Walchem EHE Operating Manual

EHE Series

Electronic Metering Pump

Instruction Manual

W A L C H E M

IWAKI America Inc.

EHE Series Metering Pumps

Five Boynton Road Hopping Brook Park Holliston, MA 01746 USA

TEL: [phone] FAX: [phone] WEB: www.walchem.com

Notice

© 2017 WALCHEM, Iwaki America Inc. (hereinafter “Walchem”)
Five Boynton Road, Holliston, MA 01746 USA
tel [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 identification 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, MERCHANTABILITY, FITNESS FOR ANY PARTICULAR
PURPOSE OR USE, OR ANY OTHER MATTER.

P/N E00022.U
March 2017

TABLE OF CONTENTS

Thank you for choosing a Walchem E Series metering pump. This instruction manual deals with the correct
installation, operation, programming maintenance, and troubleshooting procedures for the EHE Series metering
pumps. Please read through it carefully to ensure the optimum performance, safety and service of your pump.

1.0 INTRODUCTION ............................................................................................................. 1

1.1 Safety and Caution Notes ............................................................................................ 1

1.2 Principle of Operation ................................................................................................... 1

1.3 Specifications ............................................................................................................... 2

1.4 Dimensions .................................................................................................................. 3

2.0 INSTALLATION ............................................................................................................... 5

2.1 Unpacking .................................................................................................................... 5

2.2 Location ....................................................................................................................... 5

2.3 Supply Tubing .............................................................................................................. 7

2.4 Discharge Tubing ......................................................................................................... 8

2.5 Installing Injection Check Valve .................................................................................... 8

2.6 Interlocking Pump ........................................................................................................ 9

2.7 Electrical ...................................................................................................................... 9

3.0 OPERATION ................................................................................................................. 10

3.1 Priming ....................................................................................................................... 10

3.2 Adjustment ................................................................................................................. 10

3.3 Calibration .................................................................................................................. 10

3.4 Control Unit Operation and Programming .................................................................. 10

3.5 Input Wiring and Connections .................................................................................... 21

3.6 AC Power Interruption ................................................................................................ 22

4.0 MAINTENANCE ............................................................................................................ 23

4.1 Diaphragm Replacement ............................................................................................ 23

4.2 Valve Replacement .................................................................................................... 23

4.3 Tubing ........................................................................................................................ 23

5.0 EXPLODED VIEW AND PARTS GUIDE ....................................................................... 24

5.1 How to order parts for your metering pump. ............................................................... 24

5.2 Accessories (Not shown) ............................................................................................ 24

5.3 EHE31, 36, 46 Liquid End Exploded View .................................................................. 25

5.4 EHE 56 Liquid End Exploded View............................................................................. 27

5.5 EHE 36-HV Liquid End Parts List ............................................................................... 29

5.6 Drive Control Components ......................................................................................... 30

5.7 Assembly Part Numbers ............................................................................................. 30

5.8 Spare Parts Kit ........................................................................................................... 31

6.0 TROUBLESHOOTING ................................................................................................... 32

7.0 SERVICE POLICY ......................................................................................................... 32

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 E Series metering pumps should NOT be installed where ambient temperatures exceed
122°F (50°C) or 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 fittings 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.

If you are pumping downhill or into little or no system pressure, a back pressure/anti-siphon device
must be installed to prevent over-pumping. Contact your Walchem distributor for additional
information.

Solution Compatibility

CAUTION! This pump has been tested by Underwriters Laboratories Inc. using water only. The

suitability of this pump for use with liquids other than water is the responsibility of the user. For
liquids other than water, select the best-suited liquid end material combination using a chemical
compatibility chart or guidance from the solution supplier.

1.2 Principle of Operation

The E Series electronic metering pump consists 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 refill the pump head.

2

1.3 Specifications

EH E36 E 1 - PC V

1 2 3 4 5 6

1 Pump Series

EHE Electronic metering pump with external Analog and pulse control or manual speed

control (adjustable to 360 strokes per minute). Manually adjustable stroke length.
(Turndown ratio 1800:1)

2 Capacity/Pressure Rating

Size

Output Capacity

Output per stroke

(mL)

Maximum

Pressure

Conn. Size (in)
Tubing O.D.

(GPH)

(mL/min)

min

max

min

max

min

max

(PSI)

(MPa)

E31

0.0031

5.5

0.189

340

0.189

0.94

150

1.0

½

E36

0.0047

8.5

0.289

520

0.289

1.44

105

0.7

½

E46

0.0067

12.0

0.417

750

0.417

2.08

60

0.4

½

E56

0.0111

20.0

0.694

1250

0.694

3.47

30

0.2

½

E36-HV

0.0033

4.0

0.210

252

0.210

1.05

73

0.5

½ OD x ½ ID (Suc)

E46-HV

0.0067

8.0

0.421

505

0.421

2.10

60

0.4

½ OD x ½ ID (Suc)

3 Control Module

E For use on all EHE models, features analog and external pulse control with pulse

divide and multiply capability.

