Preparing a submersible pump for winter: checklist for portable and permanent pumps
David MeijerShare
Quick answer: portable pump: flush it with clean water, check the cable and strainer, let the pump and hoses drain completely and store it frost-free and upright. Permanent pump in a sump or basement: simply leave it in place, but test the float switch and alarm before winter and make sure the discharge pipe cannot freeze. Get your emergency kit ready for the autumn storms.
Why prepare for winter?
Water expands when it freezes. If water is left behind in a pump, a non-return valve or a hose, the pump housing can crack, the seal can be damaged or the hose can burst. You only notice in spring, when the pump won't start or starts leaking. On top of that, a pump that sits dirty in a shed for months will be seized when you need it again: dried sludge in the impeller is just like cement.
Winter is also the season of autumn storms and flooding from prolonged rain. A pump you need at that moment has to work straight away.
Checklist for a portable pump
| Step | What you do |
|---|---|
| 1. Flush | Let the pump run clean water for a few minutes, in a bucket or barrel. This flushes sand and sludge out of the impeller. |
| 2. Inspect | Check the cable for cracks and kinks, and the strainer and impeller for wear or blockages. Replace damaged parts now, not when the water is already rising. |
| 3. Drain | Tilt the pump or turn it upside down so that all the water runs out. Let the hoses drain completely as well. |
| 4. Store | Upright, dry and frost-free. Do not hang it by the cable: that damages the cable entry. |
| 5. Couplings | Clean the rubber seals of Storz and GEKA couplings and apply a thin layer of silicone grease. This stops the rubber from drying out. |
| 6. Float switch | Check that the float switch moves freely and has not dried up or become caked in place. |
Permanent pump in a sump or basement
A pump that is permanently installed in a sump simply stays in place: under water it will not freeze. But winter is the right time to test it, precisely because it has to work hardest during the wet months.
- Test the float switch. Pour a few buckets of water into the sump or lift the float switch, and check that the pump switches on and off again. A float switch stuck against the wall is the most common reason a basement floods anyway.
- Test the alarm. If you have a high-water alarm, let it go off once. No alarm? Consider getting one: see the alarm systems.
- Discharge pipe and non-return valve. If the discharge pipe runs outdoors or through an unheated space, make sure it can drain or insulate it. A frozen pipe means the pump is pumping against a closed tap.
- Clean the sump. Remove leaves, sand and sludge from the sump. A clean sump means a pump that doesn't clog.
- Flat suction pump with sensor or electrodes: clean the electrodes, otherwise the pump will switch unreliably.
Garden and pond pumps
A garden pump or domestic water booster that stands outdoors or in an unheated shed must be drained completely. Unscrew the drain plug, let the pressure tank and pipes drain and store the pump frost-free. A pond pump in deep water can stay in place, but take it out if the pond is shallow or can freeze over.
Ready for the wet months
Put your pump, hose and couplings together in a fixed place now, so you don't have to search for them when flooding strikes. If you don't have a pump or want a spare, you will find ready-made kits among our emergency kits. What to do once the water is already rising is covered in flooding after heavy rain.
Parts worth replacing now
- Hoses with cracks or kinks
- Couplings with dried-out or cracked rubber seals
- A float switch that no longer switches reliably
- A non-return valve that leaks or sticks
Frequently asked questions
How do I prepare a submersible pump for winter?
Flush it with clean water, check the cable and strainer, let the pump and hoses drain completely and store everything upright, dry and frost-free.
Can a submersible pump stay in the sump during winter?
Yes. Under water it will not freeze. Do test the float switch and the alarm, clean the sump and make sure the discharge pipe cannot freeze.
Can I hang a pump by its cable?
No. That pulls on the cable entry and can let water leak into the motor there. Use the handle or a chain.
Why is my pump seized in spring?
Usually sludge has dried in the impeller. Flushing the pump with clean water before storing it prevents this.
Need your pump again and not sure it still works properly?
Send us the model and a photo of the rating plate. We will tell you honestly whether a repair is worthwhile or whether a new pump is the wiser choice.
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