Replacement channels

Question

I have 2 sizes of channels to replace...30" and 27" (measured as you depict on your site and video). From what I can see, it appears I need series 385 balances, but no clue on the sash weight rating. One of the attached photos shows clear markings of
"29 3 HV CMC 7". The other channel is impossible to photograph but I can see faint markings of "26 2 LV CMC 2(?)".
Can you confirm what I need so I can place an order of two of each size?
Thank you.

User submitted photos of a window balance.

Tom · Accepted Answer

The Series 385 is distinguished by the fact that it has the shoe shown at the bottom of this post. If you have that same size of shoe, then you need Series 385 balances.

The 30" balance (29 3) would be S385-30, whereas S385-27 would correspond to the 27" balance (26 2).

Sometimes a SWISCO 2930 is the proper "weight option" for a 29 3 balance (and 2620 for a 26 2), but sometimes the stamp on the metal is wrong. Weigh the window sash to be sure. 2930 is for sashes between 16 and 23 pounds and 2620 is for sashes between 9 and 13 pounds. If your windows match those weights, you can use the stamps I listed. If they don't match the weights, use the chart in the product description to pick the proper option instead.

Comparison of the S378, S380 and S385 balance shoes.