23 lbs sash 29" tall. single hung constant force

Question

Spring block is 1-1/4 inch wide and 5/8 inch thick. Window support lug is 3/8" long from edge of window to head and head is 3/8" wide at its widest, approximately 1/8" at its thinnest. 23 lbs sash weighed alone.  29" tall sash

Tom · Accepted Answer

Thanks for contacting us. Your pivot shoe looks like our 15-177, which itself is compatible with our Series 152 coil spring. Look these parts over and let me know what you think. Your cover looks to be in good condition so you can probably still use that.

As for what Series 152 option to use, it depends on how many springs are used to support it. 23 pounds is pretty heavy so I would imagine you use four springs. If so, I recommend our S152-6. It'll be a little stronger, supporting 24 pounds, but I think that will be fine.