Walchem EZ Series User manual

Five Boynton Road Hopping Brook Park Holliston, MA 01746 USA
TEL: [phone] WEB: www.walchem.com
EZ Series Electronic Metering Pump
Instruction Manual
IWAKI PUMPS

Notice
© 2016 WALCHEM, Iwaki America Inc. (hereinafter “Walchem”)
Five Boynton Road, Holliston, MA 01746 USA
tel [phone] fax [phone]
All Rights Reserved
Printed in USA
Proprietary Material
The information and descriptions contained herein are the property of WALCHEM. Such information and
descriptions may not be copied or reproduced by any means, or disseminated or distributed without the
express prior written permission of WALCHEM.
This document is for information purposes only and is subject to change without notice.
Statement of Limited Warranty
WALCHEM warrants equipment of its manufacture and bearing its identication to be free from defects in
workmanship and material for a period of two years from date of delivery from the factory or authorized
distributor under normal use and service and otherwise when such equipment is used in accordance with
instructions furnished by WALCHEM and for the purposes disclosed in writing at the time purchased, if
any. WALCHEM’s liability under this warranty shall be limited to replacement or repair, F.O.B. Holliston,
MA U.S.A. of any defective equipment or part which, having been returned to WALCHEM, transportation
charges prepaid, has been inspected and determined by WALCHEM to be defective.
THIS WARRANTY IS IN LIEU OF ANY OTHER WARRANTY, EITHER EXPRESS OR IMPLIED, AS
TO DESCRIPTION, QUALITY, MERCHANT-ABILITY, FITNESS FOR ANY PARTICULAR PURPOSE
OR USE, OR ANY OTHER MATTER.
P/N E00159.M
January 2017

TABLE OF CONTENTS
Thank you for choosing a Walchem EZ Series metering pump. This instruction manual deals with the cor-
rect installation, operation, maintenance and troubleshooting procedures for the EZ metering pumps. Please
read through it carefully to ensure the optimum performance, safety and service of your pump.
Contents
1.0 INTRODUCTION ..................................................................................... 1
1.1 Safety and Caution Notes ................................................................................................................. 1
1.2 Principle of Operation........................................................................................................................ 1
1.3 Model Code ....................................................................................................................................... 2
1.4 Specications .................................................................................................................................... 2
1.4.1 Electrical .............................................................................................................................................. 2
1.4.2 Operating Conditions .............................................................................................................. 2
1.4.3 Capacity/Pressure Rating ....................................................................................................... 3
1.4.4 Adjustment Range................................................................................................................... 3
1.4.5 Materials of Construction ........................................................................................................ 3
1.5 Dimensions........................................................................................................................................ 4
2.0 INSTALLATION ....................................................................................... 6
2.1 Unpacking ......................................................................................................................................... 6
2.2 Location............................................................................................................................................. 6
2.3 Supply Tubing.................................................................................................................................... 7
2.4 Discharge Tubing .............................................................................................................................. 8
2.5 Installing Injection/BackPressure Valve............................................................................................. 8
2.6 Interlocking Pump.............................................................................................................................. 9
2.7 Electrical............................................................................................................................................ 9
3.0 OPERATION............................................................................................ 9
3.1 Priming .............................................................................................................................................. 9
3.2 Adjustment and Control..................................................................................................................... 10
3.3 Calibration ......................................................................................................................................... 13
3.4 STOP Function.................................................................................................................................. 13
3.5 AC Power Interruption ....................................................................................................................... 13
3.6 Auto Air Vent Valve Operation........................................................................................................... 14
3.7 MultiFunction Valve Operation .......................................................................................................... 14
4.0 MAINTENANCE ..................................................................................... 16
4.1 Diaphragm Replacement................................................................................................................... 16
4.2 Valve Replacement ........................................................................................................................... 16
4.3 Tubing ............................................................................................................................................... 16
5.0 EXPLODED VIEW & PARTS GUIDE......................................................17
6.0 TROUBLESHOOTING ............................................................................27
7.0 SERVICE POLICY...................................................................................27

