broag SEAGOLD 1A HR, Manual

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6
remeha Gas 5a/5a Duo
3. APPLICATION
Output boiler in kW
93
= ... m 3 /h
This minimum flow must be maintained for 5 minutes
after the burner stops firing to avoid high temperature
shut-down due to residual heat gain. Due to the design
and manufacture of the boiler no specific minimum water
flow requirement exists other than for over-temperature
protection.
3.1.4 Water treatment
Water treatment of all systems, but in particular open
vented systems used with the Broag remeha Gas 5a, is
considered necessary good practice in order to:
- avoid metallic corrosion within the system
- avoid sludge and scale information
- reduce to a minimum the risk of microbiological conta-
mination of the system
- minimise chemical action and changes which take
place over a period of time when system water is un-
treated.
The system will contain a variety of metals. Ferrous
metals - cast iron and steel, and non-ferrous metals -
copper, brass and gunmetal, may be present, so it is
essential that treatment is suitable for all of them.
Suitable chamicals and the extent of treatment should be
discussed with specialist manufactures prior to any work
commencing. The specification of new systems and
general condition of older existing systems must be
carefully considered. The removal of debris, flux residue,
grease, metal, swarf etc. from new systems, and any
black magnetic iron exide sludge and other corrosive
residue from old systems is essential.
3.1 L.P.H.W. system
3.1.1 Water temperature
Maximum water temperature is 110
°
C (high limit
thermostat).
Highest operating flow 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).
3.1.2 Water pressure
Boiler sections pressure test at 12 bar.
Maximum pressure test boiler block is 6 bar.
Minimum working pressure boiler is 0.8 bar at a maxi-
mum water temperature of 110
°
C or 0.3 bar at a maxi-
mum water temperature of 95
°
C.
Maximum working pressure boiler is 6 bar.
3.1.3 Water flow
The minimum water flow through the boiler is:
For information on water treatment we advise direct
contact with either:
Fernox Manufacturing Company Ltd.
Britannia Works
Clavering
Essex, CB1L 4QZ
Tel No: 0799 550811
or: Sentinal
Grace Dearborn Ltd
Widnes
Cheshire WA8 8UD
Tel No: 051 495 1861
3.1.5 Noise level
The noise level measured around the boiler depending
on boiler room construction is about 50-55 dBA.
Noise levels taken at 1 meter from the boiler.
3.2 Chimneys
The average flue gas temperature is so low that the
chimney must be made in accordance with the guidelines
of British Gas.