for flue sizing see
Appendix 1 on page 14.
For Herringbone flued heaters see section
14.
all models)