8
Hoval STU Wood Pellet Boiler
Dimensions and Technical Information
Key:
1
Flow
2
Returns - One either side, both to
be connected to a common inlet header
3
Safety valve connection
4
Drain connections (plugged)
5
Stat & modulating sensor mounting sockets
6
Combustion chamber pressure switch
connection
7
Smoke box condensate drain
8
Delivery auger
9
Damper assembly
10
ID fan
11
FD fan
12
Transfer box with two proximity sensors.
13
Temperature gauge
14
Sight glass assembly
15
Lambda oxygen sensor
16
Smokebox cleaning door
17
Burn back thermostat
18
Burn back water dump device
19
Temp sensor for water dump device
20
Optional Electric ignition gun behind
removable panel
21
Thermal Safety Overload
22
Boiler door microswitch
23
Motorised Burnback Protection Damper
24
EB outlet box
25
Combustion Chamber pressure switch
STU Boiler
150
200
250
300
350
425
500
600
Dimensions:
A
(mm) 2441
2428
2523
2523
3038
3078
3078
3539
B
(mm) 1657
1644
1644
1644
2159
2159
2159
2619
C
(mm)
900
1180
1180
1180
1180
1180
1180
1180
D
(mm) 1740
1940
1940
1940
1940
1940
1940
2210
E
(mm) 1499
1485
1485
1485
2000
2000
2000
2460
F
(mm)
572
755
755
755
755
755
755
730
G
(mm)
680
908
908
908
908
908
908
855
H
(mm)
640
840
840
840
840
840
840
840
J
(mm)
285
285
285
285
285
285
285
285
K
(mm)
240
235
235
235
235
235
235
275
L
(mm) 1008
1116
1116
1116
1516
1516
1516
1516
Connections:
1 Flow
(PN6) DN50
DN80
DN80
DN80
DN80
DN80
DN80 DN100
2 Return
(PN6) 2xDN50 2xDN80 2xDN80 2xDN80 2xDN80 2xDN80 2xDN80 2xDN100
3 Safety valve
(BSP) G1.1/2
ײ
G2
ײ
G2
ײ
G2
ײ
G2
ײ
G2
ײ
G2
ײ
G2
ײ
4 Drain
(BSP) 2xG1.1/2 2xG1.1/2 2xG1.1/2 2xG1.1/2 2xG1.1/2 2xG1.1/2 2xG1.1/2 2xG1.1/2
5 Stat pockets
(BSP) G1/2"
G1/2"
G1/2"
G1/2"
G1/2"
G1/2"
G1/2"
G1/2
ײ
6 Pressure switch (BSP) R3/4"
R3/4"
R3/4"
R3/4"
R3/4"
R3/4"
R3/4
ײ
R3/4
ײ
7 Smoke box drain (mm) G3/4"
G3/4"
G3/4"
G3/4"
G3/4"
G3/4"
G3/4"
G3/4
ײ
8 Delivery auger
(mm)
100
100
100
100
100
125
125
125
9 Damper assembly (mm)
150
150
200
200
200
200
255
255
10 ID inlet fan
(mm)
150
150
200
200
200
200
255
255
Halifax fan No
9
9
12
12
12
12
15
15
ID fan outlet
(mm) 146x127 146x127 172x191 172x191 172x191 172x191 216x241 216x241
A 3ph + N 32A 400V supply is
required for the control panel
operation.
Notes:
•
Thermal safety heat exchanger connections c/w thermostatic control valve connection (3/4") to be connected
to a cold water mains supply. Drain pipework (by others) to be run via tundish to drain.
See Appendix B for further details.
• Boiler mounted control panel not shown but typical sizes are:
Models 150 to 425: 600mm W x 800mm H x 260mm D
Models 500 and 600: 800mm W x 1200mm H x 300mm D
This may change and should be checked on a site by site basis.
An automatic air vent, should be fitted by
the installer at high level on the flow
pipework connecting to the boiler.