U.S. Boiler Company PVG3 Installation, Operating And Service Instructions Download

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VI. ELECTRICAL

General.

Install wiring and electrically ground boiler

in accordance with authority having jurisdiction or, in

the absence of such requirements, follow the

National

Electrical Code

, ANSI/NFPA 70, and/or the

Canadian

Electrical Code

Part 1, CSA C22.1, Electrical Code.

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. Install the service switch in the line

voltage “Hot” leg of the power supply. Locate the

service switch such that the boiler can be shut-off

without exposing personnel to danger in the event of

an emergency. Connect the main power supply and

ground to the three (3) boiler wires (black, white and

green) located in the junction box at the inside top of

the boiler jacket.

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 0.6

amp. 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.

For zone valve wiring, a separate 24V transformer

is required rather than attempting to use the boiler

mounted control. Consult zone valve manufacturer for

assistance.

WARNING

The combined boiler and circulator amperage

must not exceed 15 amps.

Install over-current protection in accordance with

authority having jurisdiction or, in the absence of

such requirements, follow the National Electric

Code, NFPA 70, and/or CSA C22.1 Electrical

Code. Do not provide over-current protection

greater than 15 amperes.

Refer to

Figures 17 and 18 for details on the internal

boiler wiring.

DANGER

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.

WARNING

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 over-current device.
Never jump out or make inoperative any safety or operating controls.
The wiring diagrams contained in this manual are for reference purposes only. Each boiler is shipped with

a wiring diagram attached to the front door. Refer to this diagram and the wiring diagram of any controls

used with the boiler. Read, understand and follow all wiring instructions supplied with the controls.

NOTICE

This boiler is equipped with a high water temperature limit rated sensor located inside the internal wiring

of the boiler. This limit provides boiler shutdown in the event the boiler water temperature exceeds the set

point of the limit control. Certain Local Codes require an additional water temperature limit. In addition,

certain types of systems may operate at temperatures below the minimum set point of the limit contained in

the boiler.

If this occurs, install an additional water temperature limit (Honeywell L4006 Aquastat) located in the system

piping as shown in the Water Piping and Trim Section of this manual. Wire as indicated in the Electrical

Section of this manual.