Set-up
11
Minimum Clearances to Combustibles
For typical installations, Viessmann recommends installing the boiler with
clearances as published on page 10 under Recommended Minimum Clearances for
Service.
Standard installation
(top view)
Boiler Model
VB2 -18 -22 -33 -40 -50 -63
Rear inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
Sides inches
mm
0
0
0
0
0
0
0
0
0
0
0
0
Flue (oil) inches
mm
9
230
9
230
9
230
9
230
9
230
9
230
(gas) inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
Alcove installation
(side view)
Boiler Model
VB2 -18 -22 -33 -40 -50 -63
Rear inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
Sides inches
mm
0
0
0
0
0
0
0
0
0
0
0
0
Flue (oil) inches
mm
9
230
9
230
9
230
9
230
9
230
9
230
(gas) inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
Top inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
Front
(AL)
inches
mm
6
150
6
150
6
150
6
150
6
150
6
150
*
Viessmann strongly recommends maintaining 48” / 1200 mm front clearance on all models.
5167 404 v1.9
min. 6”
150 mm
min. 0” / 0 mm
service
clearance
48”
1220 mm*
min. 6” / 150 mm
service
clearance
48”
1220 mm*
gas:
min. 6” / 150 mm
oil:
min. 9” / 230 mm
min. 6” / 150 mm