Pentair Myers MSKV50 User manual

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INSTALLATION AND
OPERATION MANUAL
MY880 (3/1/21) ©2021 Pentair. All Rights Reserved.
SUBMERSIBLE SEWAGE EJECTOR PUMP
MSKV50

TABLE OF CONTENTS
General Safety ...................................................................................................................................................................................... 3
Installation............................................................................................................................................................................................4
Maintenance And Service...................................................................................................................................................................... 5
Parts List .............................................................................................................................................................................................. 7
Warranty............................................................................................................................................................................................... 8

3
MY880 (03-01-21)
GENERAL SAFETY
IMPORTANT SAFETY INSTRUCTIONS
This manual contains important instructions that should be followed
during installation, operation, and maintenance of the product.
This is the safety alert symbol. When you see this symbol on your
pump or in this manual, look for one of the following signal words and
be alert to the potential for personal injury!
indicates a hazard which, if not avoided, will result in
death or serious injury.
indicates a hazard which, if not avoided, can result in
death or serious injury.
indicates a hazard which, if not avoided, can or may
result in minor or moderate injury.
NOTICE: addresses practices not related to personal injury.
Carefully read and follow all safety instructions in this manual and
on pumps. Keep safety labels in good condition. Replace missing or
damaged safety labels.
Battery acid is corrosive. Do not spill on skin, clothing,
or battery charger. Wear eye and head protection when working with
battery. Connect and disconnect DC output terminals only after
removing the charger from the AC outlet. Never allow the DC terminals
to touch each other.
Hazardous Voltage. Can cause severe or fatal
electrical shock. Do not plug in or unplug battery charger while
standing on a wet floor or in water. Be sure one hand is free when
plugging in or unplugging charger. If basement floor is wet, disconnect
power to basement before walking on floor. If shut-off box is in
basement, call electric company or hydro authority to shut-off service
to house, or call your local fire department for instructions. Remove
pump and repair or replace. Failure to follow this warning can result in
fatal electrical shock.
Risk of flooding. Do not run pump dry. To do so will
damage seals and can cause leaking and property damage.
Risk of electrical shock. Do not lift the pump by the
electrical cord; lift pump only by the discharge pipe, lifting ring or
handle on the pump. Lifting by the cord can damage the cord.
CALIFORNIA PROPOSITION 65 WARNING
This product and related accessories contain
chemicals known to the State of California to cause cancer, birth
defects or other reproductive harm.
GENERAL SAFETY
Thank you for purchasing your Myers® pump. To help ensure
years of trouble-free operation, please read the following
manual carefully.
BEFORE OPERATION
Read the following instructions carefully. Reasonable care and
safe methods should be practiced. Check local codes and
requirements before installation.
Attention: This manual contains important information for the
safe use of this product. Read this manual completely before
using this product and refer to it often for continued safe
product use. DO NOT THROW AWAY OR LOSE THIS MANUAL.
Keep it in a safe place so that you may refer to it often.
Warning: Before handling these pumps and controls, always
disconnect the power first. Do not smoke or use sparkable
electrical devices or flames in a septic (gaseous) or possible
septic sump.
PUMP WARNING
To reduce risk of electrical shock:
1. Risk of Electrical Shock: This pump has not been
investigated for use in swimming pool areas.
2. Risk of Electrical Shock: Connect only to a properly
grounded receptacle. Septic tank to be vented in
accordance with local plumbing codes.
Do not smoke or use sparkable electrical devices or flame
in a septic (gaseous) or possible septic sump.
If a septic sump condition exists and if entry into sump is
necessary, then (1) provide proper safety precautions per
OSHA requirements and (2) do not enter sump until these
precautions are strictly adhered to.
Do not install pump in location classified as hazardous per
N.E.C., ANSI/NFPA 70 - 2001.

