Did you open your shower faucet this morning to enjoy a relaxing hot water shower but be greeted with a blast of icy cold water? I know how frustrating it was! More often than not, this unsettling experience of yours can be attributed to your hot water mixing valve problems.
However, the underlying reasons for the shower mixing valve no hot water include:
- The shower valve is not adjusted correctly
- Blockages in the valve
- Water leaking from the valve
- Air lock in the hot water line
- Or only due to a bad shower valve itself?
Before considering anything else, make sure you have adjusted the valve to your desired temperature setting. Inspect the valve for any signs of blocks or leaks and fix those!
Don’t hassle you if you are dealing with a completely defective valve as we are here for you bringing the easiest replacement procedures in our guide!
So without getting late, let’s dive right in!
What Is A Shower Mixing Valve & What Does It Do?
A shower mixing valve is a specially designed plumbing valve to control the hot water outlet temperatures to safe levels by mixing hot water and cold water.
In general, the valve is used in households, schools, and health and social care environments in order to protect the individual by reducing the risk of scalding from very hot water from showers, baths, and wash-hand basins.
Typically a shower mixing valve functions through an internal thermal element that is used to blend hot and cold water. The valve has separate inlets for hot and cold water. When the hot and cold water enters the mixing valve through these inlets, it carefully starts blending the streams using that thermal element to output a mixed water stream at a safe level.
Anyway, there are two primary types of shower mixing valves.
Pressure-Balancing Mixing Valve: These types of valves automatically adjust the hot and cold water to maintain a consistent water temperature. For instance, it maintains a balanced flow of water between the hot and cold sides.
Thermostatic Mixing Valve (TMV): These valves use a temperature-sending mechanism to sense the water temperature and mix the hot and cold water accordingly.
Possible Reasons & Solutions For Shower Mixing Valve No Hot Water [Quick Overview]
Before heading over to the details, take a short glimpse at the quick table below, highlighting all the probable reasons and solutions for why there is no hot water in your shower:
| Probable Reasons | Possible Solutions |
| Incorrect adjustment of the valve | > Adjust the valve to your desired temperature setting |
| Blocked mixing valve | > Inspect the shower valve for any clogs and clean it thoroughly. |
| Shower mixing valve is leaking | > Examine the valve for any signs of wear and tear. > Tighten the loose connection or replace the worn-out parts |
| Air lock in the hot water supply line | > Bleed the trapped air from the water line. |
| Bad shower mixing valve | > Replace the bad valve with a new one. |
How To Fix Shower Mixing Valve No Hot Water [Easy Solutions]
Join us till the end of our comprehensive guide to get to know all the potential reasons for no hot water in your shower mixing valve with easy DIY solutions:
1. Wrong Adjustment Of The Valve
If there is no hot water coming from your shower mixing valve, the best possibility is the valve is not adjusted as it should. It is crucial to adjust the shower mixing valve as per the manufacturer’s instructions to ensure its accurate functionality.
As mentioned above, the valve equips to more fluid streams at different temperatures which it combines to produce a mixed stream at a desired temperature.
To get these streams, it uses separate inputs for hot and cold water along with a control mechanism to adjust the temperature of the mixed water output.
But in case the water inputs are not adjusted correctly, it is obvious you are getting output water at your desired temperature.
So as for the first step, when you are confused about how to fix the shower valve with no hot water, let’s start by adjusting the shower mixing valve as recommended.
How To Adjust A Shower Mixing Valve?
It is easier to adjust a shower mixing valve. However, the process may differ depending on the specific model and manufacturer. Here are the general steps to follow:
Step #1: Start by identifying the location of your shower mixing valve, it would be installed near the shower or bath, on the side of the wall, or behind an access panel.
Step #2: Before heading to the adjustment procedures, turn off the water supply from the main supply line to prevent accidental scalding or damage to the valve.
Step #3: Depending on the model, you will find a handle or cover over the valve assembly. Gently unscrew the handle or remove the cover using a screwdriver to access the temperature adjustment knob like in the picture below:
Step #4: Once you have got access to the adjustment knob, take a socket wrench and adjust the knob to your desired temperature setting. Here you will see H & C, highlighting Hot and Cold on the valve body.
Some of the mixing valves have a digital display that allows users to adjust the temperature using buttons.
Step #5: After making any adjustments, turn the water supply back on and test the water temperature. For instance, use a thermometer to measure the temperature of the water leaving the tap.
If everything is okay, reassemble the handle over it back in place, and enjoy your shower!
What Temperature Should Thermostatic Mixing Valves Be Set At?
The Thermostatic mixing valve is designed to blend hot water and cold water using an internal thermal element to produce a mixed water stream at your pre-set temperature. Thus it is essential to adjust the valve temperature accurately.
