Sealed Systems
Page 22
7.1.2 PRESSURE
GAUGE
The pressure gauge must have an operating range of 0 to 4 bar.
It must be located in an accessible place next to the fi lling loop for
the system.
7.1.3 SAFETY
VALVE
The safety valve should be fi tted in the fl ow pipework near to the
boiler.
The pipework between the safety valve and boiler must be
unrestricted, i.e. no valves. The safety valve should be connected
to a discharge pipe which will allow the discharge to be seen, but
cannot cause injury to persons or damage to property.
7.1.4 FILLING
LOOP
Provision should be made to replace water lost from the system.
This can be done manually (where allowed by the local water
7.1
SEALED
SYSTEM
REQUIREMENTS
All Grant Vortex models are suitable for use with sealed systems
complying with the requirements of BS EN 12828, BS EN 12831
and BS EN 14336.
The system must be provided with the following items:
• Diaphragm expansion vessel complying with BS EN 13831
• Pressure
gauge
• Pressure relief (safety) valve
• Approved method for fi lling the system
7.1.1 EXPANSION VESSEL
The expansion vessel should be fi tted in the return pipework as
shown in Figure 7-2. To reduce the operating temperature of the
expansion vessel, position it below the pipe to which it is connected.
The expansion vessel may be positioned away from the system,
providing the connecting pipe is not less than 15 mm diameter. If
the expansion vessel is connected via a fl exible hose, care must be
taken to ensure that the hose is not twisted or kinked.
Figure 7-1:
Sealed system
Figure 7-2:
Sealed system boilers
If thermostatic radiator valves are
fitted, the system
must
incorporate an
adequate by-pass.
7 SEALED SYSTEMS
Ensure that the expansion vessel used is of
suffi cient size for the system volume.
Refer to BS 7074-1 or The Domestic Heating
Design Guide for sizing the required vessel.
NOTE
Figure 7-1:
Sealed System
Figure 7-2:
Sealed System Boilers
