Why Is My Water Pressure Low in Winter?

Most winter water pressure drops in Surrey are caused by partially frozen pipes, sediment buildup in fixtures, or a failing pressure-reducing valve. When temperatures dip below freezing, the water inside your lines can begin to crystallize. This restricts flow before the pipe actually bursts.

Over our 20 years fixing plumbing in Surrey, we have seen that a sudden drop in pressure is usually a warning sign. Catching it now can prevent a major flood when the weather eventually warms up.

What You Will Learn

Here is exactly what we will cover to help you restore your home’s water flow:

• Cleaning Your Aerators: How simple debris from older city pipes can clog your faucets.
• Checking the Main Shut-off Valve: Making sure your primary water source is fully open.
• Inspecting the Pressure Reducing Valve (PRV): Identifying when this critical component fails due to cold stress.
• Safely Thawing Partially Frozen Lines: Using gentle heat to restore flow without damaging your plumbing.
• Flushing Your Water Heater: Preventing sediment from blocking your hot water supply during peak winter demand.

How Do I Clean My Faucet Aerators?

Why It Matters

Winter weather often causes shifts in the soil that can rattle older pipes. This sends small bits of sediment or mineral scale toward your fixtures. This debris often gets trapped in the small mesh screen at the tip of your faucet, which is the aerator.

How to Fix It

You can usually fix this in under five minutes:

• Unscrew the aerator from the tip of the faucet by hand or with a pair of pliers.
• Rinse the screen under water to remove any visible grit or sand.
• Soak the parts in white vinegar for a few minutes if you notice heavy mineral buildup.
• Reassemble the fixture and test the flow.

If the pressure is back to normal, you have solved the problem with a simple, no-cost fix.

Is My Main Water Valve Fully Open?

The Common Culprit

Sometimes the simplest solution is the one we overlook. Your main water shut-off valve can be bumped or partially closed during winter cleaning or while moving holiday decorations in the garage.

What to Check

Locate your main valve and ensure the handle is turned fully to the “on” position. In many Surrey homes, this is a gate valve (a round wheel) or a ball valve (a lever handle). Even a quarter-turn toward the “off” position can significantly reduce the pressure throughout your entire house.

Is My Pressure Reducing Valve (PRV) Failing?

Cold Weather Stress

The PRV is a bell-shaped brass component that sits on your main water line. It is responsible for slowing down the high-pressure city water so it does not damage your plumbing. Inside the PRV is a rubber diaphragm that can become brittle and fail during extreme cold snaps.

Warning Signs

If your pressure has dropped suddenly across every fixture in the house, the PRV is likely the issue. You might also hear a humming or vibrating sound coming from your pipes when you turn on a tap. Replacing a PRV is a standard job for our team, and it is much safer than letting your pressure fluctuate.

How to Safely Thaw Partially Frozen Pipes

The Warning Sign

If you turn on a tap and only a trickle comes out, but the pressure eventually improves as the day warms up, you likely have a partially frozen pipe. This often happens in Surrey homes with pipes located along exterior walls or in unheated crawlspaces.

The Safe DIY Fix

Never use an open flame or a torch to thaw a pipe. This is a massive fire risk. Instead, follow these safe steps:

• Open the faucet slightly so water can flow as the ice melts.
• Use a hairdryer or a space heater to gently warm the suspected area.
• Wrap the pipe in towels soaked in warm water.

Why Is My Hot Water Pressure Low?

Sediment and Winter Demand

If your cold water pressure is fine but your hot water is a crawl, the issue is inside your water heater. During winter, your tank works much harder, which can stir up sediment at the bottom. This grit can get sucked into the hot water exit pipe, blocking the flow to your showers and sinks.

The Solution

Flushing your tank can often clear these blockages:

• Attach a garden hose to the drain valve at the bottom of the heater.
• Run the hose to a floor drain or outside.
• Let it run until the water is clear of any “snow” or white flakes, which are actually calcium deposits.

When to Call a Pro?

While many pressure issues are easy to troubleshoot, some situations require an expert eye to prevent property damage:

• The Pressure Drops to Zero: If you lose water entirely, you likely have a complete freeze or a burst main line. Turn off your water immediately and call us.
• Visible Leaks: If you see water pooling near your foundation or dripping from a ceiling, do not attempt a DIY fix.
• Failing PRV: Replacing a pressure-reducing valve involves cutting into your main line. This is a job best left to a licensed professional.
• Strange Noises: If your pipes are banging or whistling, it usually indicates a serious pressure imbalance that could lead to a burst.

Bottom Line

Low water pressure in the winter is usually your home’s way of telling you something is wrong before a major pipe failure happens. Taking a few minutes to check your aerators and valves can save you from a very expensive emergency call later this season.

If you have tried these fixes and your shower still feels like a drizzle, Mark and the team at South Surrey Plumbing are ready to help.

Give us a call at (604) 897-4989 or email us here.