Hot Air Plenum; Parallel Installation - CADDY PF01302 Installation And Operating Instructions Manual

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NOTE:

It is recommended to install an outside air inlet with a diameter of at least 4" in the room where the heating appliance is

installed (see drawing below). It is preferable to choose a wall which is not exposed to dominant winds, depending on

the conditions surrounding your house.

N.B. The owner of the furnace is responsible for the room's air quality in case of negative pressure or

temporary negative pressure.

If there is a fan in the wood storage room, make sure it does not create a depression in the room where the furnace is

installed.

9.12. HOT AIR PLENUM

Plenums installed on the furnace must be made of metal in accordance with NFPA 90B, 2-1.3.

The hot air plenum coming out of the furnace is to have a minimum height of 24" (610 mm) if the top of the first vertical

section is not flush with the first horizontal section. Otherwise, the minimum height is 18" (457mm). These dimensions

for all hot air furnaces are in accordance with the standards CSA B140.4 et UL 391.

NOTE: TO ENSURE ADEQUATE STATIC PRESSURE, THE SYSTEM SHOULD BE BUILT IN A WAY THAT THE

VOLUME OF COLD AIR RETURN IS AT LEAST EQUAL OR SLIGHTLY HIGHER THAN THE VOLUME OF THE HOT

AIR DISTRIBUTION.

The installation of the Mini-Caddy with another furnace using the same ductwork is not allowed in Canada. This type

of installation is only allowed in the United States. Ideally, the maximum BTU input of the existing oil, gas, or

electric furnace should be equal or higher than the maximum BTU input of the wood furnace. It is mandatory to

respect minimum clearances between the ductwork and combustible material as if the wood furnace was installed as a

standalone unit. The ductwork and furnace should be adjusted in order to reach a static pressure of at least 0.20

IN.WC, but not more than 0.50 IN.WC. A back-flow damper should be installed in the plenum. The back-flow damper

assures that when either unit is operated by itself, the hot air will flow into the home, and not back through the other

furnace. Depending on your installation (see figures examples below), a back-flow damper may be required in each

plenum.

Free air entry

Exterior wall

Insulated pipe (full length)

Fresh air

intake

18"

457mm

MIN.

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