Heat pump design

[furyo]

Greetings,
First time poster, but I´ve been doing a lot of reading in the forum. Congratulations to every participant.

I am currently involved in the process of designing an air to water heat pump for domestic use.

Having determined my power needs I am currently sizing up the compressor. Here is where I need help.
For nominal conditions, 7C air to 35C water, for which temperature should I choose the compressor? I´ve been looking to software like Danfoss´s RS+3 and Copeland Select7. They request evaporator and condensing temperatures superheat and subcooling as well as capacity.
Has we need a delta T to obtain nominal conditions stated before what temps should these be?
Evap. 2
Cond. 40
sc 6
sh 9

Best Regards

[furyo]

Oops,
Forgot to say, working with R410-A.
Regards