According to the manufacturer’s instructions, these types of valves should be set to exceed a maximum temperature of 49C or 120F. It’d be best if you set the temperature between 39°C and 43°C to ensure a safe shower experience.
If you set your shower mixing valve temperature too low or too high, it has several consequences. Like if you are setting the temperature too low, you may not have a sufficient supply of hot water for your needs as well as encourages the growth of harmful bacteria, such as Legionella.
Conversely, if you are setting the temperature too high, it poses a risk of scalding and burns in a matter of seconds, especially to vulnerable individuals like children and the elderly. Thus the temperature setting for a thermostatic mixing valve should be set to a safe and comfortable level.
2. Blocked Shower Mixing Valve
Recently I installed a new shower mixing valve and it doesn’t seem to work properly. When I inspected the shower mixing valve, I found only a little water dribbled out. Following the instructions, I delved deeper and found stuck debris and sediment in the valve.
Blockage in the valve is another major reason why you are not getting hot water from the valve. Over time, it is common that the passageways of the mixing valve can clog up due to minerals, debris, or foreign objects present in the water supply.
If you have hard water in your area, containing high mineral contents like calcium and magnesium, it is obvious the hard mineral accumulates within the mixing valve over time and creates blockages, leading to reduced flow rates.
Sediments can also partially block the water flow through the valve as well as affect the ability to achieve the desired water temperature.
How To Fix:
If you suspect sediment and lime-scale deposits clog the shower valve water passages, it is easier to deal with the issue. You just need to thoroughly clean the valve assembly. Wondering how to do so? Here are the simple instructions to follow:
Step #1: First off, make sure you have turned off the water supply to your shower. Using a screwdriver or Allen wrench, remove the screws and fasteners holding the handle in place and get access to your shower mixing valve.
Step #2: Now if there are minor deposits in the valve you can easily clean it by flushing out the valve. For instance, use pliers or an adjustable wrench to remove the retaining clip or nut, holding the shower cartridge in place.
When done, pull out the cartridge from the valve body. If needed, use a cartridge puller.
Step #3: Anyway in this step, turn the water supply back on at full speed and let it run for 60-90 seconds. It should flush out stick debris from the water supply lines of the valve.
Step #4: In case you suspect severe clogs in the valve inside, you will need to disassemble it from the connection. Remove the shower mixing valve without difficulty.
Step #5: Now clean the valve with warm, soapy water and a brush. It’d be better if you soak the valve in a vinegar and water solution to loosen the grime and mineral buildup easily.
Step #6: When done, rinse the valve with clean water thoroughly. After cleaning, put everything back in place and turn on the water supply. Hope you will get hot water now.
3. Shower Mixing Valve Is Leaking
If you are not getting hot water from your shower mixing valve, another best possibility of damage is in the valve assembly. If there is any minor leakage in the valve due to damage, water starts dripping out from the water supply lines, reducing the functionality of the valve.
Over time, seals and O-rings inside the valve degrade, leading to leaks. A damaged or incorrectly seated O-ring or seal allows water to seep through gaps and for that reason, the valve fails to mix the cold water and hot water at a perfect ratio.
Also, loose connections at various connection points in the shower valve can cause leaks.
How To Fix:
Whatever the fact is, you will need to inspect the valve entirely for any signs of damage. Look for loose connections at the pipe joints, seal, or O-ring of the valve and tighten it using a wrench.
[Before reinstalling the seals and O-rings, make sure you are applying a thin layer of silicone-based plumber’s grease to facilitate smoother operation]
Sometimes simply tightening the connections like loose nuts or fittings can often stop the leaks.
In most cases, a damaged cartridge inside the mixing valve is the culprit that is causing water leaks from the valve assembly or out of the wall. For instance, you will need to inspect the cartridge and pull it out from the wall. Replace if required.
Adjust the valve and test the temperature and water flow rate to ensure it functions correctly.
4. Air Lock In The Hot Water Supply Line
While struggling with no hot water issue from your shower after long trying, another best possibility is you are dealing with an airlock in the water supply lines. Airlock in the water supply line is a situation in which air is trapped, preventing the flow of water through the pipe.
In most cases, airlocks in the hot water supply line of the shower mixing valve completely block the hot water flow.
Don’t worry! It is easier to bleed air from the water supply line.
How To Fix:
If a significant amount of air is trapped in the mixing valve, follow the steps below to deal with the issue:
Start by turning off the water supply to your shower. You can do it from the main water shutoff valve of your house that supplies water throughout your household fixtures. When done, open the affected shower faucet or fixtures to its fully open position. This will allow air to escape when you turn the water supply back on.
