What do the different channel balance stamps mean?

Question

We need to know what the option 18c,18b,18c means?  The Balance on your web site looks like the ones we need, we just don't know which option to choose. We don't have any numbers on the balance to refer back to.

Paul · Accepted Answer

Double check your window channel balance thoroughly for a stamp. Sometimes the stamps are very light and worn away. The stamp refers to the strength of the window channel balance. The heavier the window sash is, the stronger the window channel balance needs to be. To weigh your window sash, you must completely remove it from the window frame. After you weigh your window sash, take a look at the chart below to figure out what Series 800 balance stamp you need.

18a: 10 to 20 lbs
18b: 20 to 30 lbs
18c: 30 to 40 lbs

Make sure you choose the appropriate channel window balance strength needed for your window sash. If you were to choose a window channel balance strength that was not strong enough, your window sash will not stay up on its own. If you were to choose a window channel balance strength that was too strong for your window sash, it may raise up on its own.

If you have any questions about the proper channel balance strength you need, please contact SWISCO before you place your order. When you contact SWISCO for help determining the correct window balance strength please include the weight and size of your window sash. Also include if your glass is single pane glass or insulated glass. Click here for the contact form for the Series 800 window sash support channel balance.