Why is My Shower So Cold? l Watermark Plumbing
top of page

Why is My Shower So Cold?



This week, we’re going to talk about your shower controls, and why you’ve had to call in the plumber to fix your very hot or very cold shower. Read through this and next time you may be able to take care of it yourself!


All single handle shower faucets use what a combination of what is called a “Pressure Balancing Valve” and a “Cartridge” to regulate the temperature and pressure of the water in your shower. Depending on the brand, they can come as two separate pieces, or all in one. As you turn the handle in your shower from cold to hot, the cartridge allows more hot water and less cold water into the faucet. These cartridge and pressure balancing valves can be quite finicky – they are made up of many very small components that need to be working properly in order for everything to function as it is supposed to. Unfortunately, over time, mineral deposits and small debris particles can cause these parts to malfunction. This is when you start to run into issues and call the plumber to figure out what’s wrong.


Today, let’s take a minute and go through the steps to do this yourself if you wanted to give it a try! I want to give you fair warning before you were to try this on your own; replacing a cartridge is usually quite simple, but things can go wrong quickly. When things go wrong, you are often left without water in the house until everything is resolved – so be aware of the risks before you start taking everything apart!


The first thing you are going to do when replacing a cartridge is to figure out which one you need. Unfortunately, cartridges are all brand specific (and there are different models within each brand), so this can sometimes be difficult! I have found the easiest way is to often go directly to the manufacturer’s customer service and have them tell you the model you need. You don’t want to go through all of the steps to pull out a cartridge and have your replacement be the wrong one!


Next, you are going to shut the water to the house and make sure to drain it as best as possible – open faucets and allow the water to stop. Also, open the shower valve and make sure no water comes out.


Third, you are going to take the shower control apart and pull out the old cartridge. Remove all handles, cover plates, escutcheons, etc. This can sometimes be a bit complicated, so make sure you note what pieces go where. You don’t want to have replaced the cartridge successfully and then not be able to put everything back together!


After you’ve replaced the cartridge, put the shower controls back together again, and turn on the water to the house. If done properly, everything should be back to normal. There is always the off chance that there is a secondary issue, but most of the time, replacing the cartridge and pressure balancing valve is the first step in fixing temperature/pressure issues.


I want to give you all one more warning – before running out to take this on yourself, know that it is an “all or nothing” situation. For example, if you mistakenly bought the wrong cartridge, then somehow broke the faulty one trying to get it out, you won’t have water in the house until you have the right parts! Alternatively, if you have something happen that didn't fall into line with what we spoke about today, there is the very real chance you could cause some damage. Please do not try this yourself if you are at all uncomfortable! Be sure to read manufacturer guidelines before taking something like this on.



15 views
bottom of page