Water Heater Water Heater Brochure

BASIC SIZING GUIDELINES
The flow rate capacity of tankless water heaters depends on
the temperature difference between the desired output and
incoming water temperature. The flow rate comparison chart
and table shown here summarize the flow rate charts found in
the specifications of each model.
Takagi water heaters are sized according to the peak flow
rate requirements, worst-case temperature-rise scenarios,
and types of applications. Once these factors have been
determined, refer to either the flow rate comparison here or
the flow rate charts found in each model’s specifications.Select
the appropriate water heater as well as the amount of water
heaters required.
Match the Unit to Your Needs
Application designers/engineers can decide whether
to size for full flow, expected flow, or utilize probability
models such as the modified “Hunter Curve.” For large
scale applications such as hotels, apartment complexes
and large restaurants, Hunter Curves are commonly used
to estimate the peak flow rate demand when given the
total amount of fixture units within an application. It is up
to the application designer/engineer to determine the
amount of fixture units within any given application.
Condensing Units
Commercial Units
M50
H3M
Cooler Climates
50°F Incoming Groundwater Temperature
Warmer Climates
70°F Incoming Groundwater Temperature
Capacity - Number of Shower Heads (Assuming the set point temperature is 120˚F )
CT-199
110U
Non-Condensing Units
310U/C
510U/C
H3/540P/X3
H3S
H3J
7 Showers
5 Showers
1.5 Showers
4.5 Showers
3 Showers
2.5 Showers
2.5 Showers
1.5 Showers
3.5 Showers
2.5 Showers
3.5 Showers
2.5 Showers
3.5 Showers
2.5 Showers
4 Showers
2.5 Showers
3 Showers
4.5 Showers
6