4 Voltage

1 115VAC, 50/60 Hz

2 230VAC, 50/60 Hz

5 Liquid End

Liquid End

Code

Pump Head &

Fittings

Diaphragm*

Valve

Balls

Valve Seat

Valve
Seals

Gasket

Tubing

HV

PVC

PTFE

SS/HC

PCTFE

FKM

PTFE

N/A

VC

PVC

PTFE

CE

FKM

FKM

PTFE

PE

VE

PVC

PTFE

CE

EPDM

EPDM

PTFE

PE

VF

PVC

PTFE

PTFE

EPDM

EPDM

PTFE

PE

PC

GFRPP

PTFE

CE

FKM

FKM

PTFE

PE

PE

GFRPP

PTFE

CE

EPDM

EPDM

PTFE

PE

FC

PVDF

PTFE

CE

PCTFE

PTFE

PTFE

PE

VM

M-PVC

PTFE

CE

FKM

PTFE

PTFE

PE

 E56 Model only * Bonded to EPDM

Materials of Construction

CE Alumina ceramic PCTFE Polychlorotrifluoroethylene
EPDM Ethylene propylene diene monomer PE Polyethylene
FKM Fluoroelastomer PTFE Polytetrafluoroethylene
GFRPP Glass fiber reinforced polypropylene PVC Polyvinylchloride (translucent)
M-PVC Machined polyvinylchloride PVDF Polyvinylidenefluoride

HC Hastelloy C276 (spring in HV)

6 Special Head Options

Blank

=

1/2” O.D. tube connection and standard accessories. (HV is 1/2” O.D. discharge x 1/2” I.D. suction)
V = Standard 1/2” tube connections with back pressure/anti-syphon valve added. (Not available on FC models)
T = 3/4” NPT (male) pipe thread connection. (1/2” MNPT on HV pumps). No MAVV.
P = 3/4” NPT (male) connection (1/2” MNPT on HV pumps) with back pressure/anti-syphon valve. No MAVV.

Note: NPT piping connection material of construction will be the same as the liquid end. All pumps include a
manual air vent valve with the exception of FC/HV liquid ends and options P and T.
All pumps include one foot valve, one injection valve, 20 feet of polyethylene tubing and one ceramic weight
with the exception of HV models (tubing only) and options P and T.

3

Adjustment Range

Stroke length adjustment range 20% to 100% Stroke Length
Frequency adjustment range 1 to 360 strokes per minute (1 to 240 strokes per minutes for –HV)

Operating Conditions

Ambient temperature 32 to 122°F (0 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 or PVDF based Liquid Ends

1.4 Dimensions

PVC & GFRPP Models

Model

A B C D E F G H J L W

EHE

31
36

E1
E2

-VC

-PC

-VE

-PE

-VF

6.06

1.05

7.76

6.42

2.28

0.67

9.49

10.95

3.15

11.18

5.75

EHE

46

E1
E2

-VC

-PC

-VE

-PE

-VF

6.06

1.14

7.83

6.42

2.28

0.67

9.86

11.34

2.80

11.25

5.75

EHE

56

E1
E2

-VC

-PC

-VE

-PE

-VF

6.06

1.42

8.13

6.42

2.28

0.67

10.10

11.57

2.38

11.55

5.75

EHE

56

E1
E2

-VM 6.06

1.42

8.13

6.42

2.28

0.67

10.10

11.57

2.38

11.55

5.75

Mounting Dimensions

R S T

X

EHE all variations

5.20

4.50

1.00

0.28

L

C

E

A

B

H

G

D

J

W

F

R

X

S T

X

S

R

C

L

4

FC and HV Models

Model

A B C D E F H J L

W

EHE

31
36

E1
E2

-FC

6.06

1.05

7.76

6.42

0.65

0.67

9.69

3.15

9.53

5.75

EHE

46

E1
E2

-FC

6.06

1.14

7.83

6.42

0.75

0.67

10.00

2.80

9.72

5.75

EHE

56

E1
E2

-FC

6.06

1.42

8.13

6.42

0.85

0.67

10.45

2.38

10.12

5.75

EHE

36/46

E1
E2

-HV

6.06

1.05

7.80

6.42

0.70

0.67

9.69

2.95

9.60

5.75

Mounting Dimensions

R S T

X

EHE all variations

5.20

4.50

1.00

0.28

All dimensions in inches

OUT

L

C

E

A

B

IN

J

D

H

W

F

T

S

R

XX

C

L

S

R

5

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 to arrange for replacement.

