When only your sink has hot water but your shower, washing machine, or dishwasher doesn’t, it’s not just annoying—it’s a sign something’s wrong with your water heater, a home appliance that heats and stores water for multiple fixtures. Also known as a hot water tank, it’s the heart of your home’s hot water system. If it’s working fine for one tap but not others, the problem isn’t the heater itself—it’s usually something downstream.
Think of your hot water system like a network of pipes. The water heater sends hot water through a main line, then branches off to different fixtures. If only the kitchen sink gets hot, the issue might be a clogged aerator, a faulty mixing valve, or a broken shutoff valve under the sink that’s restricting flow elsewhere. It could also be a broken tempering valve—a safety device that mixes hot and cold water to prevent scalding. If it’s stuck, it might let hot water through the sink but block it from reaching the rest of the house.
Don’t assume it’s a plumbing problem. Sometimes the water heater is fine, but the pipes leading to your shower or tub are corroded or collapsed, especially in older homes. If you hear gurgling or notice low pressure in the bathroom but not the kitchen, that’s a red flag. You might also have a faulty recirculation pump if your home has one—it’s supposed to keep hot water moving through the pipes, and if it fails, only the closest fixture (often the sink) gets hot water quickly.
Check the simplest things first: turn off the water, unscrew the sink’s aerator, and clean out any debris. If that doesn’t help, test the hot water at another fixture—like the bathtub or laundry room. If none of them work, the problem is likely the water heater’s dip tube, thermostat, or heating element. If only the sink works, it’s probably a valve or pipe issue. Either way, you need to know which one before calling someone.
People often rush to replace the water heater when they don’t have hot water—but if the heater’s still heating water and only one tap gets it, you’re wasting money. Fixing a valve or clearing a pipe is cheaper than replacing a $1,000 tank. And if you’ve got an 8-year-old or 10-year-old system, you’re right on the edge of when repairs start to make less sense. That’s why knowing the difference between a plumbing blockage and a failing heater matters.
In the posts below, you’ll find real fixes people have used to get hot water back—whether it’s resetting a water heater, cleaning a valve, or diagnosing a broken pipe. No fluff. No guesswork. Just what actually works when your hot water disappears everywhere but the sink.
If your shower has no hot water but the sink does, your water heater is fine-something’s blocking the hot water just to the shower. Common fixes include cleaning the showerhead, replacing the mixing valve, or flushing the pipe.
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