Domestic hot water (DHW) on-demand application: DHW relief valve on outlet of water
heater. An isolation valve is not allowed between the water heater and the relief valve
DHW
DCW
Filter (optional)
Figure 38 Tankless DHW Piping Options
Caution
The field supplied thermostatic mixing valve may be installed on the direct domestic
hot water piping connections at the appliance or at the outlet of a domestic hot water
storage tank if using the domestic hot water function. Failure to install the thermostatic
mixing valve may result in a hazardous situation which can cause serious injury or
death.
Domestic Hot Water Delivery
@ 70°F / 39°C temperature rise
CX150 4.1 GPM
CX199 5.5 GPM
Table 7 Domestic hot water delivery
3.12.2 Domestic hot water piping