11/30
3.0 Mechanical/Electrical
Services
3.1 Gas
connection
3.1.1
Connection to a gas service may only be
carried by suitably qualified persons. The
gas installation must comply with the rules in
force using materials appropriate for gas
service installations.
3.1.2 Check
that
the
gas category is in
accordance with the data described on the
air heater.
3.1.3
An adequate gas supply sized to provide the
dynamic pressure for the volume required by
the air heater(s) is essential to maintain the
nominal heat input.
3.1.4
A 90° action gas service tap and, to facilitate
servicing, a disconnect union fitting must be
provided adjacent to the appliance.
3.1.5
Ensure that a gas service includes a filter
and has been tested and purged in
accordance with prescribed practice prior to
commissioning and taking the air heater into
service.
Warning: Never use a flame to test for
gas soundness.
3.2 Electrical
connection
3.2.1
The electrical installation may only be
carried out by suitably qualified persons
observing the rules in force.
3.2.2
Check that the electrical specification is in
accordance with the specified data on the air
heater. A unique appliance wiring diagram
is supplied as a separate document attached
to this one, plus an additional copy attached
to the air heater.
3.2.3
These appliances must be earthed.
3.2.4
A lockable main switch must be installed
adjacent to each appliance and in view when
facing the service compartment. The
isolator must have a contact separation of at
least 3.0mm on all poles.
3.2.5
The cabinet heaters are foreseen with a
control unit supplied by Ambi-Rad.
3.2.6 Ensure when planning the external
appliance control circuitry that power will be
supplied at all times to the air heater, even
when it is control switched in the ‘heat-off’
mode. This is necessary to ensure that the
fan can operate independently of the heating
control. Therefore never incorporate
automatic controls that electrically isolate the
appliance.
Figure 4 :
Legend
c
Control unit
d
Fuse
3.3 Ventilation
requirements
3.3.1
It is essential that sufficient fresh air is
provided for combustion and room
ventilation.
Most traditional building constructions have
a natural air change rate of at least 0.5/h.
Where it is known that the air change rate is
at least 0.5/h and the volume of the heated
space is greater than 4.7m
3
per kW of total
rated heat input, additional ventilation is not
required.
3.3.2
Building volume limits for Ambi-Rad
cabinet heaters based upon 4.7m
3
per kW
of rated heat input for one air heater only
(table 3)
Frame Model
Heat
Input
kW
Room
Volume
m
3
30 36.6 175
I
40 52.2 245
50 62.2 295
60 76.6 360
II
75 91.1 430
90 108.6 510
III
120 145.3 685
140 169.7 800
150 185.3 870
IV
180 215.4 1015
215 262.0 1230
V
250 298.8 1405
If the minimum volumes stated above exist
together with appropriate similar allowances
for other combustion plant that may be
installed in the same space or zone, then
additional ventilation is not required.
