Heat source machine

Abstract

To protect a valve box of a first flow rate adjustment valve and a valve box of a second flow rate adjustment valve by absorbing a rise of the inner pressure on the valve box of the first flow rate adjustment valve caused by the expansion of a volume accompanied by a freeze of residual water at a cold time without changing structures of the first flow rate adjustment valve and the second flow rate adjustment valve, in a heat source machine which comprises, in a case, the first flow rate adjustment valve for adjusting a total water passage amount of a water passage amount of a heat exchanger and a water passage amount of a bypass path, and the second flow rate adjustment valve connected to the first flow rate adjustment valve for adjusting a ratio of the water passage amount of the heat exchanger and the water passage amount of the bypass path, the first flow rate adjustment valve being arranged at an inner bottom part of the case and connected to a water supply pipe existing outside the case.SOLUTION: A breaking strain of a resin which forms a valve box 18e of a second flow rate adjustment valve 18 is larger than a breaking strain of a resin which forms a valve box 17d of a first flow rate adjustment valve 17.SELECTED DRAWING: Figure 3

Claims

[Claim 1] A heat source machine including, inside a case, a heat exchanger, a heat source for heating the heat exchanger, a water supply passage and a hot water outlet passage connected to the upstream and downstream sides of the heat exchanger, respectively, a bypass passage branching off from the water supply passage and connected to the hot water outlet passage without passing through the heat exchanger, a first flow rate control valve for adjusting the total water flow rate of the heat exchanger and the bypass passage, and a second flow rate control valve connected to the first flow rate control valve for adjusting the ratio of the water flow rate of the heat exchanger and the bypass passage, The first flow rate control valve is disposed on the inner bottom of the case and connected to a water supply pipe located outside the case, A heat source machine characterized in that the resin forming the valve housing of the second flow control valve is a mixed resin containing an elastomer, and the breaking strain of the resin at temperatures below 0°C is large enough to withstand the increase in internal pressure caused by the freezing of residual water, and is larger than that of a resin not containing elastomer that forms the valve housing of the first flow control valve.

Images