4MY880 (03-01-21)
These important instructions must be followed for satisfactory
performance of your pump. Before installation, check your
local electrical and plumbing codes.
1. Provide proper sump size to allow the pump to operate
without restrictions. A two- to five-minute run
time is recommended. Also, minimum 24" diameter
recommended.
2. Make sure sump is free of string, cloth, nails, gravel, etc.
before installing pump.
3. Do not set pump directly on the bottom of sump pit if it is
not solid. Raise the pump by placing bricks or concrete
blocks underneath it.
4. Use steel or plastic pipe for all connecting lines between
pump and sewer outlet.
NOTE: Some city regulations do not allow installing a
pump with plastic pipe. Check local regulations.
5. In applications where the pump may sit idle for months at a
time, it is recommended that the pump(s) be cycled every
month to ensure the pumping system is working
properly when needed.
6. A check valve should be installed in discharge pipe, at
least 12" above the discharge outlet of the pump.
7. An audible alarm system for high water conditions should
be installed in every pump for greater protection.
NOTE: Alarm is for indoor use only. Contact your Myers
distributor for other panel applications.
WARNING: When using the automatic diaphragm switch
the vent tube in the plug must be clear of obstructions.
Do not bend cord. This will cause a crimp in the vent tube
and switch failure will occur. Pump should be plugged into
a single outlet, where vent tube can “breathe.” Blocking
tube or bending cord will void the warranty.
8. Connect to power source using 3-prong grounded AC
receptacle. Do not remove ground pin from electrical plug.
Do not use an extension cord.
9. For proper automatic operation (MSKV50AD and
MSKV50AW) make sure the pump power cord is plugged
into the back of the piggyback receptacle on the float
switch cord.
10. Use pump partially or completely submerged for pumping
(temperature to 140° F). The MSKV50 will pump solid
materials up to 2" (spherical) in diameter.
INSTALLATION

MSKV50 Typical Installation

5
MY880 (03-01-21)
PUMP SERVICING
Servicing should be performed only by knowledgeable pump
service contractors or authorized service stations.
1. Remove pump from sump. Before removing pump from
sump pit for repair, check if the trouble could simply be
a blown fuse, tripped circuit breaker, or a power cord not
completely inserted into the receptacle.
2. Check diaphragm switch. If the unit is being operated by
the automatic diaphragm switch, unplug the pump from
the piggyback receptacle and plug the pump directly
into the power source. If the pump starts each time it is
plugged directly into the receptacle and does not start
each time when plugged into the piggyback switch with
the diaphragm switch pressed into a start position,
replace the complete piggyback switch assembly and
retest with new assembly.
3. Check for impeller blockage. Disconnect pump and
switch from power source. Check for an obstruction in
the impeller cavity by laying the pump on its side and
inserting a screwdriver into impeller. Impeller should turn
freely. If impeller is stuck, then turn the pump on its side,
DRAIN THE OIL through the oil fill plug on top of the pump.
Drain oil into a clean, dry container. A milky appearance
to the oil indicates that water has entered through either
worn out or damaged seals (7) or seal ring. Remove the 4
screws (6) to remove the volute (9). If the impeller (10) does
not rotate freely, clear the impeller and cavity walls before
reassembling the base. Repeat Step 2.
4. Check power cord. If the above tests have not resolved
the problem, it may be in the electrical components of the
pump. Starting with the power cord (2), inspect for cuts or
nicks in the insulation. If the cord is damaged – replace it!
5. Remove the motor cover. Use a screwdriver to pry the
motor cover (3) from the seal plate (8) at the fastening ears,
being careful not to cut the seal ring with the screwdriver
or crack the motor cover. Lift the motor cover until it
clears the stator (4).
6. Check for short. Disconnect the stator leads from the
connector. Use an ohmmeter to check the continuity of
the stator. If stator fails to pass the continuity test, it must
be replaced.
Ground check. Set ohmmeter scale pointer to R X 100K
scale and check meter by putting both meter leads
together and adjusting the needle knob until meter
reads zero. If meter cannot be adjusted to zero it will
indicate that batteries in meter must be replaced.
Always make this test with the meter when scale pointer is
set to a new scale before making any checks on motor.
Now connect one meter lead to one blade terminal of
stator and touch other meter lead to motor stator shell
(4). If needle reads below 5 (500,000 ohms) stator must
be dried out before reusing. To dry out, bake in 220° oven
for 4 hours. Recheck after motor cools. If motor is new or
thoroughly dry, needle of ohmmeter will not move on the
ground test. This indicates a reading of 50 megohms or
higher. One megohm is one million ohms.
When making the ground test, if the needle goes clear to
zero the motor probably has a wire touching the stator at
some point and the stator will have to be replaced.
Winding resistance test. If motor shows a satisfactory
ground test, then the winding resistance must be
checked. Use ohmmeter with scale pointer set on R X 1
scale. On this scale meter reads directly on ohms. Always
check the meter with leads together as described above
under ground test before making a reading of the winding.
Connect one meter lead to each of the black terminal
leads. Meter should read about 1.35 ohms. This is the
resistance of the main winding for a 115 volt stator. This
reading for a 230 volt stator should be about 6.22 ohms.
Now remove the capacitor and connect one meter lead to
each of the brown wire terminals. The meter should read
about 11.35 ohms for a 115 volt stator. For a 230 volt stator
this reading should be 32.4 ohms. This is the resistance of
the start winding.
7. Remove the stator. To remove the stator, remove the four
hex head screws and disconnect the brown capacitor
leads from the capacitor and remove the stator plate with
the capacitor. Lift the stator off the seal plate (8) and set
aside.
8. Remove the impeller. To remove the impeller (10), hold
the motorshaft (5) with a screwdriver at the center of
the impeller and tap the impeller with a plastic or rubber
mallet so as to turn the impeller counterclockwise.
MAINTENANCE AND SERVICE
CAPACITY GALLONS PER MINUTE
TOTAL HEAD IN METERS
TOTAL HEAD IN FEET
CAPACITY LITERS PER MINUTE
40
30
20
10
0
0 180150120906030
MSKV50
6187 0716

