You step into the shower, expecting a wave of warmth to greet you and start your day right. Instead, you’re met with water that’s only lukewarm, leaving you tense and unsatisfied. The chill follows you out of the bathroom and seems to linger as you move through your morning routine. Washing dishes feels less effective, and even laundry doesn’t seem as fresh.
That missing heat becomes a quiet frustration that builds with every task. When your water heater is not getting hot enough, it’s more than a minor annoyance—it’s a daily disruption. You’re left searching for answers, waiting for the comfort you remember, and hoping the fix you find actually lasts longer than a single shower.
What Causes Lukewarm Water and How to Fix It?
Several issues may cause your water heater is not getting hot enough, leaving you with hot water only warm instead of the usual heat. Once you’ve identified the cause, you can take steps to fix the problem.. Below are the most common reasons this happens, followed with solutions—but always prioritize safety and seek professional help if needed.
- Thermostat Issues
When your hot water is luke warm, check the thermostat. It may be set too low. Set it to 120°F for better safety and efficiency. Electric heaters have two thermostats—upper and lower. Adjust both. If one is off, you’ll get uneven heat. A simple reset often helps restore proper temperature without replacing any parts.
Locate the thermostat dial on your unit. It’s on the gas valve for gas heaters. For electric ones, check behind the access panels. Adjust it to 120°F or a bit higher. Don’t go over 140°F to avoid burns. Wait a few hours. Test the water. If the water not as hot as usual feels hotter now, the setting was too low.
- Sediment Buildup
Minerals like calcium and magnesium settle at the bottom of the tank, block heat transfer, and reduce efficiency. This buildup often causes a lukewarm water temperature instead of hot water. If you hear popping or rumbling sounds when using hot water, sediment has likely built up. In that case, your heater needs attention to restore proper temperature and performance quickly.
To fix it, turn off the power (or set the gas valve to ‘pilot’), connect a garden hose to the drain valve, open the valve, and drain the tank until the water runs clear. Close the valve, remove the hose, refill the tank, and restore power or relight the pilot. Flushing once a year prevents sediment problems and extends heater life.
- Heating Element Failure
If you have an electric water heater and the water is warm but not hot, a worn-out or mineral-coated heating element could be the issue. To check, turn off power at the breaker, remove the access panels, and use a multimeter to test both heating elements for continuity before deciding on a replacement.
A faulty element might be the reason your hot water only warm issue keeps coming back. When there’s no continuity, replacement is needed. This process involves draining the tank, removing the access panel, disconnecting wires, and installing a new element. If you’re unsure about handling it safely, hiring a professional plumber is a smart move.
- Gas Supply Problems
For gas water heaters, a steady pilot light is essential to ignite the burner. If it goes out or the gas supply is interrupted, the unit may only produce lukewarm water. A faulty thermocouple can also prevent the burner from working. This issue is a common reason people ask, why is my water not getting hot enough?
Check the pilot light through the sight glass or access panel. If it’s out and water only gets lukewarm, follow the manufacturer’s instructions to relight it. If the flame doesn’t stay lit, the thermocouple may be faulty and require replacement. Since this involves gas components, it’s safer to call a professional plumber for inspection and repair.
- Broken Dip Tube
The dip tube directs cold water to the tank’s bottom to be heated. When broken, cold water mixes with hot at the top, leading to reduced temperatures. If you notice a sudden drop or water is warm but not hot, the dip tube might be damaged and should be inspected as a possible cause.
To replace the dip tube, access it from the top of the tank. Turn off the water supply, disconnect the cold inlet, and remove the old tube. Install a new one securely. This repair needs basic plumbing knowledge but can restore your water heater’s performance and help your system produce consistently hot water again.
- Undersized Water Heater
If your water heater is too small for your household’s needs, you may run out of hot water quickly, especially during busy times. This can make it seem like the water is warm but not hot, but the real issue is the tank emptying too fast. For example, a family of four might need a 50-gallon tank.
If you regularly run out of hot water when multiple taps or appliances are used, your heater may be undersized. In this case, consult a plumber to determine the right size for your household or consider upgrading to a tankless water heater, which heats water on demand and offers better efficiency and a longer lifespan of about 20 years.
- Leaks or Aging Equipment
Leaks around the base or pipe connections can reduce hot water output and may signal a failing tank or valve. This often leads to water not as hot as usual, making daily tasks uncomfortable. Traditional tank water heaters typically last 8 to 12 years, while tankless models may perform well for up to 20 years with proper maintenance.
Inspect the base and fittings carefully for any signs of leakage. If you spot leaks or your unit is between 10 to 15 years old—and the water not as hot as usual continues—it may be time to replace water heater components or the entire unit. Doing so ensures steady performance and helps avoid unexpected hot water loss.
No More Tepid Mornings
When your water heater stops delivering the warmth you rely on, it’s rarely just a fluke—it’s usually a sign of deeper issues like mineral deposits, worn-out parts, or declining efficiency. Ignoring these warning signs can quietly drive up your energy bills, cause leaks, or leave you without hot water when you need it most.
Acting at the first sign of trouble helps you avoid bigger, costlier problems and keeps your home running the way it should. Don’t let lukewarm water become your new normal. Vegas Plumbing Pros is ready to help with expert water heater repair, replacement, maintenance, and upgrades. Contact us today and restore the comfort and reliability your home deserves.
FAQs
Why is my hot water making less hot water
Over time, minerals like calcium and magnesium can build up at the bottom of your water heater, especially if you have hard water. This sediment creates a layer that blocks heat from reaching the water efficiently, making your heater work harder and resulting in hot water only warm instead of hot.
How to tell if your hot water tank is going bad?
If your water heater luke warm, you might notice signs like a lack of hot water, inconsistent temperatures, lower water pressure, unusual noises, a rotten egg smell, visible leaks, rusty or discolored water, or higher energy bills. If your unit is more than 10 years old and showing these symptoms, it may be time to consider replacing it.
Why is my water not getting hot enough?
If you’ve adjusted the thermostat but the water still isn’t getting hotter, the thermostat may be faulty or no longer functioning correctly. Sometimes, related issues like leaky pipes can also affect water temperature. It’s best to contact a licensed plumber or a qualified water heater technician to inspect the system and replace any damaged parts if needed.
How long does it take for water heater to heat up?
A typical storage tank water heater takes 30 to 80 minutes to heat up, depending on the type and size. Gas models generally heat faster, around 30–40 minutes, while electric heaters can take 60–80 minutes. Tankless heaters, however, provide hot water almost instantly since they heat it on demand, which helps avoid problems like water heater lukewarm temperatures.