1
1.0 INTRODUCTION
1.1 Safety and Caution Notes
Always wear protective clothing, eye protection and gloves before working on or near a metering pump. Follow
all recommendations of the supplier of the solution being pumped. Refer to the MSDS from the solution supplier
for additional precautions.
Walchem EZ Series metering pumps should be installed where ambient temperatures do not exceed 122°F
(50°C) or do not fall below 32°F (0°C). Pumps should always be shielded from direct exposure to the elements.
Black UV resistant tubing should be used if the tubing is exposed to strong UV radiation (sunlight/lamps).
WARNING Risk of electrical shock! This pump is supplied with a grounding conductor and grounding-type
attachment plug. To reduce the risk of electrical shock, be certain that it is connected only to a properly
grounded, grounding type receptacle with ratings conforming to the data on the pump data plate. Prior to
performing any maintenance on a pump, disconnect the pump from the electrical power source.
Plumbing Precautions
All tubing must be securely attached to the ttings prior to starting the pump (see Section 2.3). Only use
Walchem tubing with your pump. Tubing should be shielded to prevent possible injury in case of rupture or
damage. UV resistant tubing should be used if the tubing is exposed to UV light. Always adhere to local
plumbing codes and requirements. Be sure that the installation does not constitute a cross connection. Walchem
is not responsible for improper installations. Prior to performing any maintenance on a pump, depressurize the
discharge tubing.
In ooded suction, pumping downhill, or pumping into little or no system pressure installations, a back
pressure/anti-syphon device must be installed to prevent over-pumping or siphoning. Contact your Walchem
distributor for additional information.
Solution Compatibility
CAUTION! This pump has been evaluated for use with water only. The suitability of this pump for use with
liquids other than water (such as acids or alkalines) is the responsibility of the user. For liquids other than
water, select the best-suited liquid end material combination using a chemical compatibility chart.
1.2 Principle of Operation
The EZ series electronic metering pumps consist of a pump unit, a drive unit, and a control unit. The drive unit is an
electromagnetic solenoid. When the solenoid coil is energized by the control unit the armature shaft moves forward
due to the magnetic force of the solenoid. The shaft is attached to a PTFE faced diaphragm which is part of the pump
unit. The diaphragm is forced into the pump head cavity decreasing volume and increasing pressure which forces liquid
in the pump head out through the discharge check valves. When the solenoid coil is de-energized, a spring returns the
armature to its starting position. This action pulls the diaphragm out of the head cavity increasing volume and decreasing
pressure. Atmospheric pressure then pushes liquid from the supply tank through the suction check valves to rell the
pump head.

2
1.3 Model Code
EZ B16 D 1 - VC A
1 2 3 4 5 6
1 Pump Series
EZ: Electronic metering pump with manual speed control (adjustable to 360 strokes per minute)
2 Capacity/Pressure Rating (See Section 1.4 for detailed chart.)
3 Control Module
D: For use on all EZ models, features digitally adjustable speed and xed stroke length
T: Timer module allows daily, weekly, or 2 week operation with digitally adjustable speed and
external stop control. Available on 115V EZB models.
4 Voltage
1: 115 VAC, 50/60 Hz
2: 230 VAC, 50/60 Hz (not available on EZB pumps)
5 Liquid End (See Section 1.45 for detailed chart.)
6 Options
M: Multifunction Valve is supplied in place of the manual air vent valve. Available for the EZ
series pumps in all sizes and iquid ends except FC. Not available with the ADV feature.
A Auto Degassing Valve is supplied under the manual air vent valve. Available for the EZ Series
in B11/16/21 and C16/21 sizes with –VC/-VE liquid ends only.
1.4 Specications
1.4.1 Electrical
(50/60 Hz, single phase)
EZB 115 VAC±10% 0.9 Amp max. 16 watt avg.
EZC 115 VAC±10% 1.4 Amp max. 24 watt avg.
230 VAC±10% 0.6 Amp max. 24 watt avg.
1.4.2 Operating Conditions
Ambient temperature 32°F to 122°F (0°C to 50°C)
Relative humidity 30% to 90% non-condensing
Liquid temperature 32° to 104°F (0 to 40°C) for PVC based liquid ends
32° to 140°F (0 to 60°C) for PP, PVDF, SS based liquid ends

