Casey from SWISCO responded:
March 6, 2017
Hi, The 28D is typically replaced with 2840. To check remove the sash and place it on a scale. *Stamp option 2840 will carry a window sash weight range of 23 to 28 lbs.
*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. |