sizing the balances

Question

I have a vinyl window that is over a sink.  They are about 5-6yo. It's challenging to lift the sash myself, muchness my 73yo mother.  The existing channels look to be in good shape.  The window ways 16.4#   The channels are stamped 1350. Is There an issue using the next channel for a slightly heavier window to help lift it easier?  If so, what would that be?  And, also, your stamps are 1600 series and the existing are 1350 so not sure what to get.

Tom · Accepted Answer

There are issues with going with stronger balances, actually. if the balance is too strong, it will become hard to close, and may even drift up once you close it. It's important to get the balance whose spring strength matches your sash weight; no more, no less. Think of it like Goldilock's porridge. If your old balances are hard to open, it's likely because they are old and the springs are shot. Most channel balances have a lifespan of 5-10 years, but this can be shortened if the windows are opened and closed frequently.