34000 Autry Street, Livonia, MI 48150 | 800.968.5530 | Fax 734.419.0209 | www.hamiltonengineering.com | LIT91127US REV 5/2018
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ELECTRICAL
PART 2. ELECTRICAL
A. ELECTRICAL CONNECTION / REQUIREMENTS
The electrical connection for the EVO is on the bottom of the unit. There is a 1/2" knockout location for an electrical connection for
the heater’s incoming power connection. All electrical wiring must be performed by a qualified licensed electrician in accordance
with National Electrical Code ANSI/NFPA and/or the Canadian Electrical Code, Part 1 CSA C22.1, or to any applicable local
codes and standards. For your convenience, all the points for electrical connections needed to operate the EVO are labeled.
Note: Always check electrical ground to known earth ground; if less than 0.5 ohms, ground is sufficient (meter MUST
be on lowest setting).
We recommend a simplified test, differing from one looking for building earth ground issues, it is our intent to use this test as
an indicator of equipment room (boiler or water heater) electrical grounding issues, or equipment bonding issues, not prove
the earth ground to the building.
Take an Ohm meter and place one lead on a known earth ground (not the ground wire on the boiler), and place the other
lead on either 1) The near boiler system piping, 2) The boiler heat exchanger, or 3) The boiler cabinet.
If any of those readings exceed 0.5 Ohms, then it is a good indicator that there may be sufficient stray current flowing
through the water in the piping system to accelerate or amplify conditions that can cause pump, boiler or piping issues in
the not too distant future.
If any readings are over 0.5 ohms, an electrician should be brought in to correct the problem.
The electrical requirements are for standard 208–240 volts, 50/60 Hz 15 Amp service. This unit is wired with #18 awg and
internally fused for no more than 3.15 Amps. When the unit is first powered on, there is a self-setting of the electronics for 50
Hz or 60 Hz. At every power up, the electronics will take a couple of seconds to compare the pulses of the power to the pulses
of the crystal, which is built into the electronics. Then all time-related functions are correct no matter the power source.
The standard supplied pumps are all 208–240 VAC, 60 cycle and are to be wired to terminals indicated on the appliance. In
50 cycle applications, other pumps may need to be supplied, depending on water conditions. With the 914 controller there
is an ability to program a custom pump delay time, or to use a continuous (no time out) setting. The factory default is a 1
minute delay to turn off after completing a burn cycle.
B. INTERNAL WIRING CONNECTION
CAUTION
The incoming power shall be connected directly to the labeled, intended
connection points only. Failure to do so may result in an electrical short and
the control board will have to be replaced!
DANGER
IT IS EXTREMELY IMPORTANT THAT THIS UNIT BE PROPERLY GROUNDED!
IT IS VERY IMPORTANT THAT THE BUILDING GROUND IS INSPECTED BY A
QUALIFIED ELECTRICIAN PRIOR TO MAKING THIS CONNECTION!
Failure to confirm proper grounding and the absence of stray voltage may result in premature component failure.
See start up and commissioning documents (LIT91111 - Start Up Checklist) for details.
Terminal 27 in the electrical compartment must be connected to the building ground system.
The incoming 208–240 volt single phase power supply is connected to terminals 26 through 28.
It is important that the electrical power is not turned on at this time. Double check all connections and then turn the
power on. The display that is provided with the EVO should now be reading the Setpoint temperature.
Note: See Start-Up Procedures (Part 6, page 38) to change the temperature setting or run the appliance.