REMEHA Avanta Plus 24s, Installation And Service Manual

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11
Residual head UPR 15-60
0
100
200
300
400
500
600
0 200 400 600 800 1000 1200
CH-flow [l/h]
R
es
id
u
alh
ea
d[
m
b
ar
]
dT 20
°
C 18kW
Pump 'high'
Pump 'low'
Residual head UPR 15-70
0
100
200
300
400
500
600
700
0 200 400 600 800 1000 1200 1400 1600
CH- flow [l/h]
Residual
h
ead
[mbar]
Pump 'high'
Pump 'low'
dT 20 ° C 28kW
2.3.2 Circulation pumps
The Remeha Avanta Plus 24s and 28c are fitted with the
Grundfos UPR 15-60 and the Avanta Plus 35c and 39c with
the UPR 15-70, two-speed circulation pumps. The control unit
ensures that when the hot-water function is active, the pump
runs at ‘high’. The factory setting of the pump for CH func-
tion is ‘low.’ If necessary, the service installer can adjust this
to ‘high’ by switching parameter
21 (from 0 to 1 ) see par .
2.9.8.
LT.AL.W7H.000.013
LT.AL.W7H.000.014
2.3.3 Additional guidelines for the domestic and CH water
•
The system should be filled with mains cold water (for the
UK this will usually have a pH of between 7 and 8).
•
Power flush the pipes and radiators thoroughly to remove
all fluxes and debris before connecting the boiler to the cen-
tral heating system in accordance with BS 7593 (1992).
m
• The temperature of the central heating pipes and the
radiators can rise to 95°C.
•
Use untreated tap water only to fill the CH system.
•
The pH value of the system water must be between 6 and 9.
•
In case inhibitors are being used, please follow the
instructions given in par. 2.3.4.
2.3.4 Water treatment
If used correctly water treatment can improve the boilers
efficiency and increase the anticipated life expectancy of the
boiler. For further information a special document “Quality
requirements CH water” is available from Broag.
As most systems contain a variety of metals, it is considered
good practice to provide some form of water treatment in order
to prevent or reduce the following:
• Metallic corrosion
•
Formation of scale and sludge
•
Microbiological contamination
•
Chemical changes in the untreated system water
m
All scale deposits however small will reduce the efficiency of
the boiler and should be prevented.
Suitable chemicals and their use should be discussed with a
specialist water treatment company prior to carrying out any
work (environmental aspects, health aspects). The specifica-
tion of the system and manufacturers recommendations must
be taken into account, along with the age and condition of
the system. New systems should be flushed thoroughly to
BS 7593(1992) to remove all traces of flux, debris, grease
and metal swarf generated during installation. Care to be
taken with old systems to ensure any black metallic iron oxide
sludge and other corrosive residues are removed, again by
power flushing, ensuring that the system is drained completely
from all low points.