Honeywell 3 port valves

[Bunker]

V4044 vs V4073

I found a boxed V4044 on site today (vacant property).
Looking at the spec, these are not a mid position valve so where would you use one?

 

[Roger Welton]

W plan systems, they are used more on the continent i believe so you can have weather comp and dhw controlled form the boiler

 

[Worcester]

Sometimes Solar Thermal, frequently with Heat Pumps

 

[AWheating]

sell it on ebay and buy a mid position to replace it.