Any thoughts on converting VAV boxes with elec heat from single or staged heat to SCR control, controlled by a VMA (0-10V)......
The only way you should attempt this is going back to the manufacturer of the heater. If the sell some kind of upgrade kit or are willing to sell you the parts, it should be OK. Anything other than that, and something burns up, your liable for messing with the heater in an unapproved manor.
Try messing with your staging parameters instead. 1/2 the time may get you a better result on a VMA.
If sense were so common everyone would have it !
All opinions expressed are my own. Any advice provided is based on personal experience, generally accepted fact or publicly available information. As such, it is worth exactly what you paid for it, not a penny more not a penny less !!