21
Grant Vortex Oil Boilers
For additional protection of either the entire heating
system, or the boiler and localised pipework, it is
recommended that a frost thermostat be installed.
Refer to Section 9 for connection details.
To protect the heating system, the frost thermostat
should be sited within the house in such a place that it
can detect any rise and fall in the ambient air
temperature, i.e. in a room with a radiator.
Frost protection
4.9
4 - GENERAL BOILER INFORMATION
Fig. 11 - Clearances for Balanced flues
Notes: *
75 mm with protection.
** Only applies if one or both terminals are balanced flues.
Distances measured to rim of terminal.
Clearances recommended by Grant
Engineering (UK) Limited in accordance with
British Standards and Building Regulations.
A
Below a gutter or sanitary pipework
B
Horizontal from an opening, air brick or window
C
Above ground or balcony level
D
Below eaves or balcony
E
From an internal or external corner
F
From a terminal facing the terminal
G
From a surface facing the terminal
H
Vertical from terminals on the same wall
I
Horizontal from terminals on the same wall
J
Below an opening, air brick, window etc.
K
From vertical sanitary pipework
L
Vertical flue from a wall
M From an oil storage tank
Min. distance (mm)
Terminal position
* 600
600
300
*600
300
1200
600
1500
**750
600
300
750
1800
Notes:1 An opening means an openable
element, such as an openable
window, or a permanent opening
such as a permanently open air vent.
2 Notwithstanding the dimensions
given, a terminal should be at least
300 mm from combustible material,
e.g. a window frame.
3 A way of providing protection of
combustible material would be to fit
a heat shield at least 750 mm wide.
Where the frost thermostat is installed outside the house (to
protect a boiler installed in an external boiler room or
garage) or in an attic, it is recommended that it be used in
conjunction with a pipe thermostat to avoid unnecessary and
wasteful overheating of the property. The pipe thermostat
should be located on the boiler return pipe, and set to operate
at 25° C. Refer to Section 9 for connection details.