Why Gas Water Heater Is Not Hot Enough?

Even if you’re not a fan of extremely hot showers, having lukewarm water constantly running from your faucets is not a great thing. 

Your gas water heater might not be getting hot enough, in case the thermostat settings are not correct, the dip tube is damaged, or the unit is getting close to the end of its lifespan.  An undersized water heater might also be to blame. 

Why Is My Water Heater Not Getting Hot Enough?

You might have to deal with lukewarm water, if:

  • The thermostat settings are wrong
  • The breaker had tripped
  • The demand for hot water is unmanageable
  • There is sediment build-up in the tank
  • The tank is leaking
  • The dip tube is displaced or damaged
  • The gas valve is broken
  • The water heater is getting close to the end of its lifespan

Why Is My Gas Hot Water Not Very Hot?

When it comes to a gas water heater, all the issues mentioned above might be responsible for the malfunction.

Do bear in mind that if you have an instantaneous hot water heater, then the unit would require moderate to high water flow to light the pilot

Turn the taps on hard and allow the water to run for around 5 minutes. If you start getting hot water, then the problem is the flow rate, not the actual heater.

Read: Why Gas Hot Water Heater Is Not Heating? – Troubleshooting Guide

New Gas Water Heater Not Hot Enough

If you have only recently bought a gas water heater and it’s already failing to provide hot water, then you might have chosen a unit of the wrong size.

You can pick the water heater according to the household size. For example, if there are 1-2 people living in the house, then you’re going to need 23-36 gallons of water, while 2-4 people would require 36-46 gallons.

To correctly choose a tankless gas water heater, you would have to take the temperature rise and the flow rate into consideration. 

Read: Gas Water Heater Thermocouple Possible Issues

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Gas Water Heater Not Hot Enough – What Should I Do?

Adjust the thermostat

Check the thermostat settings of the water heater. Make sure that the water temperature is set to around 120 F.

If you adjust the thermostat and nothing happens, then the device might be faulty and you would have to replace it.

Fix the tripped breaker

Any hot water heater that has an electrical connection also has a breaker. There are gas water heaters that have electric circuits; if that’s your case, then make sure to check the breaker.

At times, simply flipping the breaker back to ‘on’ can help. However, if the appliance continues tripping the switch, it would be better to call a professional.

Get rid of sediment build-up

If your house has hard water, you would have to deal with the mineral build-up in the water heater tank at one point or another. Draining and flushing the tank at least once a year will help prevent this issue.

Find and fix the leak

If you suspect a leak, turn the unit off and try to locate the leaking element. You might want to tighten the connections and, perhaps, replace the valves.

If the actual tank is leaking, you would, unfortunately, have to get a new unit. 

If the dip tube or the gas valve are damaged, then you might want to invite an expert to deal with the problem. 

Read: Why Water Heater Is Leaking?

Gas Water Heater No Hot Water in Shower

If your gas water heater is working correctly, but there is no hot water in the shower, you might want to consider these few things:

  1. The pipes through which the water is flowing are getting too cold (especially, in the winter).
  2. Your shower is too far from the water heater, so the water loses a lot of heat before reaching the actual shower.
  3. The flow rate on your showerhead is too low. The lower the flow rate, the longer it will take the water to heat up.

Should Gas Hot Water Be Instant?

If you have a tankless water heater, then you should be able to receive hot water instantly.

A tank unit, on the other hand, would need around 30-40 minutes to heat up the cold water.

Bear in mind that this time is required only when new water is fed into the unit. Usually, water heaters with a tank store the water and maintain the desired temperature all the time (which is not energy-efficient). 

Read: The Best Temperature For The Water Heater And Why?

What Setting Should Hot Water Heater Be On?

140 degrees Fahrenheit is the most common default setting of water heaters. However, experts recommend lowering the temperature to 120 F to avoid scalding.

You shouldn’t set the temperature below 120 F as this is the minimum setting required to keep a wide range of bacteria from developing in the tank. Such a temperature also slows down corrosion and mineral build-up in the system

Is 50 Degrees Hot Enough for Hot Water?

50 degrees Celsius is too hot. If the water coming out of your faucet is only a few degrees higher than your body temperature (around 37 C), it can give you a first-degree burn.

When it comes to Fahrenheit, the optimal temperature for shower water is no higher than 105 F. However, keeping the temperature between 98 F and 101 F is recommended. 

Why Is My Hot Water Running Out So Fast?

If you have a new water heater, then the chances are high that the unit is undersized.

If you started running out of hot water much faster than before, then a broken dip tube and sediment build-up might be to blame.

A dip tube is a component that pushes the cold water to the bottom of the tank so that it can get heated. If this element gets damaged, then the overall temperature of the water will become lower.

The water that gets delivered in the tank usually contains dissolved minerals that can start forming a layer of sediment over time. The bigger this layer, the less water your unit would be able to heat. 

Read: Does HVAC Include Water Heater?

Why Does My Hot Water Only Last 15 Minutes?

  • Your tank is too small
  • Your unit has a lot of sediment build-up
  • The dip tube is damaged

Does Turning Up Water Heater Make Hot Water Last Longer?

You can make hot water last longer, if you increase your water heater’s temperature, as you will be using less of it to make cold water warm.

However, do bear in mind that by turning up the heater you are also increasing the risk of scalding

How Do I Make My Hot Water Heater Hotter?

The easiest way to make your gas water heater hotter is to adjust the temperature setting.

Bear in mind that older gas units have a temperature knob close to the base (you can turn them to the desired temperature).

Newer gas water heaters have temperature controls hidden behind a panel.  Tankless models usually have an LED panel that you can use to directly adjust the temperature.

How Do I Make My Shower Water Hotter?

Insulate the water pipes

Insulation will help hold the heat in the plumbing lines for longer.

Use a hot water recirculation pump

The farther away the shower from the water heater, the more it is going to benefit from this add-on. 

Such a system can also help you save plenty of gallons of water as you wouldn’t have to waste the cold water while waiting for it to get hot.

Upgrade your showerhead

The flow rate of the showerhead is measured in gallons per minute (GPM). If yours has a GPM under 2.5, then you might want to upgrade.

Why Is My Cold Water Warm?

  1. High water pressure – if the pressure in the system is too high, it might cause your cold water to run hot.
  2. An issue with the water expansion tank valve – such tanks require a pressure-lowering or a one-way valve to stop hot water from flowing into the cold water tap.
  3. Wrong heat trap installation – the contractors have to make sure that the heat trap is placed directly in the water heating inlet; otherwise, the hot water might flow into the cold-water lines.
  4. An issue with recirculating plumbing – if your system has hot water recirculating plumbing, then you might be getting warm water until the heated water gets to the temperature valve.
  5. The vicinity of the plumbing pipes – if your hot-water pipes are too close to the cold-water pipes, the latter can get heated up.