As the weather is becoming cooler in Hong Kong, there's nothing more comforting than indulging in a hot shower to unwind and beat the chill. However, imagine your steamy shower turns ice cold or gets boiling hot all of a sudden — it can not only ruin your shower experience, but the abrupt change in temperature can also make you sick.
No matter what type of water heater you are using, whether it’s instantaneous water heaters or electric storage water heaters, they are all prone to having this “Cold Water Sandwich” problem. In this blog, we’ll go over 4 common causes for water heaters running hot and cold, as well as 2 quick fixes you can do at home to help restore your water heater to prime condition.
4 common causes for heaters to run hot and cold
Generally speaking, there are 4 common reasons why your water heater temperature is switching hot and cold:
Reason #1: Insufficient water pressure
Hot water supply is directly related to water pressure. In other words, having a low boiler pressure can affect the heating system's efficiency, which undermines the ability of the tempering valve to control the water temperature steadily. Some gas storage hot water heaters use gas burners to ignite the pilot light, and insufficient water pressure can prevent the burner from functioning properly, causing the water to run hot and cold.
Reason #2: Adjusting the water temperature incorrectly
It's possible that your shower runs hot and cold intermittently simply because you are not adjusting the water temperature in the right way. Most people will turn hot water all the way up to get warm and then slowly turn it down to find the right temperature. In fact, it is not a proper way to use a water heater. When you turn hot water into cold water, the heater will then reduce its water pressure accordingly to adjust the temperature. Some water heaters will even turn off the burners to stop the gas flow, which explains why the heater is running hot and cold back and forth.
Another reason that can cause hot water to turn cold so quickly is the overuse of the heating system. If too many people are using hot water at the same time, chances are, the usage of hot water in the household will outpace the water heater's capacity. It will in turn, cause the pressure to drop in other piping and dilute the hot water supply, causing the shower room to run out of hot water.
Reason #3: Improperly lengthened piping system
Another reason why your water heater is running hot and cold is the improperly lengthened venting pipes. Some Hong Kong households may not be able to install water heaters close to their bathrooms due to the limited space. As a result, these buildings tend to install longer pipes to carry hot water to the shower room. However, since water heaters require direct connection with the supply and return lines, long pipelines can often cause a faulty piping system that interferes with the flow of hot water, reducing the efficiency of providing hot water in time.
Reason #4: Accumulation of minerals that clogs the tank and pipe
The tank is the most important part of a water heater. Hard water carries minerals such as calcium, iron, and magnesium, which can build up on the inside of the tank, causing the tank to lose the capacity to hold a sufficient amount of hot water. The accumulations of minerals can also cause the inlet pipe to get clogged over time, which will interfere with the heater’s ability to effectively control the temperature.
If none of the above reasons are responsible for your heater to run hot and cold, you should seek professional help and have your water heater checked.
2 ways to fix your heater from running hot and cold water
Apart from changing the installation and correcting the way you use your water heater, there are 2 simple ways that can help you fix the water heater from running hot and cold:
Method #1: Check the voltage on the water heater
One reason why your water heater is running hot and cold is because of the lack of sufficient voltage since a power surge can affect the tank's ability to produce hot water. You can therefore check the heating elements on your heater next time you experience hot and cold water when showering and replace the battery if necessary.
Method #2: Unclog the shower spout
Spouts can get clogged over time because of the buildup of mineral deposits, which affects the water pressure and causes the water heater to run hot and cold. When you notice a sudden change of temperature next time when you are taking a shower, simply check your shower spout to see if it’s clogged, and replace the shower spout if necessary.
Leave a Comment