Why Does My Shower Keep Going Hot and Cold?

Young woman reacting in shock to hot or cold shower water

If you’re enjoying a steamy hot shower when out of nowhere the water turns freezing cold or suddenly goes scorching hot, you may be wondering why this is and how to fix it. If you’re keen to solve these fluctuating temperatures in the water you use around the home, it may be time to have a closer look at your plumbing system. Read on for some helpful ways to understand these erratic alterations in temperature and identify the causes of water temperature fluctuations in your home plumbing that are ruining your shower time.

Examine your water heater’s size and type

If you’ve experienced unexpected hot water running, it may be a sign that your water heater is underpowered and out of date. Water heaters are specifically designed in a wide variety of sizes and types to suit different amounts of water. Models will typically be either electric or gas.

Water temperature

The first step is to isolate the issue by testing the water temperature in a single shower. Turn off all other appliances that consume water in your home. If the water temperature in your shower remains consistent in these conditions, the problem will likely involve other factors. Now turn on your second shower if you have one and test the water temperature with both units running. If you notice temperature fluctuations, the problem may be that your water tank needs to be larger.

Inspecting your water heater

Never attempt to dismantle a water heater unless you have professional plumbing experience. Instead, perform a visual inspection of your water heater to identify any problems and study your water heater’s user manual for maintenance safety instructions.

Checking your emergency thermostat

The emergency thermostat is critical. It’s designed to shut off your water tank to prevent dangerous situations from occurring. If your automatic shut-off is not activated, your unit will keep heating your water. If this is the case, contacting a professional plumber to repair your water heater is advised.

Resetting your thermostat

Modern water heaters are fitted with safety features designed to alert you when your water temperatures have become dangerous. If you find this feature has tripped, resetting the thermostat is necessary. There could be a bigger problem if your thermostat is tripping often. However, a damaged thermostat isn’t usually the cause of fluctuating temperatures in your shower.

A more common problem is a faulty temperature regulator. When the regulator isn’t working, the water temperature will reach a specific threshold, and the unit will cease heating.

Gas water heaters

When you have a gas water heater, run through the following process. Check and see if your pilot light is still on, and if it’s off, try to relight it. Turn the gas valve off and then wait for a few minutes before turning the valve back to the pilot position. Use the ignition switch to ignite your pilot light. When your pilot light is back on, you can set the valve back once more to its standard position.

Moisture in basements can also cause problems. A basement that has become flooded or simply damp can be the cause of a pilot light going off. If you find your pilot light keeps going off, this can be a serious problem requiring professional attention.

Electric water heaters

However, if you have an electric water heater, first check out your circuit breakers. If this is the problem, you can restart your water heater by flipping the dedicated breaker back into place. If you find that your heater is constantly tripping this circuit breaker, you could have a more serious issue on your hand, so consult a professional electrician immediately.

How much water are you using in your shower?

An average shower will use somewhere around two gallons per minute. If you have a large family household with several showers, you’ll obviously end up using more water.

Custom spray heads and modern shower heads designed to deliver high-volume will rapidly deplete small size water heaters. You will often find a label on the side of your water heating unit indicating the size of the tank, how much water it can hold and an estimate of how much hot water time it can provide.

Water temperatures that fluctuate when you least expect them can be extremely dangerous and cause injuries. Hot water that is scalding can damage your skin and give younger children serious burns when an unpredictable surge issues from the showerhead unexpectedly.

If you have multiple showers around your home and your water heater’s size can’t cope with the demand necessary to heat them all, contact a professional and arrange an upgrade. A water heater that is not the correct size can cause damage to your skin along with the plumbing system fitted in your home.

Checking your pressure balancing valve

When you’re in the shower and notice a change in temperature, pay close attention. Ask another household member to flush a toilet or turn on the dishwater. If the water temperature in the shower fluctuates, then the pressure-balancing valve could be the cause of your problem.

Depending on the water flow within your home’s plumbing system, the dedicated pressure-balancing valves will close or open. If hot or cold-water levels lower, a pressure valve that is damaged could potentially cause a drop in your water pressure. This fall in pressure will then send either freezing cold or scalding hot straight to your shower head. The good news is that pressure balance valves can be replaced, but the work will require a professional plumber to tackle the task.

Do you require a professional to fix your fluctuating shower water temperatures?

If you’re experiencing temperature changes in your bathroom, don’t settle for an icy shower. Check all your home plumbing and water units around the house and attempt to identify what’s causing your shower problems.

For any work required that you can’t handle by yourself, always enlist the help of an expert plumber with the tools and skills and experience to solve your problems.

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