3
1.4.3 Capacity/Pressure Rating
Size Maximum
Output Capacity Max Output per
Stroke (mL)
Maximum
Pressure1
Connection
Size (in)
Tubing O.D
(Gal/hr) (mL/min) PSI MPa
B11 0.6 38 0.11 150 1.0 3/8
B16 1.0 65 0.18 105 0.7 3/8
B21 1.5 95 0.26 60 0.4 3/8
B31 3.2 200 0.56 30 0.2 1/2
C16 1.3 80 0.22 150 1.0 3/8
C21 2.0 130 0.36 105 0.7 3/8
C31 4.3 270 0.75 50 0.35 1/2
C36 6.3 400 1.17 30 0.2 1/2
1 Auto Degassing valve reduces output by approx. 20%
1.4.4 Adjustment Range
Frequency adjustment range: 0 to 360 strokes per minute
1.4.5 Materials of Construction
Liquid
End
Code
Pump
Head
& Fittings
Diaphragm Valve
Balls
Valve
Seat
Valve
Seals Gasket Tubing
PA GFRPP
PTFE
(bonded to
EPDM)
CE PCTFE AFLAS®
PTFE PE
PC GFRPP CE FKM FKM
PE GFRPP CE EPDM EPDM
VC PVC CE FKM FKM
VE PVC CE EPDM EPDM
VF PVC PTFE EPDM EPDM
TA PVDF CE PCTFE AFLAS®
TC PVDF CE FKM FKM
FC PVDF CE PCTFE PTFE
CE Alumina ceramic PE Polyethylene
EPDM Ethylene propylene diene monomer PTFE Polytetrauoroethylene
FKM Fluoroelastomer PVC Polyvinylchloride (translucent)
GFRPP Glass ber reinforced polypropylene PVDF Polyvinylideneuoride
PCTFE Polychlorotriuoroethylene

4
1.5 Dimensions
EZB Models with thermoplastic liquid end materials (except -FC)
7.95” (See Note 1)
1.85”
Tubing (ID x OD)
ø1/4” x ø3/8”
0.08” 3.21” (0.98”)
Tubing (ID x OD)
ø1/4” x ø3/8”
Tubing (ID x OD)
ø1/4” x ø3/8” 3.94”
0.20”
3.46”
0.24”
1.26”
0.28” 0.63”
0.39”
X
Y (See Note 2)
Z (See Note 3)
3.54”
EZB Models with FC liquid end materials
L
1/4” FNPT
ø3/8 OD Fittings
supplied
3.21”
0.08” (0.98”)
0.24”
1.26”
0.63”
0.28”
3.46”
3.94”
0.20”
E
X
Y
6.83”
3.54”
1/4” FNPT
ø3/8 OD Fittings
supplied
Model Size X Y Z
11-21 0.54" 6.1" 7.47"
31 -0.15" 6.57" 7.91"
Model Size X Y L E
11-21 1.20” 5.90” 6.57” 0.51”
31 0.55” 6.54” 6.81” 0.63”
Notes:
1. Addition of a Multifunction valve increases overall length by 0.10”.
2. Addition of a Multifunction Valve increases discharge height by 2.62”. The Auto Degassing Valve increases discharge height by 1.82”.
3. Addition of a Multifunction Valve increases overall liquid end height by 1.25”. The Auto Degassing Valve increases height by 1.82”

5
EZC Models with thermoplastic liquid end materials (except FC)
8.66” (See Note 1)
1.85”
Tubing (ID x OD)
ø1/4” x ø3/8”
Tubing (ID x OD)
ø1/4” x ø3/8”
Tubing (ID x OD)
ø1/4” x ø3/8”
4.13” (1.06”)
3.94”
0.59” 1.18” 0.59”
0.28”
0.59” 0.59”
Y (See Note 2)
4.57”
0.31”
3.94”
Z (See Note 3)
X
EZC Models with FC liquid end materials
L
E
4.13” (1.06”)
3.94”
0.59” 1.18” 0.59”
0.28”
0.59” 0.59”
Y (See Note 2)
4.57”
0.31”
3.94”
Z (See Note 3)
X
1/4” FNPT
ø3/8 OD Fittings
supplied
1/4” FNPT
ø3/8 OD Fittings
supplied
Model Size X Y Z
16-21 0.94" 6.46" 7.83"
31-36 0.24" 6.95" 8.33"
Model Size X Y L E
16-21 1.57” 6.31” 7.32” 0.51”
31-36 0.91” 6.97” 7.44” 0.63”
Notes:
1. Addition of a Multifunction valve increases overall length by 0.10”.
2. Addition of a Multifunction Valve increases discharge height by 2.62”. The Auto Degassing Valve increases discharge height by 1.82”.
3. Addition of a Multifunction Valve increases overall liquid end height by 1.25”. The Auto Degassing Valve increases height by 1.82”

