To provide a heat transfer tube for refrigerant, which is a hydrothermal exchanging of a heat pump type water heater using a carbon dioxide as refrigerant, capable of suppressing an increase of a pressure loss and effectively improving a heat transfer performance, and to provide a heat exchanger with the same.
The heat transfer tube 20 is used for the heat exchanger of the heat pump water heater 10 using the carbon dioxide as the refrigerant, and includes: a main tube with an inner circumferential surface 20a; a plurality of fins 200 provided at the inner circumferential surface 20a; and a plurality of grooves between the plurality of fins 200. The plurality of grooves has a first groove 210 with a first width WA and a second groove 212 with a second width WB different from the first width WA.
HOFUKU MAMORU
KITAJIMA HIRONORI
TAKANO MASAO
Kenji Tsunoda
Yuji Iwanaga
Keiko Nakamura
Endo Wako
Takashi Nomiyama
Now Satoshi