Multiple u-tube down fired water heater
CA 2093169 C · Owner: Rheem Manufacturing Company · Inventors: Hanning, David M.; Stretch, Gordon W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The top storage tank end wall of a down-fired water heater has a first circumferentially spaced series of circular openings formed therethrough and centered about the tank axis and a second, circumferentially spaced series of circular openings centered about the tank axis and spaced radially outwardly of the first series of openings. Vertically disposed within the tank is a circumferentially spaced series of hollow U-tube immersion heating members each having a first open upper end secured to one of the first series of openings, and a second open upper end secured to one of the second series of openings. Shot-type fuel burners extend downwardly into the second open upper tube ends and are …
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 April 1, 1993 and granted August 11, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 1, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 1, 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.