Velux TFF 200, Инструкция по применению

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Worked example
The example below is for a G½ temperature relief
valve with a discharge pipe (D2) having 4 No.
elbows and length of 7 m from the tundish to the
point of discharge.
From Tabel 2.3.1
Maximum resistance allowed for a strength length
of 22 mm copper discharge pipe (D2) from a G½
temperature relief valve equates to 9 m.
Substract the resistance for 4 No. 22 mm elbows at
0.8 m each = 3.2 m. Therefore the maximum permit-
ted length equates to 5.8 m.
5.8 m is less than the actual length of 7 m therefore
calculate the next largest size.
Maximum resistance allowed for a straight length of
28 mm pipe (D2) from a G½ temperature relief valve
equates to 18 m.
Substract the resistance for 4 No. 28 mm elbows at
1 m each = 4 m. Therefore the maximum permitted
length equates to 14 m.
As the actual length is 7 m, a 28 mm (D2) copper
pipe will be satisfactory.
2.4 Motorised valves
See instruction supplied with the valve.
NB:
High limit stat to be set at 80-85°C.
High limit stat is set at 80-85°C.
Control stat is set at 70-75°C.
2.5 Dual thermostat
2.5.1 Connection diagram
SECTION I: TANK INSTALLATION SECTION I: TANK INSTALLATION
c
2 1
°c +
c
2
°c +
9 VELUX
c
2 1
°c +
c
2
°c +
Control Limit