6MY880 (03-01-21)
9. Check the seal. Remove the rotating portion of seal
(6) from shaft by inserting a screwdriver under the edge
of the seal and lifting it off. Inspect the seal face for any
nicks or an uneven seating of seal face. If any are present,
replace the seal. (See Step 14.)Remove rotor and shaft.
Tap the rotor shaft (5) at the impeller end of the shaft with
a plastic mallet to remove the rotor and shaft. Inspect the
bearings. If they do not rotate freely and smoothly, they
should be replaced.
10. Remove rotor and shaft. Tap the rotor shaft (5) at the
impeller end of the shaft with a plastic mallet to remove the
rotor and shaft. Inspect the bearings. If they do not rotate
freely and smoothly, they should be replaced.
11. Remove seal. Remove the old stationary portion of the seal
(7) from the seal plate by inserting a screwdriver into the
seal housing of the seal plate from the top of the case and
tapping lightly with a hammer. Clean the seal area of the
seal plate (8) with a clean cloth.
12. Reinstall the rotor and shaft assembly. Push on outer face
to seat bearing in seal plate.
13. Reinstall seal. Apply a good lubricant to the new
stationary portion of the seal (7) and press into the seal
plate. Coat the new rotating portion of seal with
lubricant and press into place on the rotor shaft with
the rubber ring facing
the impeller.
14. Reinstall impeller. Add a drop of Loctite 222 to the shaft
and screw the impeller on hand tight. The impeller will
force the rotating portion of seal into position.
15. Replace seal ring. Remove the old square seal ring from
the seal plate and stretch on a new ring coated with O-ring
lube. Do not roll the ring onto the seal plate or improper
seating and water leakage into the motor housing will
result.
16. Reinstall the stator. Place the stator (4) in the seal plate (8)
so the stator bolt holes line up. Lay the stator plate on the
stator (4) and line up with stator bolt holes. Put in the stator
bolts and tighten evenly to prevent cocking of the stator.
Connect the capacitor to the capacitor leads. Push the
connectors of the two black stator leads onto the power
cord spade terminals.
17. Reassemble pump. Replace the motor cover (3) on the
seal plate (8). Place the assembly on the volute (9). Insert
the four cap screws (6) through the motor housing ears,
into the tapped holes in the volute. Tighten them evenly to
prevent cocking the motor housing and causing an uneven
seal on the seal ring.
18. Oil. Fill the motor cap with high grade transformer oil just
covering over stator end cap (.45 gallon).
19. Do not fill the motor housing completely – allow airspace
for oil expansion. Make sure the stator and capacitor are
fully immersed. You will have to peer through the oil plug
hole to be sure of the correct oil level.
MAINTENANCE AND SERVICE
Model Number Motor
HP
Feet
(meters) Volts Phase Max Load Amps
Individual Branch Circuit
Required (Amps)
Discharge Adapter
Size (inches)
Switch Setting in inches (mm)
On Off
MSKV50AD110 1/2 10 (3.1) 115 112 15 212.25 (31.1) 3.75 (9.5)
MSKV50AD120 1/2 20 (6.1) 115 112 15 212.25 (31.1) 3.75 (9.5)
MSKV50AW110 1/2 10 (3.1) 115 112 15 214 (35.6) 7.5 (19.1)
MSKV50AW120 1/2 20 (6.1) 115 112 15 214 (35.6) 7.5 (19.1)
MSKV50M110 1/2 10 (3.1) 115 112 15 2 - -
MSKV50M120 1/2 20 (6.1) 115 112 15 2 - -
MSKV50M220 1/2 20 (6.1) 230 1 6 10 2 - -

