Patterson-Kelley DVSCM-02 owner manual Equivalent Length of Fittings, Sidewall Installations

Thermific® Gas-Fired Boiler Installation

Whichever termination is chosen, it must be double wall vent certified under UL 1738, or ULC-636. When installing a sidewall exhaust system the termination must be backed by a metal plate secured to the wall as shown in the figure.

Correct rain cap,	Typical incorrect
unrestricted.	rain cap.

If the exhaust vent is routed through the roof, the termination must be either the same type as described for a sidewall installation or a rain cap. The preferred method to terminate the exhaust vent is with a rain cap to minimize the drippage of condensate onto the roof and ice build-up.The rain cap should be an

Flue Gas

Outlet

unrestrictive type similar to the figure above. Elbows are also acceptable.

3.4.5 Equivalent Length of Fittings

Fitting Description	Equivalent Length
90º Elbow	10 feet
45º Elbow	5 feet
Rain Cap	10 feet
Boot Tee/135º Tee	10 feet
Standard Tee Used as a	10 feet
Vent Termination

3.4CLEARANCES

In addition to any clearance requirements in Sections

3.1and 3.3 the following clearances must be maintained for inlet and vent components.

3.4.1 Sidewall Installations

Flue Gas

Outlet

Combustion

Air Intake

2' to snow line

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