Window Balance

Question

Hi,
I think I have the correct part number but I wanted to get input and just make sure.
Attached are pictures of my balance. It's 1/2" wide and 29" long. The window weighs about 23lbs. I believe the part# is Series 385 with the 2840 option. If this is correct I will get these ordered.

Thanks
Dave T

User submitted photos of a window balance.

Tom · Accepted Answer

Hi, Dave. This could be either the S380-29 or S385-29, depending on the size of the shoe. In either case, the stamp option could be either a 2830 or 2840. Your old balance is a 2830. I suggest weighing the sash again, but more accurately. If the sash is less than 23 pounds, even just part of a pound less, go with 2830. If it's more than 23, go with 2840. Or you can always default to the stamp option of your old balance, but that is a less certain method. As for the Series, to verify it, you'll need to measure your bottom plastic shoe, as shown in the picture below. If, as in the photo, it measures 1-3/32", you are correct about the S385-29. If it measures 1", choose an S380-29. Here is a guide to measuring your shoe:

Comparison of the S378, S380 and S385 balance shoes.