BSI 27C Channel Balance

Question

I need to replace the channel balances on my two non-tilt windows. They are in a condo that was built in about 1984.
The balances are marked "27C B.S.I". The metal channel measures 28" long. The two bent-up channel sides are about 0.632", and the width is about 0.562".
Your Series 390 seems to match; my shoe depth measures 1.11 inch after 38 years of wear.
I do not know what weight range I need. Does the "27C" imply a weight capacity?

Casey · Accepted Answer

Hello,

I agree that as long as your shoe depth measures more than 1", the S390-28 channel balance would be the correct replacement. The 27C stamp on your assembly would generally indicate that you need 2730 strength options for your replacement balances. If you want to be sure, you can weigh your sash to make sure it falls within the 13 to 19-pound weight range that this strength option supports. Thank you!