Watts 1156F, T156B, N256 Installation Instructions

Series 1156F, T156B and N256

Feed Water Pressure Regulators

Sizes: 1⁄2" – 3⁄4" (15 – 20mm)

Installation Instructions

1. The Watts Feed Water Pressure
Regulator must be installed on the
cold water supply line to the boiler. It
may be installed in either vertical or
horizontal position. Allow suffi cient
clearance to operate the fast fi ll and
purge lever.

2. Install a shutoff valve upstream
of the regulator.

Note: Local codes typically require the

use of a backfl ow preventer in the
system (Watts Model 9D). Consult
local authorities for the type, instal­lation and testing requirements.
The backfl ow preventer must be
installed upstream of the regulator.

3. Prior to installing the regulator, fl ush
out the supply pipe to clear it of chips,
scale, dirt, etc.

4. Install the Watts regulator in the sup­ply line to the boiler with the arrow on
the valve body pointing in the direction
of fl ow to the boiler.

Expansion

Tank

To Radiation

*See reverse side for servicing and important information.

Installation Diagram

*Pressure

Relief

To

Valve

Hot Water

Boiler

Cold Water

Drain

*Pressure

Relief
Valve

Return

IS-1156F

No. 90
Back ow
Preventer

Shut off

Valve

Operation

1. To fi ll the system, open the shutoff valve upstream of the regulator. This valve must always be kept open when the system is in
operation. Water will fl ow into the system until it is full and under pressure.

Note: Series with Fast Fill and Purge Lever
lever” which permits rapid fi lling of the system, and sustained fl ow for air purging. When the lever is raised to
the vertical position it pushes a removable “Push Rod” down. This manually forces the valve to a wide open
position for maximum fl ow. Returning the lever to its normal position releases the tension on the rod permit­ting the valve to maintain normal system pressure.

Caution: Always observe the Boiler Pressure Gauge when using this feature. Using this feature with the
Purge Valve closed can result in over pressurizing the system or exceeding the Pressure Safety Relief Valve
setting. Over pressurization can result in a water discharge from the Relief Valve. This feature can be disabled
to prevent tampering or accidental misuse of the fast fi ll feature by simply unscrewing the fast fi ll lever cap and
removing the push rod.

2. The regulator is set to deliver water to the boiler at approximately 15 lbs. pressure. This pressure is suffi cient for a 3 story building.
To reset the reducing valve for higher pressure (when the pressure is not suffi cient to lift the water to highest radiation):

A. Calculate the number of feet from the regulator to the top of highest radiation.
B. Multiply this number by 0.43 and add 3 lbs. This will give the pressure required to raise the water to the highest radiator

and keep the system under pressure.

3. To reset the regulator valve:
Remove the fast fi ll lever cap, and loosen the lock nut. To raise the reduced pressure - slowly turn the adjusting screw clockwise
until the system gauge indicates the pressure required. To lower the reduced pressure - turn the adjusting screw counterclockwise.
After completing adjustments, tighten the lock nut and replace the fast fi ll lever cap.

Note: Watts is not responsible for boiler failure on boilers without low water cutoffs.

IMPORTANT: Annual inspection of all water system safety and control valves is required and necessary. Regular inspection, testing

and cleaning assures maximum life and proper product function.

1

⁄2" valves are equipped with a unique and simple “fast fi ll and purge

Service

The strainer screen should be serviced at least twice
a year.

This series is a new development for standard capacity domes­tic water regulation service. It has special unitized construction
which consists of the seat, disc and stem assembly, and strainer
screen all together in one unit for complete replacement
maintenance.

To clean or replace parts:

1. Close the shutoff valve upstream of the regulator.

2. Bleed pressure from system.

3. Loosen and remove the fast fi ll cap. Remove the spring
cage and all parts above the diaphragm.

4. Loosen and remove the diaphragm lock nut and lock washer,
pressure plate and diaphragm from the valve stem.

5. Unscrew seat cylinder from body and remove
entire assembly.

6. Prior to reassembly fl ush valve to remove sediment.

7. After repairs are completed reassemble in reverse order.

Diaphragm

Fast Fill
Lever and
Cap Assembly

Seat and Disc
Assembly

Stem

Seat Cylinder

Troubleshooting

A dripping Pressure Safety Relief Valve can be an indication that
the Feed Water Pressure Regulator requires service.

