White Rodgers 1127 User Manual

CAUTION

WHITE-RODGERS

Operator: Save these instructions for future use!

FAILURE TO READ AND FOLLOW ALL INSTRUCTIONS CAREFULLY
BEFORE INSTALLING OR OPERATING THIS CONTROL COULD CAUSE
PERSONAL INJURY AND/OR PROPERTY DAMAGE.

This control is designed for use on Hot Water Heating systems.

The highly sensitive Hydraulic-Action element is held snugly in
contact with the pipe or tank to provide quick response to
changes in water temperature.

Type 1127 has single-pole, double-throw switch action, offering
terminals that have open-on-rise switch action as well as close­on-rise switch action. This control may be used as a high limit
control, low limit control, circulator control, or as a combination
low limit and circulator control.

TYPE 1127

HOT WATER CONTROL

Surface Type - S.P.D.T.

INSTALLATION INSTRUCTIONS

DESCRIPTION

THESE CONTROLS MUST BE INSTALLED BY A QUALIFIED
INSTALLER.

Do not exceed the specification ratings.
All wiring must conform to local and national electrical codes and

ordinances.
This control is a precision instrument, and should be handled

carefully. Rough handling or distorting components could cause
the control to malfunction.

This control has been accurately calibrated at the factory. Any
attempt to calibrate this control will void the White-Rodgers
warranty.

If the boiler manufacturer recommends a control location, follow
such recommendations. If none is offered, the following informa­tion gives suggested locations.

On a domestic heating system, surface mounted controls
may be attached to either a horizontal or a vertical riser approxi­mately 18 inches above the boiler.

On a unit heater application, they may be attached to the base
of the coil directly in the air path or on the return line.

PRECAUTIONS

WARNING

Do not use on circuits exceeding specified voltage.
Higher voltage will damage control and could cause
shock or fire hazard.

To prevent electrical shock and/or equipment damage,
disconnect electric power to system at main fuse or
circuit breaker box until installation is complete.

INSTALLATION

Installation Rules:

1. Remove the insulation on the pipe or tank where the control

is to be mounted.

2. All rough spots, scale, rust, or paint should be removed with
a file or similar tool.

3. Mount the control to the pipe by means of the two clamps
provided. They should be pulled up snugly.

4. Replace the insulation, entirely embedding the shield which
is around the sensitive element of the control.

WHITE-RODGERS DIVISION

EMERSON ELECTRIC CO.
9797 REAVIS RD., ST. LOUIS, MO. 63123
[phone], FAX [phone]

9999 HWY. 48, MARKHAM, ONT. L3P 3J3
[phone], FAX [phone]

Printed in U.S.A.

PART NO. 37-1209B

Replaces 37-1209 & 37-9122

9547

INSTALLATION CONT.

Convenient Installation – May be mounted
vertically, horizontally, or on an angle. Will
not affect operation of control.

WIRING

All wiring should be done according to local and national electrical codes.

Pipe Insulation Should Cover Shield
Containing Element.

RED

COMMON

BLUE

OPEN ON RISE
OF TEMPERATURE

WHITE

CLOSE ON RISE
OF TEMPERATURE

This control has a single-pole, double-throw snap action switch.
The top left-hand terminal (red) is the common terminal. The top
right-hand terminal (blue) has open-on-rise switch action. The
bottom centre terminal (white) has close-on-rise switch action.

Diagram for Boiler with Tankless Domestic Coil

HIGH
LIMIT

TRANS.

X

X

Diagram for

24 VAC

GAS VALVE

Gas-Fired System

3-WIRE THERMOSTAT

(USE W-B FOR

2-WIRE THERMOSTAT)

The R-B contacts of the low-limit circulator control maintain
domestic hot water at the desired temperature year-round.

When the thermostat calls for heat, the burner starts. The
circulator also starts if the R-W contacts of the low-limit circulator
control are closed.

If excessive boiler temperature causes the high limit to open, the
circulator continues to run but the burner shuts down until the
high limit recloses.

Refer to the wiring diagram supplied by the boiler or burner
manufacturer, or to the suggested circuits included with the
primary control. The information below shows the terminals to
use for the various applications.

Limit Control: When used as either a high limit control or as a
low limit control, use the open-on-rise terminals (red and blue).

Circulator Control: When used as a circulator control, use the
close-on-rise terminals (red and white).

Combination Low Limit and Circulator Control: For this
application, all 3 terminals are used. The wiring diagram below
shows a typical circuit for a hot water system having a boiler with
tankless domestic coil.

TYPE 668 OIL

BURNER CONTROL

(LINE VOLTAGE)

N

R

B

W

JUMPER

142

3

HOT

LINE

JUMPER

X X

HIGH
LIMIT

IGNITION

TRANS.

BURNER

MOTOR

R

B

W

TYPE 1127
LOW-LIMIT

CIRCULATOR

CONTROL

CIRCULATOR

MOTOR

If low boiler temperature causes the R-W contacts of the low­limit circulator control to open, the burner stays on but the
circulator stops until the R-W contacts reclose.

When the thermostat is satisfied, the circulator stops. The
burner also shuts down if the R-B contacts of the low-limit
circulator control are open.

2