Casey from SWISCO responded:
November 17, 2010
Hi James,
You have a good start with the Series 380 identified and the balance lengths. Next, remove each sash (the ones you are replacing the balances) and place each sash on a scale one at a time. The weight of the window sash in pounds is needed to determine the proper stamp option. The following are the weight ranges for each available option for the 28" and 34" Series 380 balances. S380-28 2710 will carry a window sash weight range of 5 through 9 pounds 2720 will carry 9 through 13 pounds 2730 will carry 13 through 19 pounds 2740 will carry 19 through 26 pounds S380-34 3310 will carry a window sash weight range of 8 through 13 pounds 3320 will carry 13 through 18 pounds 3330 will carry 18 through 23 pounds 3340 will carry 23 through 28 pounds 3350 will carry 28 through 32 pounds This information is based on 2 balances per sash. Balances are designed assuming friction in the jamb weather-strip will carry a portion of the sash weight. Suggested sash weights are approximate. |