6- SIZING GUIDE
Please use the chart below to see how many gallons per minute your tankless water heater can produce with
your incoming water temperature. The gallons per minute is calculated assuming 105°F outlet temperature.
Incoming
HA008240
Water
Temperature
40°F
0.8
45°F
0.9
50°F
1.0
55°F
1.1
60°F
1.2
65°F
1.4
70°F
1.6
75°F
1.8
80°F
2.2
To ensure the optimal temperature output and overall performance of your tankless water heater you may
require a flow regulator. These flow regulators are installed on the outlet connection of your tankless water
heater and limit the maximum volume coming out of your unit to a specified flow rate to prevent the exit
temperature from becoming too cool. To learn more about flow regulators or find out how to purchase one for
your tankless water heater visit us online at Eemax.com or contact us at 1-800-543-6163.
Steps for Choosing a Flow Regulator
1. Find your model in the chart on the left
2. Choose the column with the inlet water temperature closest to your geographical location
3. Take the GPM or gallons per minute you find and match it with the corresponding flow regulator on the
right
Inlet Water Temperature
40°F
50°F
HA008240
1.0
1.0
HA011240
1.0
1.0
HA013240
1.0
1.0
HA018240
2.0
2.0
HA024240
2.0
2.0
HA027240
2.0
3.0
HA036240
3.0
4.0
*Selection based on inlet temperature above and outlet temperature of 105°F
HA011240
HA013240
1.2
1.4
1.3
1.5
1.4
1.6
1.5
1.8
1.7
2.0
1.9
2.2
2.2
2.5
2.5
3.0
3.0
3.6
(Gallons per Minute)
FLOW REGULATOR – OPTIONAL
60°F
70°F
Eemax Part Number
1.0
1.5
1.5
2.0
1.5
2.0
2.0
3.0
3.0
4.0
4.0
5.0
5.0
5.0
HA018240
HA024240
1.9
2.5
2.0
2.7
2.2
3.0
2.5
3.3
2.7
3.6
3.1
4.1
3.5
4.7
4.1
5.5
4.9
6.6
Maximum Flow Rate
1.0 GPM
IFR 1-2
1.5 GPM
2.0 GPM
2.0 GPM
3.0 GPM
IFR 3-4
4.0 GPM
5.0 GPM
7
HA027240
HA036240
2.8
3.8
3.1
4.1
3.4
4.5
3.7
4.9
4.1
5.5
4.6
6.1
5.3
7.0
6.1
8.2
7.4
9.8
Connection Size
1/2" Compression
1/2" Compression
1/2" Compression
3/4" NPT
3/4" NPT
3/4" NPT
3/4" NPT