4.1 L.P.H.W. system
4.1.1 Water temperature
Maximum water temperature is 110°C (high limit
thermostat).
Highest boiler operation water temperature is 95°C
(control thermostat).
Minimum return water temperature is 20°C at a flowrate
related to a ∆t of 20°C (flow/return temperature).
4.1.2 Water pressure
Boiler sections pressure test at 10 bar.
Maximum pressure test boiler block is 8 bar.
Maximum working pressure is 6 bar.
Minimum working pressure boiler is 0.8 bar.
Optional a water pressure switch set at 0.8 bar can be
supplied with the boiler.
4.1.3 Water flow
The minimum water flow through the boiler is:
Output boiler in kW
= ... m
3
/h
93
This minimum flow must be maintained for 5 minutes after
the burner stops firing to avoid high temperature shut-down
due to residuel heat gain.
Due to the design and manufacture of the boiler no specific
minimum water flow requirement exists other than high-
temperature protection.
5
4. APPLICATION
4.1.4 Water treatment
Water treatment under normal circumstances is not
necessary (see our water quality recommendations).
4.1.5 Noise level
The noise level measured around the boiler depending
on boiler room construction is about 50 dBA.
(Noise level taken at 1 meter from the boiler).
4.2 Chimneys
The average flue gas temperature is so low that the
chimney must be in accordance with the guidelines of
British Gas and BS 6644.
