Thermostatic Shower Valve Problems

Thermostatic shower valves are beneficial to use in bathrooms because you can set the temperature of the water at the desirable range. You do not have to adjust them manually repeatedly for hot and cold water.

Thermostatic shower valve problems include debris and scale build-up, corrosion, sudden fluctuations in water temperature, faulty seals, insufficient water flow, worn-out valves, non-calibrated temperature sensors, and blocked inlet filters.

These valves are connected with hot and cold water supplies to mix the water at a specific temperature. You can see fluctuations in water temperature during bathing because of faulty and broken fixtures.

Problems Solutions
Debris and scale build-up Dip the cartridge in a vinegar solution
Corrosion Replace old valves with new ones
Sudden fluctuations in water temperature Call plumber
Faulty seals and leakage Replace valve seal
Insufficient water flow Unclog the shower head or inlet filters
Wear and tear of valves Replace the thermostatic shower valve
Non-calibrated temperature sensors Hire a mechanic to calibrate the sensor
Blocked inlet filters Add new inlet filters or clean previous ones

Debris and scale build-up

The debris build-up on their parts is common and leads to the malfunction of thermostatic valves. In addition, the tank water contains several impurities and dust particles because of their poor cleaning and maintenance.

The dirty water can also clog or jam up these fixtures. In addition, tap water is rich in minerals that can cause the limescale to build on its internal parts.

These start to function abruptly when their internal parts are accumulated with dust and lime scale layers. Clean the cartridge and remove the dirt residues from its surface.

Remove the cartridge and dip it in the vinegar solution for a few minutes. The vinegar can dissociate the mineral builds up and break dirt particles.


These valves have their specific life span, and their working abilities start to decrease after that period. On average, the thermostatic shower valves can last about 9 to 12 years.

Moreover, longevity depends on the proper maintenance and type of water. The functional performance and efficiency decrease when they become old.

In addition, old ones are also more vulnerable to corrosion. You can identify the corrosion on its internal parts from the dark brownish color of the water.

You can see the dark brown water first when you open the faucets of warm side showers. Replace them with new ones which are less susceptible to corrosion-related damage because of their new parts.

Sudden fluctuations in water temperature

Many people complain that water from shower heads does not run at the right temperature when you set them at a specific range.

It fluctuates between hot and cold conditions and causes a problem. The issue comes due to the incorrect alignment and installation of thermostatic valves.

The temperature fluctuations come due to damaged O-rings. The issue comes from broken thermostatic elements that cannot maintain the temperature or smooth flow.

You cannot identify the O-ring or damaged thermostatic elements at home. Therefore, it is necessary to call an expert plumber to resolve the problem without causing more damage.

Faulty seals and leakage

Many people complain about the dripping of water on the floor. The issue comes when showers are not working and when you turn off the water supply.

The constant dripping can damage the tiles and make them loose. In addition, it increases mold growth, and you can feel a musty smell from the bathrooms.

The constant standing water on the floor makes the soft spots on their surface and decreases their durability. In addition, the constant dripping of droplets occurs due to damaged or poor seals.

The loose seals cannot control the water flow, and you can see dripping from the shower heads. Replace the seals with a new one and select according to the valve’s model, brand, and size.

Insufficient water flow

Many people face the problem of insufficient water flow from the shower heads after setting the temperature at the desirable ranges.

The pressure decreases when they become old and have less working efficiency. In addition, the issue comes due to their broken parts and their malfunctioning.

You can face the problem of decreased pressure due to blocked shower heads. Furthermore, the clogging of inlet filters and damaged shower hoses also reduce the flow.

Unclog the shower head and dip it in vinegar. Replacing the kinked or stretched shower heads is necessary for a smooth water flow.

Wear and tear of valves

The thermostatic valve’s accuracy can last for less than 12 years, and you can see malfunctioning in their system after this specific span.

These valves can break over time, and their working accuracy also reduces. You can see changes in the temperature of the water and its insufficient flow.

Moreover, the frequent changes in water temperature increase the risk of wear and tear in their internal parts. in addition, sudden changes in pressure also stress their components, and they can wear out.

Replace the valve with a new one when you have insufficient pressure and temperature fluctuations.

Non-calibrated temperature sensors

The temperature sensor is the small equipment inside the shower’s mixing chamber. The integral function of the sensor is to maintain the water temperature according to the pre-set range.

It allows the mixing hot and cold water when you turn on the shower and ensures frequent flow. The sensors become faulty and do not regulate the temperature, disturbing the water flow.

After detecting the temperature, it adjusts the flow on the warm and cold sides. You can see fluctuations in temperature due to poorly calibrated sensors.

It is better to hire a mechanic to calibrate thermostatic shower valves. It is a difficult and tricky procedure, and you cannot adjust the temperature-controlling valve at home.

Blocked inlet filters

It contains the inlet filters on their inner side to remove the small particles and impurities from the water before it reaches the shower heads.

The inlet filters get clogged with impurities and dust particles. The clogged inlet filter disturbs the temperature of the water, and you can see fluctuations in it.

Most of the time, this hot water cannot come outside because of blocked inlet filters. This is because the high amount of minerals in water builds up on these filters and clogs them.

It is problematic for people to shower in cold water in freezing winters. Moreover, it is also annoying for them when cold water starts to come from the shower heads suddenly.

The fungus particles in water can also clog these inlet filters and restrict the movement of warm water. As a result, the blocked filters cause constant running of either cold or hot water.

It is necessary to clean them by removing them from the fixtures. Sometimes cleaning does not help or resolve your issues, and you have to replace them.

These are less costly, and you can replace them quickly with a new one.

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