Harman Stove Company 2 manual Venting, Vent Pipe, Outside Air, Important Notice

Venting	13
Venting

IMPORTANT NOTICE

Pellet Vent Pipe or PL Vent Pipe Must be used.

Fig.22

+ = Positive static pressure = Negative static pressure

Room Sensor

Connection Ports

Outside air flex pipe

goes here

3" PL vent pipe

flue collar

Fig. 23

A combustion blower is used to extract the com- bustion gases from the firebox. This causes a nega- tive pressure in the firebox and a positive pressure in the venting system as shown in fig. 22. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as pos- sible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the diameter should be increased from3" to 4" because a larger pipe causes less flow resistance. Be sure to use approved pellet vent pipe wall and ceiling pass- through fittings to go through combustible walls and ceilings. Be sure to use a starting collar to attach the venting systen to the stove. The starting collar must be sealed to the stove with high temp sili- cone caulking.

Vent Pipe

Pellet venting pipe (also known as PL vent is constructed of two layers with air space between the layers. This air space acts as an insulator and reduces the outside surface temperature to allow a clearance to combustibles of only 3 inches. The sections of pipe lock together to form an air tight seal in most cases; however, in some cases a per- fect seal is not achieved. For this reason and the fact that the Accentra operates with a positive vent pressure, we specify that the joints also be sealed with clear silicone.

Outside Air

Outside air is optional except in mobile homes and where building codes require. The benefit of outside air is mainly noticed in small, very tight houses.

To install outside air use 2 3/8" I.D. flex pipe part number 2-00-08543. There is a break-away hole on the rear panel which must be removed before connecting the flex pipe. The pipe should be run out- side and terminate to the side or below the vent pipe outlet so the flue outlet is more than 12" from the inlet cover. The maximum length run of this pipe is 15 feet. If a longer run is needed, the size must be increased to 3". Inlet cover part number 1-10-08542

InletCover part# 1-10-08542

Flex pipe part# 2-00-08543

Fig. 24

should be used to keep birds, rodents, etc.out of pipe.

HRV

When installing in a house with a Heat Reclaim-

ing Ventilation System (HRV) be sure the system is balanced and is not creating a negative pressure in the house.