Series 900 Single Hung Window

A home owner from Sarasota, Fl. says:
I have 3 identical windows in my new home. 2 of which need repaired. they all seem to be in different situations. 1 has no sash guides. The second has a balance of some sort and is inoperable I can't even move or disassemble the sash. The third which seems to be functioning perfectly. I cannot figure out how to remove the sash to identify the parts.

These are NuAir Brand single hung 900 Series. Glass dimensions are 23" high x32" wide. Spec DH-R30 MST 4565 Forced Entry Resistant.

Can you help? I'm pretty handy but don't want to break anything. Below are pictures of my balances. I'll need enough to do two full windows. They are 1/2" wide. Just need to know what the difference is between a 2420 and a 2430.

A customer submitted photo of channel balance attachments.
Profile picture of Paul
Paul from SWISCO responded:
Thanks for posting. The 2420 stamp carries sash weights from 9 to 15 LBS, while the 2430 stamp option carries sash weights from 15 to 19 LBS. 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. I recommend that you take a look at our S385-25 with a 2420 stamp option and see what you think. Please make sure that the dimensions of the attachments match that of your own.

As for the missing top sash guides, could you remove the top sash guides from one of the operating windows and upload a few pictures of them? You say that they are identical, so that would be your best bet. If we see a picture of them, we should be able to help you out.
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