A conventional adjustable TXV, for example Alco brand, will allow a maximum superheat setting of around 10.8-11.35K, at evaporator discharge.

I am searching for an adjustable TXV which will allow stable control at superheats higher than this, perhaps as high as up to 14-15K.

The intention is not to use a suction-line heater for this application.

If there are alternative control-valve/sensors that will allow these high superheats to be reached, then I'd be interested as well.