Appendix; Water Quality Requirements According To Trd 701 - Viessmann VITOPLEX 100?LS Installation And Service Instructions Manual

Appendix

Water quality requirements according to TRD 701

For steam operation it is advisable to feed back as much condensate as
possible to the feed water tank.
Treat the condensate with top−up water, so that the following conditions are
maintained:
Boiler feed water requirements
General requirements
pH value at 25 ºC
El. conductivity at 25 ºC
Total alkaline earths
2+ 2+
(Ca + Mg )
Oxygen (O )
2
Bound carbon dioxide (CO
Free carbon dioxide (CO
Oxidisability (Mn VII ³ Mn II)
as KMnO
4
Oil, grease
Boiler water requirements
General requirements
pH value at 25 ºC
Acid capacity up to pH 8.2 (K
El. conductivity at 25 ºC
Phosphate (PO )
4
The addition of phosphate is recommended, but is not always essential.
Conversion:
= 5.6 ºdH; 1 ºdH = 0.1792 mol/m
3
1 mol/m
26
mS/cm
mmol/litre
mg/litre
) mg/litre
2
) mg/litre
2
mg/litre
mg/litre
) mmol/litre
S8.2
mS/cm
mg/litre
; 1 mval/kg = 2.8 ºdH
3
Colourless, clear and free
from undissolved
substances
Only guide values
applicable to boiler water
Colourless, clear and free
from undissolved
substances
> 9
< 0.015
< 0.1
< 25
n. n.
< 10
< 3
8.5 to 10
1 to 12
< 5000
10 to 20