Channel balance replacement

Hello! I feel pretty confident that we can help, but I'm unfortunately not sure what you have. We have dozens of different balances with that stamp. It's not a product code or anything, it just indicates the strength of the spring.

In order to figure out what Series this is, I need you to remove an undamaged version of this balance from the window and show me clear pictures of the top and bottom nylon fittings. I will also need to know the dimensions of these fittings.

Thanks for getting back to us. I'm sorry to say that we don't sell any balance with a metal channel length that measures in 3/4" increments. Can you please verify that measurement? These are always made in full inch increments; with your old stamp of "28 3," the metal channel should be 29".

Assuming that it is 29", then I believe you have either our S351-29 or S390-29, depending on the depth of the bottom shoe. That's the only difference between them. I recommend measuring your shoe and referring to our dimensions to confirm the best match.

Comparison of the S351 and S390 balance shoes.

Great, you're welcome to purchase the S390-29 (2830) balances directly on our website as long as your metal channel measures exactly 29" long, not including the end fittings. 

If you need new weatherstripping and clips as well, we may be able to help but we would need to see the end profile of your original seals uninstalled and photos of any other parts that you need to compare to our inventory. 

Your 28 3 stamp indicates the strength of the balance spring needed to support the weight of the sash. The corresponding strength option would be 2830, which will support a sash between 16-23 lbs. as stated in the chart on the S390-29 product page. Take a look and let us know if you have any other questions. 

Thank you for confirming. Unforutnately, we do not carry a version of these balances with a 28-3/4" long metal channel and it is not a size that any of our suppliers are familiar with. In our experience, these types of balance measurements normally indicate that custom modifications were made for your specific window. If so, your best bet would be to reach out to the manufacturer directly.