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Installation
Greenstar FS/Combi FS – 6 720 810 590 (2020/04)
34
6.2
Comparing the size of the integrated expansion
vessel (KWB-3A boiler only)
The following diagrams allow verifying that the integrated expansion
vessel has sufficient capacity for the intended application, or if an
additional expansion vessel is needed (not for radiant floor heating).
The following standard conditions were used:
• Pre-charge volume 20% of the rated volume in the expansion vessel
• Differential to the safety valve of 7.25 psi (0.5 bar)
• Pre-charge pressure of the expansion vessel equal to the static
system height above the boiler
• Maximum operating pressure: 30 psi (2.07 bar)
Fig. 16 Operating capacity of the expansion vessel in °F and gallons
Fig. 17 Operating capacity of the expansion vessel in °C and liters
Key to Fig. 16 and Fig. 17:
[l]
Pre-charge pressure 7.25 psi (0.5 bar) (default setting)
[ll]
Pre-charge pressure 10.9 psi (0.75 bar)
[lll]
Pre-charge pressure 14.5 psi (1.0 bar)
[t
V
]
Supply temperature in °F ( °C)
[V
A
] System capacity in gallons (liters)
[A]
Within operating capacity of the expansion vessel (left of the
relevant curve)
[B]
Additional expansion vessel required (right of the relevant curve)
▶ If results are borderline: Determine precise vessel sizes.
▶ If the results are to the right of the curve: Install additional expansion
vessel.
6.3
KBR..-3A appliances (heating boilers): Selecting an
expansion vessel
External expansion vessel
▶ Determine size of the expansion vessel.
Fig. 18 Sample installation - expansion vessel
6.4
Selecting the installation location
Installation location requirements
Follow the current national and local codes and regulations
▶ Follow country specific requirements
▶ Follow installation instructions of the venting system accessories and
their clearances
Combustion air
To avoid corrosion, keep the supply of combustion air free of corrosive
substances; contained in solvents, paints, adhesives, propellants and
domestic cleaning agents.
Table 17 Corrosive materials
200
80
100
120
140
160
180
0
20
40
80
100
120
60
t
V
/°F
V
A
/gal
6720641933-13.1O
A
B
I
III
II
90
30
40
50
60
70
80
0
75
150
300
375
450
225
t
V
/°C
V
A
/l
6720641933-27.1O
A
B
I
III
II
Industrial sources
Chemical cleaning
Trichloroethylene, tetrachloroethylene,
fluorinated hydrocarbons
Degreasing bath
Perchloroethylene, trichloroethylene,
methylchloroform
Printing shops
Trichloroethylene
Hair salons
Aerosol propellants, hydrocarbons containing
fluorine and chlorine
(difluorodichloromethane)
Household sources
Cleaning and
degreasing agents
Perchloroethylene, methylchloroform,
trichloroethylene, methylene chloride, carbon
tetrachloride, hydrochloric acid
Workshop
Solvents and thinners Various chlorinated hydrocarbons
Aerosols
Chlorofluorinated hydrocarbons
(difluorodichloromethane)
6 720 810 590-18.1Wo