Junkers SUPRAPUR KBR 120-3 A, Техническое руководство

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Engineering information and sizing the heat source
6 720 645 817 (2010/09)
41
5.4 Condensate drainage
Route the condensate from condensing boilers correctly
into the public sewage system. It is essential to
determine whether the condensate must be neutralised
prior to discharge into the sewer system. This depends
on the boiler output and the relevant regulations of the
local water authority (
Æ
table 20). In Germany, the Code
of Practice ATV-DVWK-A 25 of the Deutsche Vereinigung
für Wasserwirtschaft, Abwasser und Abfall e.V (DWA)
applies for the calculation of the amount of condensate
created per annum. This Code of Practice lists a specific
amount of condensate as an empirical value for natural
gas, i.e. a maximum of 0.14 kg/kWh.
Form. 5 Accurate calculation of the condensate volume
per annum
b
VH
Boiler hours in full use (full load) in h/a
m
K
Specific condensate volume in kg/kWh
(assumed density = 1 kg/l)
Q
F
Rated heat input of the heat source in kW
V
K
Condensate flow rate in l/h
Neutralising obligation
Materials for condensate lines
Suitable materials for condensate lines in accordance
with DWA Code of Practice ATV-DVWK-A 25 [Germany]
are the following:
•
Earthenware pipes (to DIN EN 295-1)
•
Rigid PVC pipes
•
PVC pipes (polyethylene)
•
PE-HD pipes (polypropylene)
•
PP pipes
•
ABS-ASA pipes
•
Stainless steel pipes
•
Borosilicate glass pipes
If admixing of the condensate with domestic waste
water in a ratio of at least 1:25 is assured (
Æ
table 21),
then the following may be used:
•
Fibre cement pipe
•
Cast iron or steel pipes to DIN 19522-1 and
DIN 19530-1 and 19530-2
Copper pipes are unsuitable for draining condensate.
Adequate admixing
Adequate admixing of the condensate with domestic
waste water is given when the conditions in table 21 are
met. The details refer to 2000 hours of full utilisation in
accordance with guideline VDI 2067 (maximum value).
It is advisable to check local regulations on
draining condensate in good time prior to
installation. The local water supply utility is
the responsible body for questions
concerning waste water.
Boiler output in kW Neutralisation
> 25 to ≤ 200 no
1)
1) Neutralisation of the condensate is required for buildings
where the requirement of adequate admixing ( Æ table 21)
with domestic waste water (at a ratio of 1:25) is not met.
> 200 yes
Tab. 20 Neutralising obligation for gas condensing boilers
V
K
Q
F
m
K
×
b
×
VH
=
.
.
Boiler load
Boiler
output
kW
1)
1) Rated heat input
Volume of
condensate
2)
m
3
/a
2) Maximum values at a system temperature 40/30 °C and
2000 hours run
Office and
commercial
buildings
2)
Number of
employees
Residential
building
2)
Number of
residential
units
100 28
≥
40
≥
4
150 42
≥
60
≥
6
200 56 ≥ 80 ≥ 8
Tab. 21 Conditions for adequate admixing of condensate
with domestic waste water