SCOTTY SS DB-202A, Руководство пользователя

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SCOTTY SS – INSTRUCTION MANUAL
Scotty SS Nov-05 20
2.8.1 STATIC PRESSURE DROP TEST
(Fig S202-4)
After all connections are made and the ADD-ON installation is complete check the static
pressure in the outlet plenum of the wood furnace. This is done with an inclined
manometer, similar to the Dwyer Model 25, capable of reading 0.2” w.c. to 0.50” of
water column.
Procedure:
1 – Drill hole in wood outlet plenum as indicated, in fig. S202 - 4
2 – Level the inclined manometer, and adjust the zero.
3 - Insert the pressure tube in the hole in the wood outlet plenum.
4 - With all duct work and blower doors in place the static pressure at point “P” in
the wood outlet plenum should measure 0.2” water column (50Pa) with the
blower running.
If the pressure is less than 0.2” w.c. (50 Pa) or that recommended by the electric
furnace manufacturer, it may be corrected by the following means:
1 – Change blower pulley size (usually decrease).
2 – Change blower motor pulley (usually increase).
3 – Increase return air duct (if restricted). If pressure is less than 0.2” w.c. (50Pa)
It may be corrected by increasing the flow area in the return air duct.
4 – If it is a direct drive blower in an oil furnace, you may increase the blower
speed.
PRESSURE CORRECTION – ELECTRIC FURNACE WITH DIRECT DRIVE BLOWER:
If pressure is less than 0.2” w.c. (50Pa) It may be corrected by increasing the
flow area in the return air duct.
Nortron 21B15H – Series B and similar.
CAUTION : Do not change the wiring of the direct drive blower motor.
IMPORTANT – DO NOT CHANGE BLOWER.
CAUTION – Check the blower motor current draw after making any pulley change. If
the blower motor now draws a larger current than that shown on the nameplate a larger
more powerful motor must be installed.