It is important to check the inhibitor concentration after installation, system
modification and at every service in accordance with the inhibitor
manufacturer. (Test kits are available from inhibitor stockists.)
For information or advice regarding any of the above contact Baxi
Customer Support 0344 871 1545.
5.2.7
Showers
If a shower control is supplied from the appliance it should be of the
thermostatic or pressure balanced type. Thermostatic type shower valves
provide the best comfort and guard against water at too high a
temperature. Existing controls may not be suitable - refer to the shower
valve manufacturer.
5.2.8
Expansion vessel (CH only)
The appliance expansion vessel is pre-charged to 1.0 bar. Therefore, the
minimum cold fill pressure is 1.0 bar. The vessel is suitable for correct
operation for system capacities up to 120 litres. For greater system
capacities an additional expansion vessel must be fitted.
For GB refer to BS 7074 Pt 1. For IE, the current edition of IS 813
Domestic Gas Installations.
Checking the charge pressure of the vessel - to check the charge
accurately ensure the system is cold. It is also necessary to relieve the
pressure by draining the boiler. Using a suitable gauge check the pressure
at the valve on the underside of the vessel. Adjust the pressure as
required and repressurise the system.
5.2.9
Safety pressure relief valve
1
Discharge pipe
2
Pressure relief valve
A
The end of the pipe should terminate facing down and towards the
wall
See
BS 6798 for full details.
The pressure relief valve is set at 3 bar, therefore all pipework, fittings, etc.
should be suitable for pressures in excess of 3 bar and temperature in
excess of 100°C.
The pressure relief discharge pipe should be not less than 15mm
diameter, run continuously downward, and discharge outside the building,
preferably over a drain. It should be routed in such a manner that no
hazard occurs to occupants or causes damage to wiring or electrical
components. If it is anticipated that any part of the pipe may be subject to
freezing it should be suitably insulated. The end of the pipe should
terminate facing down and towards the wall.
The discharge must not be above a window, entrance or other public
access. Consideration must be given to the possibility that boiling water/
steam could discharge from the pipe.
Important
The relief valve must never be used to drain the system.
A remote relief valve kit is available to enable the boiler to be installed in
cellars or similar locations below outside ground level.
A boiler discharge pump is available which will dispose of both condensate
& high temperature water from the relief valve. It has a maximum head of
5 metres.
Fig.12
Discharge pipe
PN-0000604
1
1
2
A
5 Before installation
25
