Bosch 520PN Applications Manual page 62

20 | Installation instructions
Fig. 22
[1] Good
[2] Better
[3] Best
Fig. 23
[1] Good
[2] Better
[3] Best
[4] Enclosed vent pipe (Do not install damper)
[5] Unconditioned space (Do not install damper)
[6] Preferred damper position for vertical terminations
6 720 644 887 (2013/02) C 1210 ES/ESC