If there’s an airlock in the valve inside, carefully remove the handle and get access to the valve stem. Turn on the water supply and let the water run at a slow, steady flow. Allow the water to run for a minute to ensure that the airlock is completely cleared from the faucet.
When done, hope you will get hot water as before.
5. Bad Shower Mixing Valve
After resolving all the above factors if still there is no hot water from your shower, be sure you have a bad shower mixing valve. Over time, the internal components of a mixing valve degrade due to regular use and exposure to water. This damage leads to a decrease in the valve’s performance, resulting in a lack of hot water flow.
In some cases, lack of regular maintenance, including cleaning and proper lubrication of the valve leads to several problems and eventually failure. All that signifies that you need a replacement shower mixing valve.
Other Major Symptoms Of A Bad Shower Mixing Valve
Before heading over to the replacement procedures, let’s have a short glimpse of other major symptoms of a bad shower mixing valve.
Insufficient Water Pressure
When you have a bad shower valve it is obvious you will deal with an inadequate water flow rate from your shower fixtures. It mainly happens due to the rust and slime scale build-up in the shower valve that restricts the water from passing through normally.
This reduction of water pressure will highly affect your shower experience. This reduction of water pressure will highly affect your shower experience.
Difficulties In Using The Controls
A bad shower mixing valve fails to mix the hot and cold water correctly, making it difficult for the users to use the controls. In most cases, it occurs when the valve is not greased enough. Besides a faulty cartridge is another major factor that causes troubles in using the hot and cold water controls.
Water Is Leaking
A faulty shower mixing valve is the main factor that leads to water dripping out in the shower area or surrounding walls, even when the water is turned off. For instance, physical damage or wear and tear causes cracks or holes in the valve, causing water to leak out. In most cases, it is an obvious sign of a broken cartridge inside the valve. For instance,
Strange Noises
A faulty shower mixing valve produces unusual noises like rattling, clunking, or gurgling sounds during operation. At times a loose or improperly installed shower valve causes vibrations in the plumbing system as water flows through it, it leads to humming or rattling noises.
Temperature Fluctuations
A malfunctioning mixing valve causes inconsistent water temperature. You will experience a sudden fluctuation of the hot to cold water, either too hot or too cold while showering.
How To Replace A Bad Shower Mixing Valve?
Well, when you are certain about your bad shower mixing valve, nothing but you will need to replace the mixing valve. For instance, you can call in a pro if you aren’t skilled enough in plumbing works or follow our assigned guidelines below to complete the task by yourself:
Step #1: Start by closing all the faucets and turning off all the water supply lines so the remaining water can drain.
Step #2: Locate your old shower valve location where it is installed. You can reach it from inside the shower stall or from the wall outside the bathroom. If you want to get access to the wall outside the shower, you will have to cut through the drywall to get to the valve.
Step #3: Remove the knobs and pry off the cover plates in your shower. Now wrap the tab spout with a thick cloth and then unscrew it using a pliers.
Step #4: Now take a tubing cutter and carefully cut out the hot and cold water supply lines to the spout and shower head.
Step #5: When done, you can easily remove the old valve now. Before attaching the new valve, apply the plumber’s grease to lubricate the O-ring on the new shower valve.
When done, Insert the new valve into the wall
Step #6: Connect the water pipes to the existing plumbing system. Before doing any soldering, dry-fit all connections together.
Step #7: Use a wrench to secure the connections to the valve. Adjust the valves and then use a thermometer to measure the temperature of the water coming from the shower.
Step #8: If everything is okay, install a large chrome cover plate with the chrome sleeve and slide it over the valve.
Step #9: Fasten the handle base to the valve and tighten it with a hex-key wrench. Finally, press the handle onto the stem, making sure to align it to the “off” position.
Step #10: Secure the handle and lastly snap the small index cover over the handle screw. Congratulations, you are done!
How Much Does It Cost To Replace A Shower Mixing Valve?
The average cost to replace a shower mixing valve would be between $110 and $750, including the material, the cost of labor, and other replacement costs. Typically, a shower mixing valve costs between $40 and $350.
The cost to replace a shower mixing valve will depend on the types of valve you are installing and the ongoing rates for plumbers in your area. Here is a short breakdown of the estimated cost to replace and install a new shower mixing valve:
Labor Cost
As mentioned above, it would depend on the hourly rate in your area. In general, it would be between $45 to $200 per hour. Plus, it would take two to four hours on average to complete the replacement task. That means you will expect to pay around $90 to $400 for your plumber excluding the material cost.