6
2.0 INSTALLATION
2.1 Unpacking
Open the shipping carton and inspect contents for damage. If any items are missing or damaged contact your local
distributor.
Pumps are pre-primed with water at the factory. If the application is not compatible with water, drain
and dry before use. Be sure to remove caps from ttings before attaching tubing.
CAUTION: Head bolts may have loosened during storage or shipment. Be sure to check and tighten
to 19 lb-in torque, if necessary.
Do not handle or move the pumps using the Control Module only. The pump should be supported by the base or drive
unit during handling
2.2 Location
Choose a location for the pump which is clean, dry, vibration-free, close to an electrical outlet, and allows convenient
access to stroke length control, frequency control, and tubing connections. Avoid areas where ambient temperature
exceeds 122°F (50°C) or falls below 32°F (0°C). Pumps should always be shielded from direct exposure to the ele-
ments. Black UV resistant tubing should be used if the tubing is exposed to strong UV radiation (sunlight/lamps).
This pump is cord connected and not intended for permanent mounting to a building structure. However, temporary
mounting to stabilize the pump during operation may be necessary as long as tools are not required for the installation
or removal of the pump.
Flooded suction (mounting the pump below the level of liquid in the supply tank) is strongly recommended, especially
when pumping liquids that readily generate gas bubbles. Sodium hypochlorite and hydrogen peroxide are common
examples of such liquids. (See Figure 1.)
Figure 1 Flooded suction
Recommended for liquids
that out-gas
Figure 2 Shelf mount Figure 3 Tank mount
If ooded suction mounting is not possible, a shelf adjacent to (but not directly above) the supply tank often works
well. (See Figure 2.) The supply tank or cover can also be used if it has provisions for mounting a pump. (See Figure
3.) In any case, the total suction lift should not exceed 5 ft (1.5m).

7
Foot Valve
PVC Pipe Tubing Straightener
(user supplied)
or
Ceramic weight
Air Gap
Return Line
Point of
Injection
Injection
Valve
Coupling Nut
Coupling Nut
(Air Vent Valve)
Coupling Nut
Figure 4 Connection Tubing
2.3 Supply Tubing
The supply tubing run should be as short as possible. For ooded suction mounting, install a shut-off valve with an
appropriate tubing connector at the tank outlet. Cut a length of tubing from the coil supplied and install between
the shut-off valve and the pump inlet tting. For suction lift applications, slide on the ceramic weight, then install a
foot valve on one end of suction tubing. Cut the tubing to a length such that the foot valve hangs vertically about 1 in
(25mm) above the bottom of the tank. Avoid any loops in the tubing run that could form a vapor trap. Running the
tubing through a length of pipe will help to keep tubing straight. Total vertical suction lift should be no more than 5ft.
(1.5m). Reference Figure 4.
Attach tubing as shown in Figure 5. First slide the coupling nut, small end rst, then the tubing clamp onto the tubing.
Push the tubing over the tubing adapter tip all the way to the valve housing shoulder. (Tip: if the tubing is stiff from
cold, dip the tubing end in hot tap water for a few minutes so it will slide on and are out more easily. Push the tubing
adapter into the tting on the pump and coupling nut onto the threads. Apply some pressure on the coupling nut and
tubing while tightening the nut, making sure the tubing has not backed off of the shoulder of the valve housing.
Figure 5
Fitting
on pump
Tubing
adapter
Tubing
Coupling
Nut
Slide
tubing
down
Tubing clamp
WARNING: All ttings and coupling nuts should be tightened by hand only. If necessary, a small tool may
be used to make it snug. DO NOT use excessive force or large wrenches.
The coupling nut should not bottom out completely against the tting. If this happens during connection, check the
tubing and tubing clamp connection. Remove the coupling nut, re-cut the tubing and re-connect if necessary.
WARNING: If there is any leakage around the coupling nut and it appears to have been installed correctly,
DO NOT TIGHTEN the coupling further! Release pressure in the line, disconnect tubing, re-cut and re-connect.
Tightening of misinstalled tubing may cause the tubing to be cut off under pressure.

