I'm working for a company who does a lot central heating jobs, but the problem is that we're always having to measure the rooms, write it down, then go back to the office to get on-line before we can work out the BTUs for a room. What I've been asked to look into and try download (if possible) is a BTU calculator that can just be used on my laptop when I'm out pricing up for jobs and wont require me to have an internet connection to use it. Is there such a thing and if so can someone please let me know where to get it.
Cheers
Cheers