Nothing compares to spritzing cool water on your face after a strenuous day in the scorching summer sun. Sadly, many individuals deal with the common problem of warm water coming from a cold water faucet. This irritating problem may have several causes. 

A qualified plumber should investigate if your cold tap consistently produces hot water. But first, you need to figure out what is warming the cold water side of the faucet

This post will investigate “warm water from cold tap in summer” and the causes and possible solutions. 

What Causes Warm Water From Cold Tap In Summer

1. Close Proximity of The Pipes

Typically, bathroom taps have a pair of knobs: one controls cold water and the other warm to hot. Due to the two distinct knobs, cold and hot water are supplied by two separate pipelines that are parallel to one another. The plumber may occasionally place the hot water line near the cold water pipe. 

As a result, the warm water line’s heat wave will cause the cold water pipe’s water to warm up. And you are aware of the impact of this issue. You can speak with the plumber you hired to handle this problem and tell them to keep a small space between the two pipes to solve it.  

It may take a while for the water to begin to cool down after using hot water because the faucet also starts cooling off. The water ought to begin to get colder after five to ten seconds.

2. Heats Ventilation Duct

As space heaters and furnaces are used constantly throughout the winter, the ventilation duct must be conducted frequently. Due to the heated air continually flowing through these lines, it became pretty hot to the touch. 

If the cold water pipe in your home is very close to or contacts the vent duct, the fluid inside the line may warm up. Always keep enough space between your water and duct pipes to prevent this issue.

Some professionals also suggest using an air conditioning system to manage the temperature in the duct. 

Warm Water From Cold Tap In Summer

3. Faulty Thermostat

When troubleshooting this issue, you may occasionally discover that the issue above may arise if the thermostat is malfunctioning or broken. 

The malfunctioning water heater will ultimately trigger a heatwave that will heat the water from the cold tap by overheating the hot water. As the temperatures mix, the water that holds cold water will gradually warm up.

Replace your broken thermostat or install a more recent water heater to avoid this issue.

4. Poor Plumbing 

Households and to save money, so they often call the least expensive plumber. You get what you pay for home repairs. The least costly plumber in town is also the least skilled. Sometimes unskilled plumbers connect the hot water pipe to the cold water pipe.

5. Wrong Temperature Settings of the Faucet

There might be a problem with your water tap if you discover that you get warm or hot water. To be sure nothing is broken, inspect the links under the sink and the faucet.

To check if there is a problem, you may employ the valve to turn off the source of hot water below the sink. Warm and cold water must be blended at the faucets. If there is a malfunction, it can cause the hot water line to open as opposed to the icy water line. If the faucet is damaged, replacing it is the most straightforward fix.

6. Problems With Your Water Heater

Your water heater might malfunction if warm water splashes from the cold faucet. Since the water is heating up slower than it typically does, the water heater might be past its prime. Rather than keeping the cold and hot water separate, it can mix the two.

The bottom of your tank should typically have cold water, but as the expansion tank ages, it may be unable to keep the water there. See if the water heater’s panel has any messages. To prevent problems, it should be maintained frequently. Your heater may need to be replaced or repaired by your plumber.

The water heater’s settings could also be wrong, causing it to overheat its water. It may produce a hotter result than anticipated if combined with cold water. Examine the temperature controls to ensure your heater is moderately hot. 

7. Something Is Wrong With the Temperature Setting of Your Faucet

The water tap might be problematic if you receive warm hot water from the cold faucet. To be sure nothing is broken, inspect the links beneath the sinks.

You can use the valve to turn off the heat source beneath the sink to check for a problem. Cold and hot water must be blended at the faucets. If there is a malfunction, it can cause the hot water line to open as opposed to the cold water pipe. If the faucet is damaged, replacing it is the most straightforward fix.

Related Post: No Hot Water After Freezing Weather

How to Make Your Tap Water Colder During Summer 

Many homeowners are increasingly switching from metallic lines to plastic ones. While plastic lines are less expensive than metal pipes, they are also less well-made and boast a different level of insulation. Additionally, most plastic pipes will pass through the attic of a house, which significantly raises their temperature and results in cold taps flowing warm during the sweltering summer.