Important: The pressure Safety Relief Valve is on the system to
protect against excessive water pressure only. The function of the
valve is to release any excess pressure from the system caused
by thermal expansion of the water. Therefore, do not be alarmed
at water drippage as the valve is doing what it is designed to do.
This drippage will not prevent the natural buildup of temperature
in the boiler because the valve operates on pressure only. The
valve will open when the gauge pressure reaches 30 lbs.

To avoid water damage or scalding due to valve operation, a
drain pipe must be connected to the Pressure Safety Relief Valve
and run to a safe place of disposal.

Never plug the discharge of a pressure safety relief valve!

Other possible causes should also be examined prior to servicing
the regulator. Some other possible causes are a water logged air
cushion tank, an over pressurized diaphragm style air cushion
tank, an undersized air cushion tank and, on systems with a
domestic water coil, a leak in the tankless coil.

Periodic inspection of the system by a qualifi ed plumbing and
heating technician is recommended. Corrosive water conditions,
extremely high water temperatures, unauthorized adjustments or
repair could render the valve ineffective for the service intended.
Regular inspection and cleaning of all water safety and control
valves assures maximum life and proper product and system
function.

Strainer
Screen

Disc

Integral
Stainless Steel
Valve Seat

When ordering, Specify:

1. Ordering Code Number

2. Size of Valve

3. Type Number

4. Model Shown on Nameplate

Series 1156F-N256 Repair Kits

ORDERING CODE KIT NO. SIZES

884390 1156FRK 1⁄2 15
878339 N250RK

Kit for No. 1156F and 256 includes all items shown.

in. mm

3

⁄4 20

Limited Warranty: Watts Regulator Co. (the “Company”) warrants each product to be free from defects in material and workmanship under normal usage for a period of one year from the date of
original shipment. In the event of such defects within the warranty period, the Company will, at its option, replace or recondition the product without charge.

THE WARRANTY SET FORTH HEREIN IS GIVEN EXPRESSLY AND IS THE ONLY WARRANTY GIVEN BY THE COMPANY WITH RESPECT TO THE PRODUCT. THE COMPANY MAKES NO OTHER
WARRANTIES, EXPRESS OR IMPLIED. THE COMPANY HEREBY SPECIFICALLY DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

The remedy described in the first paragraph of this warranty shall constitute the sole and exclusive remedy for breach of warranty, and the Company shall not be responsible for any incidental, special
or consequential damages, including without limitation, lost profits or the cost of repairing or replacing other property which is damaged if this product does not work properly, other costs resulting
from labor charges, delays, vandalism, negligence, fouling caused by foreign material, damage from adverse water conditions, chemical, or any other circumstances over which the Company has no
control. This warranty shall be invalidated by any abuse, misuse, misapplication, improper installation or improper maintenance or alteration of the product.
Some States do not allow limitations on how long an implied warranty lasts, and some States do not allow the exclusion or limitation of incidental or consequential damages. Therefore the above
limitations may not apply to you. This Limited Warranty gives you specific legal rights, and you may have other rights that vary from State to State. You should consult applicable state laws to
determine your rights. SO FAR AS IS CONSISTENT WITH APPLICABLE STATE LAW, ANY IMPLIED WARRANTIES THAT MAY NOT BE DISCLAIMED, INCLUDING THE IMPLIED WARRANTIES OF

MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE LIMITED IN DURATION TO ONE YEAR FROM THE DATE OF ORIGINAL SHIPMENT.

Water Safety & Flow Control Products

IS-1156F 0829 EDP#1910265 © Watts, 2008

USA: 815 Chestnut St., No. , MA 01845-6098; www.watts.com

Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.ca