Thermal Store with DHW Coil

[John.g]

Do thermal stores have the DHW coil mounted high up in the cylinder, nearly right at the top?.
If so, and assuming a 300 litre store at 75C and if you draw off 100 litres of HW at 40C from cold at 6C do the whole contents of the store then fall, to 64C?. (63.8)

 

[SJB060685]

My understanding is yes the coil is mounted like that. The manufacturer will usually state what draw off and temperature you can get at a certain storage temperature. Although your heat balance equation will give you an idea.