Abstract: A device for recovering residual heat from exhaust gas includes: a dry economizer which heats to-be-heated water by utilizing sensible heat of the exhaust gas, the dry economizer being provided in a duct extending to a funnel through which the exhaust gas is emitted to atmosphere; and a condensation economizer which heats to-be-heated water by utilizing latent heat of condensation of the exhaust gas, the condensation economizer being provided on a downstream side of the dry economizer. The duct includes an upstream duct in which the dry economizer is provided and a downstream duct connected to the upstream duct and directing the exhaust gas to flow upwardly. The condensation economizer is arranged in the downstream duct so that temperature of the exhaust gas amounts to condensation temperature at a vicinity of an upper part of the condensation economizer.

Abstract: A heat pump system usable as an air-conditioning apparatus, a refrigerant apparatus, or a temperature-conditioning apparatus, having a heat capacity detection mechanism for detecting a signal indicative of a ratio of or a difference between the total heat-emitting capacity of the condenser and the total heat-absorbing capacity of the evaporator, and an energy-supplying mechanism for exerting energy onto the refrigerant, thereby compensating for insufficient total hear-absorbing capacity, especially in the cooling mode when condensation capacity increases due to, for example, a cold or wind environment.