We have wooden spring-loaded double-hung windows that will stay neither open
nor closed. Unless they're locked, the top sash will fall and the bottom
sash will jump to near the center of the frame.

What is it that causes this? I understand older windows with sash weights
and how to repair them, but I don't know how spring-loaded windows are
balanced and why they would do this. I mean, if the spring weren't strong
enough I would expect them to fall, and if the spring were too strong I
would expect them to not stay closed, but what would cause the sashes to go
to the center like this?

We rent, but this is not a priority for our landlord (who lives on the
opposite coast). I am capable of doing most home repair myself and have been
able to deduct the cost, when reasonable, from my rent in the past, but
again the landlord will not see this as a necessary repair and won't want to
pay too much. Bottom line: I'm looking for a cheap fix.

Thanks!

--
-J.

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