HAMWORTHY HEATING LTD
8
WEYMOUTH
500001112/C
7.0 COMMISSIONING
Weymouth Units are supplied factory set and tested to suit the system parameters shown in Figure 2. If the
application falls within these parameters the unit requires minimal commissioning checks.
7.1 Mechanical Installation.
Check that the Weymouth Unit and expansion vessel has been installed correctly, as detailed in section 6.3: Pipe
-work connections. Check also that all lock-shield or lockable valves are correctly set.
7.2 System Flushing.
Ensure that the system has been flushed and all foreign matter has been removed, including pipe scale.
Note!
Should this material come into contact with the expansion vessel diaphragm it could result in premature
failure of the expansion vessel assembly.
7.3 Electrical Installation.
Before working on Weymouth units ensure all electrical circuits connected to it are isolated.
7.4 System Expansion Vessel.
To set or check the expansion vessel charge pressure the lock-shield valve between the Weymouth unit and the
vessel must be closed. The drain cock fitted on the base of the expansion vessel must be open to allow any water
in the vessel to escape.
A suitable gauge should be used to check the charge pressure. Generally a Schrader ‘car type’ valve is fitted
near the top of the expansion vessel. If the charge pressure is too high it can be reduced by depressing the centre
of the Schrader valve or by using a pressure gauge with an integral air release valve. If the charge pressure is too
low a small increase can be provided using a car foot pump other wise an oil free compressor or nitrogen bottle is
recommended.
Note!
The expansion vessel charge pressure should be set to 0.1 bar less than the cold fill pressure.
When the correct pressure is set the Schrader valve protective cap must be replaced.
Check the integrity of the pipe-work. Ensure the lock-shield valve between the Weymouth unit and the expansion
vessel is open and the drain valve is closed. Ensure the air purge plug is fitted (near the top of the expansion
vessel).
