U.S. Boiler Company MegaSteam MST288, Installation, Operating And Service Instructions

Page: 34 / 68

34
103536-08 - 4/18
A. GENERAL
1. Install wiring and electrically ground boiler in
accordance with requirements of the authority
having jurisdiction, or in absence of such
requirements the National Electrical Code,
ANSI/NFPA 70.
2. Refer to National Electric Code or Local
Electric Codes for proper size and type of wire
required. Follow Code.
3. A separate electrical circuit must be run from
the main electrical service with an over-current
device/disconnect in the circuit. A service
switch is recommended and may be required
by some local jurisdictions.
4. Use anti-short bushings on all wiring passing
through boiler jacket, junction boxes and/or
control boxes.
5. Use armored cable (BX) over all exposed line
voltage wiring.
6. If an Alliance SL™ indirect water heater is
used, use priority zoning. Do not use priority
zoning for Hydro-Air Systems.
7. Wiring should conform to Figures 20 thru 21.
B. INSTALL A ROOM THERMOSTAT on an
inside wall about four feet above floor. Never
install thermostat on an outside wall or where
it will be influenced by drafts, hot or cold water
pipes, lighting fixtures, television, rays of the sun
or near a fireplace. Keep large furniture away from
thermostat so there will be free movement of room
air around this control.
Heat Anticipator in Thermostat should be set to
match the requirements of the control to which
it is connected. See Figures 21 thru 21B for
desired system and heat anticipator setting. If
system tends to overheat above the thermostat's
temperature setting, reduce heat anticipator
setting by .1 or .2 amps. If system tends to short
cycle without reaching desired room temperature,
increase heat anticipator setting by .1 or .2 amps.
Positively assure all electrical connections are unpowered before attempting installation
or service of electrical components or connections of the boiler or building. Lock out all electrical boxes
with padlock once power is turned off.
DANGER
Failure to properly wire electrical connections to the boiler may result in serious physical
harm.
Electrical power may be from more than one source. Make sure all power is off before attempting any
electrical work.
Each boiler must be protected with a properly sized fused disconnect.
Never jump out or make inoperative any safety or operating controls.
WARNING
The interrupted hot (red) wire must be connected to the L terminal, the neutral (white)
wire must be connected to the N terminal and the constant hot (black) wire must be connected to the
auxiliary terminal or the primary safety control will be damaged.
WARNING
•
•
•
Section VI: Electrical