text: Coil balance weight : SWISCO.com
  Coil balance weight.
  A quick learner from Barrie, Ontario says:
  Good Thursday afternoon gentlemen: The S152-7 successfully fixed my small front window. Now I have a second Simonton window in the dining room where the coil balance appears to be broken on the bottom. I am not sure which weight series I should order this time. Each of the two windows involved are 23.5 inches wide by 32 inches high. Can you advise me so I can order the parts needed i.e. shoe and balance. Many thanks from a Canadian customer.
  Great, glad the balances you ordered worked! Is the balance system for this second window the same as before? If so, tell me how many springs are used on each side of the window and the weight of the sash. I can use that information to determine the best replacement option.
  A quick learner from Barrie, ON, Canada says:
  Yes, the balance system appears to be the same, one spring on each side of the side sliding windows.
  The previous windows were 20 x 31 inches and needed a 7 lb series 152 coil balance. I am unable to remove the window to weigh it but it is slightly larger at 23.5 x 32 inches. Will the 7 lb series work for this window as well?
  Knowing the exact sash weight would be ideal, but based on your sash size it may be about 16 pounds. I would highly recommend weighing it just to be sure. If it is about 16 pounds, then I recommend our S152-8.