8
2.4 Discharge Tubing
Cut a length of tubing long enough to go from the pump to the application (injection) point. Additional tubing can be
ordered from your distributor. Avoid sharp turns or bends and hot surfaces. Routing tubing through rigid pipe such
as PVC pipe is recommended for long runs and/or as protective shielding against corrosive chemicals. If applicable,
install the injection valve in 1/2” NPT thread at the injection point (see section 2.5) and connect the discharge tubing
to the injection valve.
Attach tubing as described in section 2.3 and as shown in Figures 5 and 6. Note: Some models have an air vent valve
with two outlet connections. The connection marked ‘OUT’ is the discharge side to the application point. (Fig 6).
Attach a second length of tubing to the air vent side marked (‘AIR’) and route back to the chemical solution tank or
drum. On the larger pumps (31 & 36 sizes), the air vent valve connections are not marked, however, the discharge
side is the vertical (UP) connection and the air vent connection is on the side of the valve.
"AIR"
"OUT"
Drains back to tank
Discharges to injection point
Figure 6 Air Vent Valve Tubing
2.5 Installing Injection/BackPressure Valve
A tting or tee with 3/8”or 1/2” NPTF threads and with sufcient depth will accept the injection valve assembly. If
required, trim off an amount of the extension tip until it ts your tting or tee. (Fig. 7.)
The position of the injection/back pressure valve can be at any orientation as long as the spring is retained in the
valve. DO NOT REMOVE THE SPRING. Be sure to check and replace the spring as needed. Attach the tubing fol-
lowing the same instructions in section 2.3, connecting the supply tubing.
CAUTION: Some chemicals may have reactions as they are injected into the main ow. For exam-
ple, sulfuric acid may react with water causing excess heat. If the chemical is heavier than water, mount the
injection valve as close as possible to vertical coming into the bottom of the pipe. This will keep the injection
nozzle facing up and keep the heavier chemistry from draining into the pipe and causing adverse reactions
within the injection valve and pipe.
In addition to preventing backow from pressurized lines, the injection valve acts as a back pressure valve when
pumping into atmosphere or low pressure applications. However, the back pressure by the injection valve can vary
and the valve does NOT act as an anti-siphon valve. If siphoning is a possibility, or if pumping downhill into open
atmosphere (open tank), a Walchem MultiFunction valve or a separate back pressure/anti-siphon valve must be in-
stalled.
Note: Siphoning can also occur at the tip of the injection valve because of the high ow rate in the main pipe owing
past the small injection nozzle (venturi effect). In this case, an anti-siphon device must be installed to avoid over
feeding or siphoning of chemistry. See Section 5.0 for complete liquid ends parts list and exploded view.

9
Outer Diameter 1/2"
1/2" NPT
3/8" NPT
Trim back as needed to t
tee or tting
Figure 7 Injection Valve
2.6 Interlocking Pump
CAUTION! Control of pump operation is critical. Operation and chemical addition during no ow
situations can create hazardous situations from elevated chemical concentrations and chemical gasses trapped
in the line.
Ensure that during no ow conditions such as when the well pump, main line or recirculation pump is off, and for
pools/spas, in times of backwash, that the metering pump is not allowed to operate. If using a controller (pH/ORP/
pool) for automated control and ow indication is tied into it, pump operation can be interlocked to the controller.
Interlocking the pump operation can also be done directly using a ow switch located in the water, main or pool/spa
recirculation lines. The ow switch can be tied directly into the pumps to stop operation during no ow conditions.
2.7 Electrical
WARNING Risk of electrical shock! This pump is supplied with a grounding conductor and ground-
ing-type attachment plug. To reduce the risk of electrical shock, be certain that it is connected only to a prop-
erly grounded, grounding type receptacle.
CAUTION! The electronics within the pump can be damaged by excessive surges in voltage. Do
not install the pump near high-power electrical equipment that generate high surge voltages. Avoid branch
circuits that also supply power to heavy or other equipment that could generate electrical interference. If nec-
essary, install a surge suppression device (such as a varistor with a resistance greater than 2000A) or a noise
reducing transformer at the pump’s power connection.
3.0 OPERATION
3.1 Priming
Install the pump as described above. With the pump turned on, set frequency at 100%. If the pump is equipped with
an air vent valve, open the knob 1/2 turn. Liquid should move through the suction tubing and into the pump head.
When liquid starts running through the vent side tubing, close the air vent knob and continue with output adjustment
described below. If the pump has no air vent valve, disconnect the discharge tubing from the injection valve. When
liquid enters the discharge tubing at the pump head, stop the pump. Then reconnect the discharge tubing to the injec-
tion valve.
If the pump does not self prime, remove the check valve housing on discharge & suction sides to make sure valve
cartridges and gaskets are in correct positions (see section 4.2 for correct orientation).
Note: It is recommended that pumps with FC liquid ends use ooded suction when priming, due to the hard valve seat
material.

