27
5797 344 - 01
Vitoflex 300-UF Installation & Operating
Mechanical
Safety Devices
(continued)
B
C
D
F
G
H
J
K
L
M
O
P
E
I
A
R
Q
S
T
U
I
I
I
N
P
Pressure relief valve, 30 psi or 60 psi
(UF 1250, 30 psi only)
Q
4 in. or 6 in. Boiler supply flange
3
R
Supply sensor well (sensor supplied)
S
4 in. or 6 in. Boiler return flange
3
T
Return sensor well (sensor supplied)
U
Sensor wells for thermal safety flush valve (R
b
in.)
(sensor
supplied)
1
See section Piping and Installation of Safety Devices
2
Two PRVs must be installed on the UF 1250 - 30 psi boiler. One PRV must be installed and the other PRV
connection must be capped on the UF 1250 - 60 psi boiler. All other models have only one PRV connection.
3
4 in. boiler flange for Vitoflex 300-UF 390-720, 6 in. boiler flange for Vitoflex 300-UF 950-1250
Legend
A
Nipple,
c
in. x 1
b
in.
B
Reducing coupling,
c
in. x
b
in.
C
Boiler water temperature gauge
D
Bushing
c
in. x
a
in.
E
Nipple
a
in. x 2
b
in.
F
Ball valve
a
in.
G
Pressure gauge
H
Sensor well - fixed high limit (sensor supplied)
I
Safety heat exchanger connections, NPTM
b
in.
1
J
PRV Pressure Relief Valve connection cap
2
K
Reducing bushing
L
Nipple
M
Pressure relief valve, 30 psi or 60 psi
N
Reducing bushing (UF 1250, 30 psi only)
O
Nipple (UF 1250, 30 psi only)
Note:
All fittings shown and sensors indicated are
factory supplied. The size and quantity are
matched to the specific boiler model.
The safety equipment for the heating installation must be installed by a heating contractor authorized to do so.