You may be eligible for certification in some provinces and territories if you have more than five years of construction experience and some high school, college or industry courses in plumbing. Be prepared for unexpected problems and help keep your boiler in shape. A gas boiler installation will usually cost £1100 - £1700, depending on which gas boiler you choose. I wrote up a guide to boilers that won’t ignite/have ignitions faults here. Is proud to be a better business bureau accredited.