How does the hubbell tankless water heater work, Electrical requirements – Hubbell Electric Heater Company 280-3 27 kW User Manual
Page 4
How Does The Hubbell Tankless Water Heater Work?
Hubbell has applied its 90 years of water heating experience and engineered a tankless electric water heater
that will provide many years of reliable service in your home. The cold water enters the unit and passes
through a flow meter and inlet thermistor which measure the precise flow rate and temperature of the
incoming water. The control system uses advanced logic with solid state switching devices to fully
modulate the power to the heating elements from 0-100% to provide the most accurate and consistent hot
water temperatures in the industry. As the water flows out of the unit a second thermistor makes any
necessary adjustments to ensure the Hubbell Tankless delivers accurate and consistent hot water. With
numerous control features including the ability to track kW hours consumed, operating cost and hot water
usage, the Hubbell Tankless allows the homeowner to maximize their savings and gain the most benefit from
their investment.
Electrical Requirements
Hubbell Tankless Model No.
110-2 145-2 165-2 180-2
280-3
If actual supply voltage is less than 240V, the kW
will be reduced, see de-rating factors below:
If 230 Volt multiply kW by 0.92
If 220 Volt multiply kW by 0.84
If 208 Volt multiply kW by 0.75
To solve for flow rate using a derated kW use the formula:
kW x 6.824 ÷ °FΔT = GPM
°
FΔT = Change in Temperature (Hot - Cold)
Electrical Requirements
kW @ 240V
11
14
16
18
21
24
27
Amps @ 240V
45.8
58.3
66.7
75.0
87.5
100.0
112.5
Min. Recommended Amperage to Home
100
100
125
150
200
200
200
Multiple Circuit Breaker Installation (US Only)
Minimum Double-Pole Circuit
Breaker Size
(quantity x amps)
2 x 25
2 x 35
2 x 40
2 x 40
2 x 50
2 x 60
2 x 60
3 x 40
3 x 40
Min. Feed Wire Size at 75°C
THHN or Equivalent (AWG Copper)
8
8
8
8
8
6
6
8
8
Single Circuit Breaker Installation (Canada & US)
Minimum Double-Pole Circuit
Breaker Size
(quantity x amps)
1 x 50
1 x 70
1 x 80
1 x 80 1 x 100 1 x 110 1 x 125
Min. Feed Wire Size at 75°C
THHN or Equivalent (AWG Copper)
8
6
4
4
3
2
1
PROUDLY MADE IN THE USA
220-3 240-3