Reliance Holmes Heating And Cooling Ottawa

My less than two year old Carrier Infinity Greenspeed (high efficiency (97%) variable speed modulating) furnace shut down unexpectedly early this Sunday morning. Within two hours of my call Furnace Technician Mike Labelle (employee number 4231) arrived and quickly diagnosed the problem as a blocked condensate drain tube. He had to disassemble and dry out the internal exhaust fan blower and "p" trap and clean the external condensate drain tube.
He was extremely efficient and knowledgeable and doublechecked his work before closing up the furnace and testing it to confirm it was back working perfectly. He wisely advised me to pour two cups of vinegar into the external condensate drain tube each month to keep it clean. This crucial preventative maintenance measure was omitted from discussions with the installing contractor (not Reliance/Holmes) and would have been good to know since the tube is long and has a low slope and prone to build up of algae.