Intermingling lines, the problem where hot water lines inevitably cross over cold water pipes, is one of the other often occurring sources of warm water from cold faucets. Intermingling pipes can cause various plumbing problems, such as heat trap problems, cartridge damage, and loose valves.

Tips To Help Cool Down Your Home’s Tap Water

The first thing you must understand about this typical summertime piping problem is that you will need more than just running the faucet longer. 

This will not only be environmentally unfriendly but also waste water and increase your utility costs. You’ll be safer finding a solution that will last when your cold tap water gets warm.

The following advice will assist you in finding the best long-term solutions to address your lack of cold water adequately:

  • Try touching the pipes in your sink and pay close attention to their temperature. You should start following the lines back to the source of the problem if they feel warm. Most of the time, these problems will begin close to a sink, but if not, you’ll require plumbing experts to check everything out.
  • Next, you should inspect the cartridge in your faucet. Every contemporary sink faucet has a cartridge to help direct the water flow; if the cartridge is broken, this may be the cause of your hot water coming out of your cold tap. 

To at least check the functioning of your cartridge, all you have to do is use a screw to unhook the faucet and look to see if it’s broken or not. You should have one of our sink plumbing repair experts change the cartridge if it is broken.

  • You can also tighten the valve with a pipe wrench if your sink’s cartridge operates flawlessly. Tightening valves is one form of preventive care that needs to be done regularly. After reviewing the three suggestions above, try turning on your water to see if it functions as it should. You’ll need the assistance of plumbing professionals to investigate the plumbing network further if it still needs to be fixed.

You can also install a radiant barrier in the attic. This will reduce the amount of heat directed to the pipes by the attic. 

Adjust recirculating timer on the water heater to allow water to flow constantly. Moreover, you can install a check valve in the recirculating plumbing to prevent warm water from getting into the cold faucet.

Warm Water From Cold Tap In Summer

Why Exactly Does Warm Water Sometimes Come Out Of A Cold Tap?

When the immersion heater malfunctions in the “on” position, hot water leaks from cold faucets. This will continually heat water in the hot water cylinder. After traveling up the expansion pipe, boiling water expands and vents back into the cistern used to store cold water.  

Since the cold taps—particularly the bathroom ones—are typically supplied by the storage, you may observe hot water pouring from them in this instance. If the storage is the water source, a bathroom may wash with hot water. 

Your kitchen’s cold tap won’t be impacted since it receives its supply directly from the mains. Nevertheless, even if the mains power your home’s cold taps, you can still have this issue with boiling water from the hot faucets.

Related Post: The Shower Not Getting Hot Water, But Sink Does

Can I Fix It!?

Various fixes for hot water come from a cold tap based on where the issue originated. Here are Four quick fixes to improve the cold water faucet’s flow:

1. Turn Off the Water Supply

Turning off the water flow is crucial before starting any plumbing maintenance. If you don’t want to cause a significant water leak, you must understand what is happening inside the piping. A water valve must be turned off before beginning.

 To be safe, you can frequently cut off the water to the entire side of the house where the water temperature problem occurs. Let the water flow from the faucet to eliminate extra water in the lines.

2. Check Pipe Temperature

You can check the temperature of the pipelines under the sink with your hand when there is no longer any water in them. You check whether the cold water source line is hot, warm, cold, or room temperature; ensure you touch it. 

These are the most straightforward fixes because the source of the issue is frequently found close to the sink. However, you may require professional assistance if the hot water issue’s root cause is far from the sink. 

3. Replace Your Faucet Cartridge

All contemporary faucets include a cartridge inside to redirect water. Your water supply may need to be directed if the tap cartridge needs to be fixed. You can swap out the tap cartridge by unscrewing the faucet, extracting it, and exchanging it for a new one.  

4. Test the Faucet

To test the water supply, swap the faucet and switch the water back on. Check to see if the cold side is chilly or still hot after letting the water run for a few minutes. If the water is still hot even after flowing from the cold tap, you may have a more severe problem on your hands and should seek professional help.


There are many reasons why warm water may come from the cold side of the faucet, especially during summer. And while you can give many DIY approaches in this situation, the best one is to contact a professional plumber. 

This will ensure that you discover all the causes of the issue and set everything right for once. Even so, this post has provided a couple of ways you can try out by yourself if you don’t think the problem needs a pro plumber.