SWISCO - The Replacement Hardware Authority

stamp 2900 bsi

A home owner from nc says:
stamp reads 2900 bsi
Profile picture of Donna
Donna from SWISCO responded:
Please remove the window sash and place it on a scale. We need the weight of the window sash in pounds to determine the proper stamp option.

If you are unsure of the balance series you selected please reply with detailed photos for us to research.
A handy person from Ohio says:
I have to replace a balance with the same stamp on it. The part is question that is acutally broke is the plastic piece of the pulley system that hooks to the spring. Could I buy the entire assembly and reuse the old spring and not worry about the weight of the sash. (I am not comfortable with removing the entire sash myself)
Profile picture of Donna
Donna from SWISCO responded:
Do not attempt to replace the spring, it is under great pressure and would be dangerous. You will need to remove the window sash to replace the balances.

Please remove the window sash and place it on a scale. We need the weight of the window sash in pounds to determine the proper stamp option.

If you are unsure of the balance series you selected please reply with detailed photos for us to research.
A handy person from Ohio says:
Will a bathroom scale provide enough accuracy? I will look at the window and see if I can remove the sash without screwing things up.
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Paul Sr. from SWISCO responded:
Yes, a bathroom scale is good enough. A lot of people weigh themselves and then weigh themselves again holding the sash; then simply subtracting their weight from the total weight to get the weight of the sash. Take a look at this discussion about how to remove a window sash.
A quick learner says:
Dear Sir or Madam:

I am looking to replace a channel balance for a window in my home. I am unable to identify the manufacturer of the window. After asking a question in the online forum, Donna suggested that I get the weight of the sash and send pictures of the old balance.

Based on pictures in your online catalog, I need a series 770, 29 inch balance. I don't know if they differ based on sash weight.

The sash weight is between 19 and 20 pounds.

Please advise me on how to order and pay for a replacement.

Description of photos
Bottom Right - Shows the top of balance. The current one got bent up when I removed it
Top Right - Shows the bottom of the balance and the clip style.
Top Left - Shows how long the spring is.
Bottom Left - Shows where the top pulley rests when the cord is fully retracted.

Thank you for all of your help.
Customer photo of their broken channel balance.
Profile picture of Donna
Donna from SWISCO responded:
29" Series 770 Balance for a sash that weighs between 19 and 20 pounds
Choose stamp option 29C, this will carry a window sash weight range of 18 through 23 pounds.

This information is based on 2 balances per sash. Balances are designed assuming friction in the jamb weather-strip will carry a portion of the sash weight. Suggested sash weights are approximate.
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