Burnham V9A Series Installation, Operating And Service Instructions page 13

A
RAIN CAP
RIGHT
D
WRONG
-
VENT SIZING Area must be the same as or greater than the boiler breeching (Smoke Outlet). A barometric damper may be required on
installations with a high draft condition.
1. If improper vent is suspected, remove pipe at breeching and operate boiler. This will determine if excessive down draft,
blocked or restricted flue, etc. is causing the problem.
2. If using type shown in A above, be sure cap is raised sufficiently above main pipe to allow flue gases to vent unimpeded.
3. A popular type cap is shown in B.
4. The tee is frequently used as shown in C.
5. D and E should not be used due to possible fluctuations in back pressure.
Typical Vents that are used on Forced Draft Boilers, on Low Silhouette Buildings
B
"A" CAP
RIGHT
FAULTY BOILER BURNER OPERATION
Figure 3b: Vents — Faults & Suggestions
C
TEE TYPE
RIGHT
E
WRONG
90°
ELBOW
UP or DOWN
13