Harman Stove Company P61A PL Vent, Must Be Used, Negative Pressure, Shut-down, and Power Failure

Venting

IMPORTANT NOTICE

Approved Pellet Vent Pipe- Widely Known As

"PL Vent", Must Be Used.

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+= Positive Static Pressure - = Negative Static Pressure Fig. 7

Venting

A combustion blower is used to extract the com- bustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. 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 possible 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 interior diameter should be increased from 3" 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. The use of a starting

collar is not always necessary. The first piece of pipe must be secured, with at least 2 fasteners, to the flue collar of the stove. The 2 screws provided are self-drill- ing, however, drilling a 3/32" pilot hole for each screw is recommended due to the material thickness.

Vent Pipe

Pellet venting pipe (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 1 to 3 inches. The sections of pipe lock together to form an air tight seal in most cases. However, in some cases a perfect seal is not achieved. For this reason and the fact that the P61A operates with a positive vent pressure we specify that the joints also be sealed with silicone. Aluminum tape can also be used for any joint that is 1 ft. or more from the outlet of the stove.

We cannot emphasize enough, the importance of sealing every seam and joint in the venting system which is inside the home. Even the smallest pin hole can leak and when it does you will smell wood smoke or a creosote smell in the room. If this occurs check for leaks. Leaks are easiest to see during start-up. Alternatively you can use a smoke pellet to leak test the venting before lighting your first fire.

A CHIMNEY MUST BE OF A TYPE SUITABLE FOR SOLID FUEL.

CHIMNEY AND CONNECTOR MUST BE MAINTAINED IN GOOD CONDITION AND KEPT CLEAN.

Avoiding Smoke and Odors

Negative Pressure, Shut-down, and Power Failure:

To reduce the probability of back-drafting or burn-back in the pellet burning appliance during power failure or shut-down conditions, the stove must be able to draft naturally without exhaust blower operation. Negative pressure in the house will resist this natural draft if not accounted for in the pellet appliance installation.

Heat rises in the house and leaks out at upper levels. This air must be replaced with cold air from outdoors, which flows into lower levels of the house. Vents and chimneys into basements and lower levels of the house can become the conduit for air supply, and reverse under these conditions.

Outside Air:

Harman Home Heating and Hearth & Home Tech- nologies strongly recommend attaching outside air in all installations, especially lower level and main floor locations.

P61A Pellet Stove 9