[NiHaoMike]

150F or so is already getting close to the limit for a R410a compressor running on R290. The evaporating temperature can go to maybe 100F, higher if you use a VFD. Counterintuitively, lower evaporating temperatures are more problematic with high condensing temperatures due to higher compression ratios. You might want to add a thermal sensor to the discharge line. 200F is the maximum limit for most applications, with 180F or so being the preferred maximum.

Solid state heat pumps can go all the way to the boiling point and beyond, but they're nowhere as efficient as compressor heat pumps.