i need to find out my modal?

i've had a survey of my heating system, but before we can go ahead and change it i need to find the modal of my boiler. i don't like touching anything gas related and the survery wasn't aloud to touch it. it's a very old system boiler wich just says "ideal w" nothing else anywhere. has anybody got any idea where i can find this. i've been on the ideal heating site, loads of manual sites that either want money or to install a tool bar first. an help would be extremely recived.