CAUTION

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 fittings before attaching tubing.

Head bolts may have loosened during storage or shipment. Be sure to check and tighten to 19 lb-in of
torque, as necessary.

The electronics within the pump can be damaged by excessive surges in voltage. Do not install the
pump near high-power electrical equipment that generates high surge voltages. Avoid branch circuits
that also supply power to heavy or other equipment that could generate electrical interference. If
necessary, 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.

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.

2.2 Location

Choose a location for the pump that 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 elements. 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.)

6

Figure 1 Figure 2 Figure 3
Flooded Suction Shelf Mount Tank Mount
Suction Lift Suction Lift

If flooded 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).
For extremely gaseous liquids such as Sodium Hypochlorite or Hydrogen Peroxide, pulling from an
external manifold will significantly reduce gas bubbles to the suction side of the pump. This
installation will typically solve most priming issues associated with these gaseous liquids. See Figure
4 for reference.

Figure 4

Flooded Suction for Gaseous Liquids

Sodium

Hypochlorite

Storage Tank

7

The EH-HV Series pumps require a flooded suction or pre-primed condition before operation. Flooded
suction (mounting the pump below the level of liquid in the supply tank) is recommended for proper
operation of high viscosity pumps. (See Figure 1) These pumps are not designed to be self-priming.

The pump is supplied with ½” tube or ½” NPT male suction and discharge connections depending on model.
Mount the pump close to the supply tank and arrange the suction piping to be as short and straight as possible.
Avoid piping installations where air may become trapped in the suction piping.

Figure 5

2.3 Supply Tubing

The supply tubing run should be as short as possible. For flooded 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 fitting. For suction lift
applications, install a foot valve on one end of suction tubing and 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 rigid pipe will
help to keep tubing straight (see Figure 3). Total vertical suction lift should be no more than 5ft.
(1.5m).

Attach tubing as shown in Figure 5. First slide the coupling nut, small end first, onto the tubing.
Then slide on the clamp ring so that the rounded edges face the end of the tubing. Next push the
tubing onto the tubing adapter fitting. (Tips: Place tubing adapter fitting on a flat surface such as a
table top and press tubing down on top of it all the way to the lip of the tubing adapter fitting. 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
flare out more easily. Slide clamp ring down until it tightens over the adapter fitting. Then slide
coupling nut down as far as it will go. Insert this arrangement into the suction valve housing. With
one hand holding tubing and applying slight downward pressure, tighten the coupling nut until secure.

SUPPLY

TANK

TO POINT

OF

APPLICATION

VALVE

Calibration

Column

8

WARNING: All fittings and coupling nuts should be tightened by hand. If necessary, small pliers
may be used to make it snug. DO NOT use excessive force or large wrenches.

Figure 6 Tubing Connections

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 bends or kinks in the tubing and
protect the tubing from sharp edges that could chafe or cut it. If applicable, install the injection valve

in 1/2” NPT thread at the injection point and connect the discharge tubing to the injection valve.

Attach the tubing as described above in Section 2.3, Figure 5.

Note: Most pump models have an air vent valve with two connections on the discharge side of the
pump head. The connection marked 'OUT' is the discharge connection plumbed to the injection point.
The connection marked 'AIR' is the vent connection and tubing should be routed from this point back
to the chemical solution (supply) tank or drum. Refer to Section 1.4 drawing.

2.5 Installing Injection Check Valve

A fitting or tee with 1/2” NPTF threads and sufficient depth should be used to install the injection
valve assembly. If required, trim off an amount of the extension tip until it fits your fitting or tee (see
Figure 7). Attach the supplied tubing to the compression end: cut the tubing square, slide on the
coupling nut, push the tubing to the bottom of the cone (use warm water to soften tubing as
necessary), and hand tighten coupling nut.

The position of the injection check 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/replace the spring as needed.

CAUTION: Some chemicals may have reactions as they are injected into the main flow (ie. sulfuric
acid may react with water causing excess heat). If that chemical is heavier than water, mount the
injection valve as close as possible to vertical, injecting into the bottom of the pipe. This will keep
the injection nozzle facing up and keep the heavier chemistry from draining into the pipe causing
adverse reactions within the injection valve and pipe.

In addition to preventing backflow from pressurized lines, the injection valve will provide a limited
amount of backpressure when pumping into open atmosphere type applications. However, the
backpressure by the injection check valve is very low and can vary. Metering pump output is rated at

TUBING

ADAPTER

CLAMP

RING

COUPLING

NUT

Rounded edge
against tubing