(19)
(11) EP 1 076 212 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
18.12.2002 Bulletin 2002/51

(43) Date of publication A2:
14.02.2001 Bulletin 2001/07

(21) Application number: 00306820.2

(22) Date of filing: 10.08.2000
(51) International Patent Classification (IPC)7: F24H 9/20
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 13.08.1999 US 373863

(71) Applicant: Therm-o-Disc Incorporated
Mansfield, Ohio 44907-0538 (US)

(72) Inventor:
  • Anderson, Jason S.
    Raleigh, North Carolina 27616 (US)

(74) Representative: Price, Nigel John King 
J.A. KEMP & CO. 14 South Square Gray's Inn
London WC1R 5JJ
London WC1R 5JJ (GB)

   


(54) Control and method for electric water heater operation


(57) A control and method for preventing dry start of an electric water heater provides activation of a bottom heating element for a short time and then senses the temperature to detect the absence or presence of water around the bottom heating element. In the absence of water, the control prevents further activation of the heating element. If water is present, the bottom heating element is activated to heat the water to a set point temperature. An additional upper heating element is activatable only after its temperature falls a predetermined amount below the set point temperature. The control may also include a programmable time having the ability to vary the turn off set point temperature in a predetermined manner during different times of a given day and/or week as well as to provide a convenient way to maintain a reduced turn off set point temperature for an extended period of time.






Search report