E93.1001EN.C Manual CD
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PIPE CODES WATER HEATER SIDE
Pipe codes for an installation of only one water heater:
-
There’s only one hot- and one cold-water pipe, both encoded D1, and also the main connection
diameter D = D1.
So water heater sided only one pipe diameter is needed. Values in table
A
, § 9.5.1
Pipe codes for cascades of two or more water heaters:
-
First number the water heaters: water heater-1 is the one of which the hot-water-out connection is
found the furthest away from the tank(s).
-
Connections directly to the water heaters D1 = Ø 54
1,5 (mm
mm).
-
Number the horizontal hot water pipes between water heaters: from D1 after water heater-1, up to
D after water heater-last. Number the horizontal cold-water return pipes between water heaters re-
versely: from D1 before water heater-last, to D before water heater-1. Values in tables
B
and
C
,
In this way, for the given type of cascade system (Tichelmann system), pipe diameters will increase
from each water heater in the direction of the tanks, for the hot water as well as the cold-water
connections.
PIPE CODES TANKS’ SIDE
General:
Pipe dimensions at the tanks’ side, for a given cascade, are equal for all tanks, so tanks don’t
need to be numbered.
Pipe codes:
-
Mutual connection pipes between tanks: code D = diameter main connection pipes. Values in table
C
, § 9.5.1.
-
Tank connections: code D
T
= diameter entrance and exit. Values in tank table
D
, § 9.5.2.
REMAINING PIPE CODES
Main connections:
The main connections from cascade to tank(s) get code D = diameter main connection pipes.
Values in table
C
, § 9.5.1.
E
QUIVALENT LENGTH
Equivalent length:
-
Length of the connecting pipes from the water heaters’ cascade to the tank(s) may not exceed a
certain measure. Components, such as bends and the like, contribute to the total length by their
so-called ‘equivalent lengths’.
See table
E
: ‘Equivalent lengths’ in § 9.6 on page 49.
-
To achieve the new maximum length, the equivalent lengths of the applied components must be
deducted from the allowed length without components (first column of the table).
ELABORATED EXAMPLES
At the end of this chapter, in § 9.8, three elaborated examples will be given, demonstrating how to apply the
tables and values given in § 9.5 up to § 9.7 (pump selection).
