The last weekend at the cottage usually goes by quickly. The dock comes in, the boat gets covered, and the water lines get drained quickly before the drive home. In that rush, it’s easy to forget the filter housings in the pump room, and that small gap can mean cracked equipment when you return in May next year.
A water filtration system at a seasonal property needs its own fall shutdown routine. The pump, pressure tank, sediment and carbon housings, and UV unit each hold water after the main lines are drained. Empty and check each one before the cottage sits unheated for the winter.
Here is why this step deserves a little more time. Most filter housings and UV chambers are not built to survive freezing while full. A cracked housing bowl or split quartz sleeve is a common spring discovery, and replacement parts aren’t always in stock when every cottage owner on the lake needs them at once.
Why Frozen Water Damages Filter Housings and UV Systems
Water goes through volumetric expansion as it freezes, growing by about nine percent in volume. Inside a sealed plastic housing or a glass quartz sleeve, that extra volume has nowhere to go. The pressure can split a housing bowl, crack a sleeve, or break the fittings on the head of a filter.
Freezing is only one concern. A wet cartridge left in a dark housing for six months gives bacteria a place to grow, and they form a slimy layer called biofilm on the media and inside the bowl. When the system starts again in spring, that growth can release into the lines and affect the taste and odour of the water.
So the goal in fall is simple. Remove the water and remove the used media.
Step-by-Step Fall Shutdown for Cottage Filters
Let’s break it down in the order most cottage owners follow:
- Turn off the power to the pump and the UV system at the breaker or plug.
- Open a low tap and drain the pressure tank and main lines.
- Shut the valves on either side of the filter housings, then press the pressure relief button on each housing head.
- Unscrew each bowl, dump the water, and throw out the old sediment and carbon cartridges.
- Rinse the bowls, let them dry, and store them upside down or loosely threaded on the head.
- Set the O-rings aside in a bag so they do not dry out or go missing.
Some owners prefer to reinstall the empty bowls hand-tight so dust and mice stay out. Others leave them off. Either approach works, as long as no water stays inside.
Draining and Storing a UV Disinfection System Over Winter
The UV unit needs more care than the cartridge housings. Once the power is off and the lamp has cooled, drain the UV chamber through its drain port or by loosening the inlet fitting. Then remove the lamp and the quartz sleeve.
The sleeve is fragile, so handle it with clean cotton gloves and wrap it in a soft cloth. Store the lamp and sleeve indoors, perhaps in a box in a heated closet at home. A UV lamp usually has a rated life of about 9,000 hours, or close to one year of steady use. If the lamp ran most of the season, spring is a reasonable time to replace it, although some owners change it every second season based on hours used.
What about the controller? Most UV controllers do not hold water, but cold and damp can still affect the electronics. When possible, take it home.
Spring Startup and Replacement Parts to Order in Advance
Spring startup is close to the shutdown in reverse. Reinstall the sleeve and lamp, fit new cartridges, check the O-rings, and close the drains. Restore the water and look for leaks before turning on the UV system.
A few items are worth ordering over the winter so they are ready before the first trip up:
- Sediment and carbon cartridges in the correct size, such as 10-inch or 20-inch
- A replacement UV lamp matched to the model number of the system
- Spare O-rings and silicone lubricant for the housings
- A new quartz sleeve if the old one shows scratches or staining
Run the water for several minutes after startup to flush the lines. A shock chlorination of the plumbing and a bacteria test after opening can confirm the water is safe to drink, especially for lake-fed systems.
Next Steps Before Closing the Cottage This Fall
Write down the model number of each housing and the UV system, plus the cartridge sizes and micron ratings. Take a photo of the pump room setup before taking anything apart. Those notes make ordering parts easier and help a water treatment specialist answer questions about your system.
You can order cartridges, UV lamps, quartz sleeves, O-rings, and complete filtration systems online, and we can ship them to cottage and rural addresses across Canada.