10
3.2 Adjustment and Control
3.2.1 EZ Pumps using the ‘D’ Control Module
If less than full output is required, set the frequency to the appropriate percentage of maximum desired.
Example: Model EZB21D1-VE has maximum output of 1.5 GPH.
Desired output is 1.2 GPH. 1.2 ÷ 1.5 = 0.8 or 80%
Set the frequency of the pump to 0.8 x 360 = 288 spm by pushing the UP or DOWN
arrow keys.
3.2.2 EZ Pumps using the ‘T’ Control Module
The EZB-Timer Series is able to operate in Daily, Weekly and 2-Week modes. An external stop input and
12VDC output are also available.
Timer Display/Keypad Overview
4
2
3
5
6
7
8
Power
Ground
Stop Input
Sensor Power
DC 12V
20 mA max.
+
_
White
NEU
Black
HOT
Green
Figure 8
MODE key. Scrolls user
through TIMER, WAIT
and MAN modes. Use to
exit from any programming
mode.
SEL. Manually starts or stops
the pump from WAIT mode.
Used to select program number
or day of week while program-
ming.
NUM/DAY indicator. Becomes
backlit when programming
or operating at programmed
number/day.
NUM indicator. Becomes
backlit when the pump is in
DAILY mode to indicate the
timer program number.
SET indicator. Becomes
backlit when pump is being
programmed.
2nd indicator. Becomes
backlit when pump is in the
2nd week of the 2-WEEK
mode.
UP/HOUR. Increases
numeric values and sets
the hours. Used with SEL
key to set pump on-time
and duration.
DOWN/MIN key. Decreases
numeric values and sets the
minutes. Used with SEL key to
select the Timer Pump Mode.
ON light. Indicates AC
power to the pump with
continuous green. Flashes
off with each stroke.
P 3 6 0
EH-T Controller
5.THU
6.FRI
7.SAT
8.STOP
2nd
ON
SEL
1.SUN
2.MON
3.TUE
4.WED
SET
ON
Num
MODE
HOUR
MIN
Alphanumeric display. Indicates
WAIT mode, stroke frequency, time
or pump on-time.

11
EZ-T Quick Reference Guide
FROM:
PRESS:
TO:
Mode Key
Select Key
WAIT
MENU
+
+
Move to MANUAL menu
Changes pump frequency (1 to 360 SPM)
Starts and stops manual operation
OR
Sets the Hour (incrementing only)
(Hold for 3 seconds)
MODE
SEL
MODE
SEL
SEL
SEL
MIN
HOUR
Move to TIME / DATE setting menu
Move to TIMER programming menu
Move to TIMER MODE selection menu
MANUAL
MENU
MIN
HOUR
SEL
TIME / DATE
MENU
(24 Hour Clock)
MIN
HOUR
SEL
Sets the Minutes (incrementing only)
Selects the Day of the week
MODE
MODE
Move to TIMER RUN mode (shows TIME)
Exits back to WAIT menu
Move to WAIT menu
MODE
TIMER RUN MENU
Scrolls between DAILY, WEEK or 2-WEEK
Timer modes
TIMER MODE MENU
MIN
HOUR
MODE
Exits back to WAIT menu
OR
TIMER
P
ROGRAMMING
MENU
Sets the Hour / Sets On-Time Minutes
MIN
HOUR
SEL
Sets the Minutes / Sets On-Time Minutes
Scrolls through the week days / program #
MODE
Exits back to WAIT menu
WAIT
MANUAL
TIMER RUN
POWER ON
TIMER MODE
SELECTION
TIMER
PROGRAMMING
MODE
MODE
HOUR
SEL
+
MIN
SEL
+
MODE
MODE
MODE
TIME / DATE
SETTING
SEL
(
3 Seconds
)
MODE

