Selection of Weather data

[needhelpplease]

I am an IES Novice. Please, can someone advise which weather data to use for IES modelling.

I have a site in Peterborough, UK and have an epw. file for Peterborough. Is it recommended that I use this for 'Simulation Weather Data' and then one of the 14 CIBSE accredited sites for Building Regulation Compliance? ie Norwich, Birmingham or Nottingham?

or

Would you just use one of the CIBSE accredited sites for 'Simulation Weather Data' as there is more chance that the information is reliable?

There are many files to choose from could someone explain what the difference is between each one:

FWT
MTN
TMY2
TMY3
TRY
DSY
EPW

[jerry]

Hi, is this for Part L2 compliance?
If so, see EPC convention 10.05. There is a spreadsheet downloadable from the NCM website, which tells you which of the 14 weather files to used, based upon the site's postcode.