Casey from SWISCO responded:
May 15, 2014
Hi Brian,
Yes, looking at the 38 4 original stamp, you most likely need the 3840 option. To check, remove the window sash and place it on a scale. A pair of S380-39 balances with stamp 3840 will carry a window sash weight range of 24 through and including 30 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. If you are unsure of the series you selected, please post a few detailed images of the balance fittings with detailed measurements for us to research. |