12
Programming and Timer Use
CAUTION! Before use, check the time and date. Set to the local time and date before programming.
Incorrect time/date can result in incorrect operation.
1. Manual Operation
From the WAIT menu, pressing the MODE key will enter the manual mode. Pressing SEL will toggle the
pump on and off manually. The speed can be changed with the UP and DOWN arrows both running and
waiting. NOTE: The pump speed set in this menu will be the speed that the pump will run during timed oper-
ations.
2. Time/Date Setting
From the WAIT menu, holding the SEL key down for 3 seconds will enter into the Time/Date SET menu.
Using the HOUR and MIN keys, the time can be set using a 24-hour clock. The SEL key will cycle through
the days of the week.
Once the correct time and day of the week are set, pressing the MODE key will go back to the WAIT menu.
3. Timer Mode Selection
Pressing the MIN and SEL keys at the same time will bring up the Mode Selection menu. This menu is where
the Timer module is set to control in daily, weekly, or in 2-week modes. Use the UP and DOWN keys to cy-
cle through the three options and MODE to get back to the WAIT menu. Daily mode allows a max of up to 8
timed operations repeated every day. Weekly and 2-week modes allow a max of one timed operation per day.
4. Timer Operation Programming
Pressing the HOUR and SEL keys at the same time will bring up the Timer Programming menu. This menu is
where the individual operations are set – both start time and run time.
DAILY MODE:
Initially, the 1-SUN and NUM will both be backlit. NUM is backlit to signal that the number backlit is
used – i.e. program 1 in this case. Using the HOUR and MIN keys, the time for the rst program can
be set (24-hour clock). Pressing the SEL key will change the menu to program the on-time to run the
pump (initially shows “ 0M”). Use the UP and DOWN keys to program the # of minutes for the pump
to run. Pressing SEL again will then move to program the second program and the backlight will move
from 1-SUN to 2-MON. The clock and on-time settings are set in the same manner. Pressing MODE
will go back to the WAIT menu.
WEEKLY MODE:
Initially, the 1-SUN will be backlit signifying that Sunday is being programmed. If a program is de-
sired for Sunday, use the HOUR and MIN keys to set the time of the program. If no program is desired
for Sunday, pressing the SEL key will scroll through each day’s two programmed settings – the time to
start and the run time. Pressing MODE will go back to the WAIT menu at any point in the program-
ming.
2-WEEK MODE:
Two week mode is similar and set just as the weekly mode, only after the rst 7-SAT is programmed or
passed by and 1-SUN is again backlit, the “2nd” will also become backlit showing that the day is in
the 2nd week. All programming functions are the same and SEL will scroll through each setting. Press-
ing MODE will go back to the WAIT menu at any point in the programming.
From the WAIT mode, pressing MODE will move to the MANUAL menu. Check to make sure that the pump
speed is set at the rate desired during the timed operations. If not, use the UP and DOWN keys to change the
pump speed.
Pressing MODE again will display the current time and date. The pump is now operating in the TIMER mode
and will come on at the next programmed timer operation.

13
3.3 Calibration
If exact output calibration is required, rst prime and adjust the pump as above. Then connect a calibration column to
the suction side of the pump. Turn the pump on for one minute and read the amount of liquid pumped from the col-
umn. Adjust the frequency up or down as necessary and check the output again. When the desired output is reached,
disconnect the calibration column and reconnect the suction tubing. (See Figure 9) Calibration must be performed
with application equivalent back pressure for accurate results. Published ow rates are based on maximum pressures.
Lower back pressures may result in slightly higher pump ow rates.
Figure 9 Calibration
3.4 STOP Function
Additionally, EZ pumps with a Timer Module can be controlled in start-stop mode. In this mode, AC power is applied
continuously and pump operation is stopped by completing the circuit between the positive ‘stop’ and common termi-
nals inside the T Control Module: 7 (positive) and 8 (common). A switch or solid state device capable of switching
5VDC at 2 mA should be used. Switch closed = pump stopped, switch open = pump running at the speed determined
by the frequency setting. This feature eliminates the need for a high voltage, high current AC relay to start and stop
the pump. (See Figure 8)
3.5 AC Power Interruption
If AC power is interrupted, the pump will power up as shown below:
State preceding power OFF State following power ON
WAIT WAIT
Running in Manual Operation Running in Manual Operation
Running in Timer Operation Running in Timer Operation
Setting Time WAIT
Programming Timer Set points WAIT

14
3.6 Auto Degassing Valve Operation
The Auto Degassing Valve (ADV) is an option on select EZ pumps and is added under the standard Manual Air Vent
Valve when ordered. It is used primarily in applications where gassing is a problem and pumps can lose prime.
Unlike the Manual Air Vent Valve, the Auto Degassing Valve constantly bleeds a controlled amount of volume out
of the “Air” vent. Therefore, the “Air” vent should always be plumbed back to the source tank. During priming, the
access knob does not have to be loosened as with a manual air vent valve as pressure is relieved through the vent.
The check valve assembly in the ADV uses a bottom seat to ensure that air is not introduced into the discharge media
and utilizes a second top seat that allows air to be quickly purged but limits the amount of liquid returned to the tank.
Moving the pump check valves above the ADV maintains back pressure within the pump discharge, but allows the
pump head to bleed, helping to speed the purging of air and auto re-priming the pump.
Vent port
Suction port
Check Valve
Automatic
Degassing Valve
Pump head
Discharge check
valves
Manual air vent valve
Disharge
port
AAVV – Cross Sectional View

