Wet-base, down-fired water heater
CA 2087399 C · Owner: Stretch, Gordon W. · Inventors: Haag, Wilbur L. Jr.; Stretch, Gordon W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A fuel-fired, forced draft water heater is provided with a specially designed burner structure and combustion product flow path that permit the heater to operate with improved fuel efficiency, lowered CO and NOx emissions and an improved water, heat input distribution along the vertical length of the heater. The water heater includes a vertically oriented tank with a vent plenum structure formed at the top end of the tank interior and having an outlet passage connectable to an external combustion product vent pipe. A submerged vertical burner tube extends downwardly from the vent plenum and has an open lower end extending into a submerged turn bowl disposed at the bottom end of the tank …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 15, 1993 and granted February 17, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 15, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 15, 2015.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.