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MY880 (03-01-21)
1
2
PARTS LIST
MODEL – MSKV50
Key
No. Description Quantity MSKV50AD110 MSKV50AD120 MSKV50AW110 MSKV50AW120 MSKV50M110 MSKV50M120 MSKV50M220
1 Cord 115V 10' (3.1m) 1 146230101 146230101 146230101
1 Cord 115V 20' (6.1m) 1 146230201 146230201 146230201
1 Cord 230V 20' (6.1m) 1 146232201
2Piggyback Tethered Float
Switch 115V 10' (3.1m) 1145951101
2Piggyback Tethered Float
Switch 115V 20' (6.1m) 1145951201
3 115V 10’ Diaphragm Switch 1 DPS81 10
3 115V 20’ Diaphragm Switch 1 DPS81 20

WARRANTY
Limited Warranty
Myers®warrants to the original consumer purchaser (“Purchaser” or “You”) of the products listed below, that they
will be free from defects in material and workmanship for the Warranty Period shown below.
Product Warranty Period
whichever occurs first:
Jet pumps, small centrifugal pumps, submersible
pumps and relatedaccessories
12 months from date of original installation,
or 18 months from date of manufacture
Fibrewound Tanks 5 years from date of original installation
Steel Pressure Tanks 5 years from date of original installation
Sump/Sewage/Effluent/Utility/Battery Backup Products 36 months from date of manufacture
Wastewater Solids Handling Pumps 12 months from date of shipment from factory
or 18 months from date of manufacture
Our warranty applies only where such products are used in compliance with the requirements of the applicable
product catalog and/or manuals. For additional information, please refer to the applicable standard limited
warranty featured in the product manual.
Our warranty will not apply to any product that, in our sole judgment, has been subject to negligence,
misapplication, improper installation, or improper maintenance. Without limiting the foregoing, operating a
three phase motor with single phase power through a phase converter will void the warranty. Note also that
three phase motors must be protected by three-leg, ambient compensated, extra-quick trip overload relays of
the recommended size or the warranty is void.
Your only remedy, and MYERS’s only duty, is that MYERS repair or replace defective products (at MYERS’s choice).
You must pay all labor and shipping charges associated with this warranty and must request warranty service
through the installing dealer as soon as a problem is discovered. No request for service will be accepted if
received after the Warranty Period has expired. This warranty is not transferable.
MYERS SHALL NOT BE LIABLE FOR ANY CONSEQUENTIAL, INCIDENTAL, OR CONTINGENT DAMAGES
WHATSOEVER.
THE FOREGOING LIMITED WARRANTIES ARE EXCLUSIVE AND IN LIEU OF ALL OTHER EXPRESS AND IMPLIED
WARRANTIES, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE. THE FOREGOING LIMITED WARRANTIES SHALL NOT EXTEND BEYOND THE
DURATION PROVIDED HEREIN.
Some states do not allow the exclusion or limitation of incidental or consequential damages or limitations on the
duration of an implied warranty, so the above limitations or exclusions may not apply to You. This warranty gives
You specific legal rights and You may also have other rights which vary from state to state.
This Limited Warranty is effective January 1, 2021 and replaces all undated warranties and warranties dated
before January 1, 2021.
PENTAIR MYERS
293 Wright Street, Delavan, WI 53115
Phone: [phone] • Fax: [phone] • www.femyers.com
In Canada: 490 Pinebush Road, Unit 4, Cambridge, Ontario N1T 0A5
Phone: [phone] • Fax: [phone]
US: 293 WRIGHT ST
DELAVAN, WI 53115
Phone: [phone]
Fax: [phone]
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