15
3.7 MultiFunction Valve Operation
The MultiFunction Valve is optional on select E-Series pumps and replaces the standard Manual Air Vent Valve when
ordered. It integrates the air venting/bleeding functions with a back pressure, anti-siphon, and pressure relief valve.
For more detailed specications of the MultiFunction Valve, see its separate instruction sheet at walchem.com.
Air Vent / Bleed Function
1. Open the air vent by turning the relief valve knob 90 degrees to the “AV” position.
2. Operate the pump until all of the air is purged and only liquid is discharged from the air vent drain.
3. Turn the relief valve knob back 90 degrees to the “RV” position to set pressure relief.
AV
AV
RV
RV
AV
AV
RV
RV
AV
AV
RV
RV
Pressure Relief
Set
Pressure Relief
Relieved
RV
RV
AV
AV
Pressure Relief
1. In the “RV” position, the diaphragm under the relief valve knob provides a safety relief if the discharge line
pressure gets too high.
Line Pressure Relief
1. By rotating both the Relief valve knob to “AV” and the back pressure valve knob to “PF”, both the discharge line
and the pump head pressures are released out the air vent for full line pressure release.
Back Pressure / Anti-Siphon Valve
1. A spring-loaded diaphragm under the back pressure knob automatically adds approximately 36PSI (15 PSI
for low pressure versions) of back pressure to the discharge side of the pump when the knob is set to the “BP”
position.
2. The diaphragm also prevents siphoning of chemical through the pump.
PF
PF
BV
BV
BV
BV
PF
PF
PF
PF
BV
BV
PF
PF
BV
BV
Back Pressure
Set
Back Pressure
Relieved
CAUTION: Conrm that liquid is discharged from the air vent drain. If the liquid is not discharged, the pres-
sure may not be released. If this is the case, repeat the Pressure Relief procedure.

16
4.0 MAINTENANCE
CAUTION! Before working on the pump, disconnect the power cord, depressurize the discharge tub-
ing and drain or ush any residual liquid from the pump head and valves. Always wear protective gear when
working around chemicals.
4.1 Diaphragm Replacement
Disconnect AC power to the pump and disconnect the suction tubing, discharge tubing, and air vent tubing. Remove
the four head bolts with a 4mm hex wrench. Unscrew the diaphragm and remove its retainer (small disk behind the
diaphragm). CAUTION: There may be small brass spacers between the retainer and the armature shaft. These
spacers need to be reused when replacing the diaphragm. Install the new retainer and diaphragm on the shaft. Turn
the diaphragm clockwise until it bottoms on the shaft. Use caution when handling the diaphragm – the PTFE surface
can be damaged by tools, nails or any sharp objects. Replace the pump head and tighten the head bolts to a torque of
19 lb-in (2.16 N-m).
4.2 Valve Replacement
Remove the suction and discharge tubing making sure discharge side has been
depressurized. Remove the suction tting, two valve cartridges, o-ring and gas-
ket(s). Install the new o-ring, gasket(s) and valve cartridges. Be sure both valve
seats are in the same orientation. Refer to Figure below. Tighten the suction
tting. Similarly remove and replace the discharge valve cartridges, o-ring and
gasket(s). For a more detailed drawing, refer to the Section 6.0.
CAUTION: There are many small parts in the liquid end.
These parts must be installed correctly for proper operation of the
pump.
4.3 Tubing
Check ends of tubing for splits, cracks, or thin spots. Examine the full length of
tubing for damage due to chang, abrasion, stress cracks, excessive temperature
or exposure to ultraviolet light (direct sunlight or mercury vapor lamps). If any
signs of deterioration exist, replace the entire length of tubing. It is a good idea to
replace discharge tubing on a regular preventive maintenance schedule every 12 months.
Valve seat
Valve guide
Valve ball
FLOW
Gasket

17
5.0 EXPLODED VIEW & PARTS GUIDE
PVC/GFRPP Liquid End Exploded View
For EZ pump model sizes 11-36
99
4
4
31
31
29
29
30
30
31
30
29
19 1
4
3
12
13
11
12
13
11
14
17
14
11
13
12
11
13
12
17
23
26
25
10
27
5
4
6
4
7
918
24
29
30
31
29
30
31
C Entire Head Assembly
D Valve Cartridge
F Multifunction Valve
Part numbers for these assemblies are on Page 26