Why Does My Shower Only Have Hot Water? 6 Underlying Causes and How to Fix Them

No one likes a cold shower, but a shower that only has hot water is a problem, too. If you’re wondering why your shower only has hot water, most of these solutions are simple and DIYable. Understand what’s causing the problem and how to address it to avoid more serious issues, so you can get back to bathing in bliss.

1. Broken Shower Cartridge

A broken or faulty shower cartridge is the most likely reason for your shower delivering only hot water. The cartridge is the part of your shower that regulates the amount of hot and cold water, and it may only deliver one or the other if it’s damaged.

The Solution

You can replace your shower cartridge yourself if you’re comfortable with DIY plumbing work. Unscrew the faceplate around the handle, remove the clip that holds the cartridge in place with pliers or a vice grip, and then install a new cartridge. You can also hire a pro to get this done for an average of $150.

2. Shut Water Main 

The water main is the valve that allows water into your home when open and shuts it off entirely when closed. Even with the main shut, your fixtures can still get hot water that’s stored in the water heater until it runs out. Shutting the water main isn’t something you do on a normal basis, but if you recently had plumbing work done or DIYed a plumbing repair, this could be the issue.

The Solution

The solution is a simple one: Find your water main and make sure it’s open. It’s usually located in a utility closet in your basement, but it could be under a sink on your first floor if you have a slab foundation. In some cases, it’s located under your front yard.

For a ball valve, it’s open when the handle is parallel to the pipe. For a gate valve, it’s open when you turn the handle counterclockwise. To open a curb valve, you’ll need a plumber.

3. Mineral Buildup

Mineral build-up in the cold water supply line to your shower could also cause a partial or complete blockage, which means mostly or only hot water will come out. This could be the issue if you have older plumbing and hard water in your area, and it’s the most likely culprit if you notice that your showers are gradually getting hotter and hotter over time.

The Solution

For this repair, you’ll need to call a plumber to remove the corroded or blocked pipe and replace it. Installing a whole-home water softener can help prevent the problem from recurring.

4. Frozen Pipe

Just like with mineral buildup, ice inside your pipes can prevent cold water from making it to your shower. This could be the issue if you live in a particularly cold climate, especially if you have aging insulation and the bathroom is against an exterior wall. Cold water pipes are more likely to freeze than hot water pipes, so you could still be getting hot water to the shower if those haven’t frozen over.

The Solution

Always call a plumber to address frozen pipes. Expanding ice can lead to breaks and major water damage, so it’s best to have a pro help thaw them and replace them, if necessary.

5. Local Supply Line Valve Is Shut

Older homes sometimes have access panels in or around the shower that house local shut-off valves. Recent plumbing work may have involved shutting one or both valves, in which case you or your plumber may have forgotten to open the cold valve back up.

The Solution

Open your shower access panel and make sure the cold water valve is open. For gate valves, spin the handle counterclockwise. For ball valves, make sure the handle is parallel to the pipe.

6. Water Leak

In extreme cases, a water leak may be causing the issue if it occurs only on the cold water supply line. In this case, the cold water you call for could be draining behind your walls, leaving mostly hot water to come out of your shower. For a leak to cause hot-only showers, it would have to be severe, so you’d almost certainly notice the water damage before the uncomfortable showers.

The Solution

Shut the water main to prevent further water damage, and contact an emergency plumber right away to repair the leak.

When to Call a Pro

In most cases, a shower that only gets hot water is caused by a damaged cartridge, and you can replace this yourself for between $20 and $60. If you’re uncomfortable with plumbing work or don’t have experience, a professional plumber is the way to go, and the repair should take less than 20 minutes.

You can also check to make sure your water main and local supply lines are open, but call a professional if you can’t find your water main. Additionally, always defer to a certified plumber near you if you suspect that a frozen pipe, corrosion, or mineral buildup is to blame.