A quick learner from Forest Grove Oregon says:
November 23, 2009
I am looking to purchase replacement counter balances for a Vinyl Window. The ends look like Series 380 Channel. I measure the length and it is 20 inches. I do not know the Option to select when ordering. There is no stamped number in the Balance. However there is a label on the side "19 4 IT CMC 4". Please let me know which one to order. thanks, Darren
Donna from SWISCO responded:
November 25, 2009
Please remove the window sash and place it on a scale. The weight of the window sash in pounds is needed to determine the proper stamp option.
1910 will carry a window sash weight range of 5 through 8 pounds.
1920 will carry a window sash weight range of 8 through 12 pounds.
1930 will carry a window sash weight range of 12 through 14 pounds.
1940 will carry a window sash weight range of 14 through 17 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.