BaltGaz NEVALUX-8230, User Manual

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Annex II
Guidance to select an expansion membrane tank
Selecting an expansion membrane tank in case of using water as a heat carrier
In case of connecting the boiler to the heating system with a volume of more than 70 liters, it is necessary to install an additional expansion membrane tank, connecting it to the
return heating line really close to the boiler.
In the tables presented below, you can find water volume necessary for filling the elements of the heating system. The volume of the boiler by itself is 2 liters. This data allows
to make an approximate calculation of the water quantity in the heating system to which the boiler will be connected.
TABLES FOR WATER VOLUME CALCULATION:
Another way to determine water volume in the heating system is to compare values of the water sensor before and
after filling the system with water.
Minimal initial pressure in the expansion tank should not be less than the static pressure at the connection point of
the vessel.
Static pressure is a pressure of the water column between the expansion vessel and the highest point of the heating
system. Measuring this height in meters, we calculate static pressure taking 0, 01 MPa of overpressure for each height
meter. Initial pressure in the expansion tank should be approximately 10% more than calculated static pressure.
Example: Measured height is 8 meters, which corresponds to the value of the static value 0,08 MPа. Initial
pressure in the expansion vessel should be approximately (8х0,01) х 1,1=0,09 MPа. To sum up, calculated pressure is
considered as initial one in the heating system with cold water.
.
Copper pipes
Pipes diameter,
mm
Water quantity,
l/m p.
10х0,8
0,05
12х1,0
0,08
15х 1,0
0,13
18х 1,0
0,20
22х1,2
0,30
28х1,2
0,52
35х1,5
0,80
42х1,2
1,20
Steel pipes
Pipe
diameter, mm
Water quantity,
l/m p.
G3/8 0,13
G1/2 0,21
G3/4 0,38
G1 0,60
G11/4 1,02
G11/2 1,39
G2 2,21
G21/2 3,72
G3 5,13
G4 8,71
Water volume in the radiators
Radiator type Power,Wt Volume, l
Cast-iron: For 1 gill
500/160 130 1,01
ТА-1
150 1,34
Т-1
125 1,18
Steеl: For a radiator
11-400/960 915 2,78
11-600/960 1282 4,15
22-600/960 2225 8,30
11-600/1000 1310 2,97
22-600/1000 2225 5,93
11-600/900 1179 3,10
22-600/900 1984 6,30
11-590/960 1091 3,20
22-590/960 1908 6,50
The power is indicated for the parameters 90/70/20 °С, where:
90 –temperature in the direct heating line;
70 – temperature in the reverse heating line;
20 – temperature in the premise