Winterizing Pump Systems

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Disconnect power to the pumping system before beginning any work.

Ensure that pump to be winterized cannot be accidentally energized during the process or after finishing the process. You may need a qualified, licensed electrician to do this. Tape any exposed leads from the motor and power supply and close any open electrical panels to protect them from the elements.
Remove exterior dirt, grime, or any substance that may trap moisture.
Exposed metal is subject to oxidation (rust). Prime the exterior surfaces and repaint them as necessary. Be sure to use lead and chromate-free paint. Ensure that the pump and motor identification tags are not painted. Be sure the motor vents are clear of debris of any kind.
Flush the suction and discharge piping systems.
Open the suction and discharge piping systems at both ends (at the pump and either the highest or lowest point of each system). Also, disconnect the pressure switch tube. Allow them to drain. A low-pressure (5 PSI), high-volume blower may be used to purge the system using air pressure. Wet/Dry Shop Vacuums may also be used for system drainage. The piping systems should be drained to below the freeze line. Any pressure or storage tanks attached to the piping systems above the freeze line should be drained as well. Repair any piping system leaks at this time.
Drain the pump housing.
Open an air-bleeding valve or remove a port plug on top of the pump housing. Remove the port plug closest to the bottom of the pump housing. This should allow the water to drain from the pump housing. Some pump models will not have drain port plugs. These types of pumps will require tipping the pump on its nose to drain off the accumulated water. Flush out the pump housing with clean, fresh water to clear out rust and debris, which may have accumulated inside. You will need to tip the pump on its nose to be sure of total drainage of the water.
“Dry” pump storage considerations.
Seal all open ports on the pump housing (and the motor if applicable) to keep out dust, dirt, insects, rodents, etc.
“Wet” pump storage considerations.
Do not use any anti-freeze solutions except propylene glycol or an approved equal. The propylene glycol or an approved equal should be non-toxic and not damage plastic components in the pump or piping systems. Follow instructions from the manufacturer to get the proper mix of water and anti-freeze (propylene glycol or an approved equal) for the rated temperature from which you need to protect the pump. Plug the ports of the pump except for the highest one. Pour in the anti-freeze (propylene glycol or an approved equal)/water mix until the pump housing is full. Plug the port you poured the mixture into.
Guard against corrosion.
Keep the unit clean and dry during the storage period. Shelter the pump from the elements. To avoid condensation and corrosion problems, do not wrap or seal pump tightly with plastic. Air must be allowed to circulate around the pump.
Rotate the motor shaft periodically during the storage period.
This action will prevent the internal components from binding together and keep the pump and motor parts properly lubricated. This will help prevent corrosion and oxidation (rust). This is particularly important for “dry” pump storage. Any further motor storage information should be obtained from the motor manufacturer.
Protect the pump fittings and accessories.
Place the pump fittings and accessories (pressure gauges, bolts, nuts, shims, wire nuts, elbows, nipples, etc.) in a heavy gauge plastic bag (or other container) and attach it to or store it with the pump.
Suction pipe protection advice.
If you are pumping from a shallow well (25 feet or less), lake, pond, reservoir, etc. you will want remove and drain all of the suction piping system to prevent freeze damage.