Is this forum for international dicussion? I am glad to meet you up here and hope that I can learn much from you, the HVAC experts. I am from electrical world but it seems that electrical system and HVAC have a very close connection. My new job is to work for a general construction firm in a wide range of operation including infrastruction, civil, ME... So, having knowledge of an insider of HVAC world would be great for the job. I like HVAC, too.