WE USE WHAT IS CALLED A "LOAD CALCULATION" WHICH IS A PROSCESS THAT DETERMINES THE PROPER SIZE (TONAGE OR BTU) NEEDED FOR YOUR HOME.
BASICALLY WHAT WE DO IS GATHER INFORMATION ABOUT YOUR HOME AND PROCESS THAT INFORMATION VIA COMPUTER SOFTWARE, WHICH THEN GIVES US THE PROPER FIT. THIS SYSTEM OF SIZING IS QUICKLY BECOMING THE STANDARD AND MAY BECOME A REQUIREMENT FROM LOCAL BUILDINGS AND CODES.