Can the 26-147 only work on Thermal Guard Windows

We typically only recommend using the 26-147  on Thermal Gard windows, yes. The reason being that it screws into the sash from the bottom; if your sash doesn't have the space to accommodate that, then your window won't be able to close. The lift would just be getting in the way.

If you're just looking for an easy to install generic lift, something like our 26-174 would likely be more suitable. This just screws to the face of the sash, which means it won't get in the way of anything.