Webstone® E-X-P
™
Series service valve kits are designed to simplify the installation and
maintenance of tankless water heaters (TWH) or the domestic hot water output of combi
boilers. A variety of models, kits, pressure relief valves (PRV), and accessories are
available to provide solutions for most installation needs.
IMPORTANT: Follow all federal/national, state, and local codes when installing,
testing, or performing work on systems. All parts are covered by a warranty against
manufacturing defects, provided they are installed by a licensed plumber and operated
under normal working conditions. If you have any questions or comments, please
contact us at (800) 225-9529 or visit us on the web at www.webstonevalves.com.
WARNING: Drain valves (if applicable) should remain closed during normal operation.
Do not rely on the drain cap to stop the water from draining. When draining, always
remove drain caps slowly to insure that no pressure exists.
Boiler Hydronic Connections: E-X-P Series service valves may be used for boiler
connections, only when paired with a boiler-specific pressure relief valve with suitable
pressure and BTU specifications (i.e. Webstone Item # H-20733, included in PR3 kits). See
boiler manual for system requirements.
It is recommended that these instructions be stored along with other documents related
to your heating appliance's installation and maintenance.
INSTALLATION - refer to drawings at right for model details
1. Apply PTFE tape or sealant to any threaded pipe connections.
2. For installations utilizing PRV relocation adapter
appliance hot outlet. Ensure PRV Port Plug
Note: PRV relocation adapter
with E-X-P E2™ service valves.
3. For installations with Pressure Relief Valve:
Thread Pressure Relief Valve
adapter
D
as applicable. For item H-20723-CN Commercial PRV (sold separately)
thread PRV body onto the close nipple until tight. Then thread the other end of the
close nipple onto
B
LET
4 Loosen Union Nut on Hot Valve
hot outlet. If nut is removed, carefully reassemble as shown. Ensure washer or
o-ring is positioned correctly and undamaged.
UNION NUT
5. Position Hot Valve
B
COLD UNION
FITTING
15 ft/lbs of torque.
w/ Blue Insulator
WASHER
6. Repeat steps 4 and 5 for the Cold Valve
heating appliance cold inlet.
A
7. Connect Cold Valve
COLD VALVE
8. Connect Hot Valve
B
9. Ensure that both drain valve lever handles are in the closed position
(perpendicular to the drain portion of the body).
PRV INSTALLATION REQUIREMENTS & MAINTENANCE
WARNING: A suitable pressure relief valve (PRV) is required for all installations, see
heating appliance installation manual for specific system requirements.
The PRV must be installed in Hot Valve
port integrated directly into the heating appliance. Installation must maintain a 3/4"
port size with no shut-off valve or line restriction in-between the appliance and the PRV.
The discharge line from the PRV should pitch downward and terminate 6" above drains,
or per local code height, where discharge will be clearly visible. The discharge end of
the line shall be plain (unthreaded) and a minimum of 3/4" in diameter. The discharge
LET
line material must be suitable for water at least 180°F. The discharge line shall be as
short and straight as possible such that the arrangement does not reduce the relieving
capacity of the pressure relief valve. No valve of any type may be installed in the
discharge line of the pressure relief valve.
It is recommended that the PRV is manually operated once a year. In doing so, it will be
necessary to take precautions with regard to the discharge of potentially scalding hot
A
water under pressure. Ensure discharge has a place to flow. Contact with your body or
COLD VALVE
other property may cause damage or harm.
INSTALLATION
INSTRUCTIONS
HOT OUTLET
UNION NUT
HOT UNION FITTING
w/ Red Insulator
WASHER
PRV PORT
D
, thread
E
is installed in Hot Valve
C
D
takes the place of hot union fitting when installed
PRESSURE
RELIEF VALVE
B
HOT VALVE
C
into the Hot Valve
B
or
D
.
HOT OUTLET
B
and connect union fitting to heating appliance
UNION FITTING
WASHER
as desired. Tighten union nut using approximately
UNION NUT
PRV PORT*
, connecting to
A
C
to cold water supply.
A
PRESSURE
RELIEF VALVE
B
to hot water piping.
HOT VALVE
Red Drain Handle
PRV port, PRV relocation adapter
B
HOT OUTLET
UNION FITTING
WASHER
UNION NUT
B
HOT VALVE
W W W . W E B S T O N E V A L V E S . C O M
Red Drain Handle
COLD INLET
UNION NUT
COLD UNION
FITTING
w/ Blue Insulator
WASHER
D
on heating
A
B
PRV port.
COLD VALVE
PRV port or PRV relocation
COLD INLET
UNION FITTING
WASHER
UNION NUT
A
COLD VALVE
Blue Drain Handle
D
, or PRV
COLD INLET
UNION FITTING
WASHER
UNION NUT
A
COLD VALVE
Blue Drain Handle
HOT OUTLET
UNION NUT
HOT UNION FITTING
w/ Red Insulator
WASHER
PRV PORT
C
PRESSURE
RELIEF VALVE
B
HOT VALVE
HOT OUTLET
Refer to E-X-P E3
™
UNION FITTING
drawing below
if installing with
WASHER
H-28023W PRV
Relocation Adapter
UNION NUT
PRV PORT*
C
PRESSURE
RELIEF VALVE
B
HOT VALVE
Red Drain Handle
* Available without PRV port for appliances with integrated PRV Ports
HOT OUTLET
PRV RELOCATION
D
ADAPTER
C
WASHER
PRESSURE
UNION NUT
RELIEF VALVE
PORT
E
PLUG
PRV PORT
B
HOT VALVE
Red Drain Handle
B
For appliances with
top or bottom mounted
HOT VALVE
water connections
Red Wing Handle
and integrated PRV
O-RING
and drain ports
UNION
FITTING
UNION NUT
HOT OUTLET
COLD INLET
UNION NUT
COLD UNION
FITTING
w/ Blue Insulator
WASHER
A
COLD VALVE
COLD INLET
UNION FITTING
WASHER
UNION NUT
A
COLD VALVE
Blue Drain Handle
COLD INLET
UNION FITTING
WASHER
UNION NUT
A
COLD VALVE
Blue Drain Handle
A
COLD VALVE
Blue Wing Handle
O-RING
UNION
FITTING
UNION NUT
COLD INLET
WARNING: Cancer and Reproductive
Harm - www.P65Warnings.ca.gov