Material
There are different types of shower mixing controls available in the market such as manual mixers, thermostatic shower mixers, digital shower mixers, or smart shower mixers. Have a glimpse at the average cost of these valves:
| Shower Mixing Valve | Price |
| Manual Shower Mixer | $182 |
| Thermostatic Shower Mixer | $60- $240 |
| Digital Shower Mixer | Up to $600 |
| Smart Shower Mixer | $170 – $200 |
Additional Costs
Generally, a shower mixing valve kit contains all the parts to replace your existing valve, in most cases, you will get a new shower head included with it.
But in case you are considering buying individual parts, be sure you will have to buy other needed parts along with the replacement shower valve parts that cost more.
But for instance, you will need to ensure the individual parts match the valve. In case you don’t want to get this hassle, it’s worth investing in the kit.
How Long Do Shower Mixing Valves Last?
A properly installed shower mixing valve should last for about four or five years. But typically it would depend on the type of shower you are using and the mineral contents in the water in your area. With proper cleaning and maintenance, you can easily increase the longevity of the shower valve.
It’s essential to follow the manufacturer’s guidelines for maintenance and servicing. To ensure the proper functionality of the shower mixing valve, regular testing is a must.
It would be best if you can inspect your shower mixing valve once or twice a year by a professional plumber. He will help identify any potential issues or wear and tear that require attention.
Thermostatic Mixing Valve Maintenance Tips
Maintaining a shower valve is essential to ensure consistent and comfortable water temperatures while showering as well as to prevent costly repairs due to malfunctioning.
Here are some pro tips to follow to maintain and extend the lifespan of your shower mixing valve:
- First off, periodically inspect your shower mixing valve for any blockages and clean it properly. Even it is crucial if you are living in a hard water area, containing high mineral content. For instance, consider flushing the valve once every six months to remove sediment and debris that may accumulate over time.
- Also, check the valve entirely for visible signs of wear, corrosion, or leaks. Tighten the loose connection or replace the worn-out parts like old seals, O-rings, gaskets, or other parts that may be deteriorating.
- As with other steps, regularly the temperature settings on the valve. If required, adjust it according to the manufacturer’s instructions. It is essential to prevent sudden and extreme temperature fluctuations, reducing the risk of scalding for your family members.
- In addition, you should keep a record of your valve’s maintenance history. It will help you to track down when you last serviced the valve and what actions were taken.
- Most importantly, take necessary safety precautions whenever you are working with your plumbing components. Turn off the water supply first and it’d be best if you wear appropriate safety gear when working on the valve.
FAQs:
Can I Replace A Shower Valve Myself?
Yes, definitely you can replace your shower mixing valve for yourself if you have good knowledge of the plumbing system and the right replacement part for your bathroom fixture. In case you are at a beginner level in plumbing projects, we recommend consulting with a professional for this task.
What is the difference between a Thermostatic Mixing Valve and a Tempering Valve?
Thermostatic Mixing valves or TMVs and tempering valves both are designed to regulate the temperature of water in plumbing systems. But TMVs water is used for ablutionary purposes like washing, showering, and bathing. on the other hand, the tempering valve is used in a situation where the water in the storage cylinder can exceed 60°C
Where TMVs should be installed?
A thermostatic mixing valve should be installed in areas where there is the highest risk of scalding. Frequently they are used in showers to regulate the water temperature. Plus you can install it in bathtubs, sinks, and other faucets. Also, it is crucial in healthcare settings like patient rooms, surgical areas, and other critical locations to prevent serious consequences due to exposure to temperature extremes.
How to Save on Shower Valve Replacement Costs?
Though a shower mixing valve is pricy enough, you can easily save money by sticking with a basic model that fits your cartridge. Also before hiring a professional, you can compare the hourly rates of various plumbers in your area.
Are shower mixing valves universal?
No, shower mixing valves are not universal, meaning you can’t pick any shower valve and expect it to fit in your existing plumbing fixtures. You will have to use the same manufacturer unless you can’t ensure the proper function of the valve.
In Closing!
Beyond any doubt, a shower mixing valve is an essential plumbing device that helps to keep your hot water shower safe and functional. As with this, it is also not uncommon that users deal with shower mixing valve no hot water issues frequently.
This mostly happens due to wrong adjustment of the valve or due to any blockage in the plumbing system. In most cases, a bad shower valve is the culprit itself that needs replacement.
Follow the instructions mentioned above to deal with the malfunctioning mixing device of your shower system and ensure a hot, safe, and comfortable shower experience.
Note: You can also read our guide on why no cold water in the shower after replacing the cartridge and how to fix it.
About Atikul
Atikul Islam shares his expertise with various tips & tricks to fix the problems with home appliances related to toilet, kitchen, bathroom, heating, & cooling systems. Read to know more about Atikul Islam.