If there's an accumulation of sediments in your hot water tank, it can lower your water pressure. The presence of kinks in the flexible water pipes used in water heaters can result in low water pressure. If the shut-off valve isn't fully open, water pressure can drop.
#2 Your Heater DOES Affect Water Pressure
There are two types of water heating systems. The way each system heats water affects your water pressure.
Partially Closed Valve
One of the most common issues that can lead to low water pressure problems is that the water is being obstructed by one or more partially closed shutoff valves. Typically, a home will have one main shutoff valve located inside the house.
If you're suddenly getting low water pressure in one area of the house… ...the supply pipes to that area may either be corroded, leaking or blocked. If all the fixtures in an entire bathroom or the entire kitchen are suddenly getting low water pressure, you can trace the issue to the plumbing pipes.
Your hot water heater has a shut off valve that can become partially closed. Good news about this issue is that it's a very simple fix—twist the valve back to its fully open position and your hot pressure should come roaring back.
If you have a sink in your home where the hot water pressure is low but cold is fine, it can indicate an issue with your water heater. Typically, if your hot water heater is having issues that cause low water pressure when the hot water is running, it won't affect only one faucet in the house.
If the hot water pressure is low, but the cold is fine: You may have sediment and limescale build-up in the pipes or faucet, or it could be caused by a partially closed or restricted shutoff valve.
Your house has a main water valve, usually located near the meter; the valve controls the flow of water into your home's pipes. Find the valve and check to see if it's completely open. Opening a half-shut valve is one of the quickest ways for increasing home water pressure.
The good news is that you can easily replace faucet aerators, clean showerheads to remove limescale, or simply buy new fixtures to replace the defective ones, which can improve your water pressure. However, it is important to know that repairing or replacing faucets and fixtures is only a temporary solution.
Pressure loss can be a serious threat to public health. A reduction or loss of pressure in the distribution system can result in backflow, allowing contaminants to enter drinking water through unprotected cross-connections.
In addition to the mains stop valve outside the home, you'll have one inside. Your internal stop valve is most likely beneath the kitchen sink. Your external stop valve is owned by the water company. If it's open yet the pressure here falls below one bar, it's their responsibility to improve it.
There are many reasons why showers lose water pressure. It can range from old corroded pipe work to gravity fed systems or your balancing pressure valve.
High or low water pressure can damage your pipes, fixtures, or appliances, which costs you more money in the long run.
Water Pressure Readings
Normal water pressure is generally between 40 and 60 PSI. Most homeowners prefer something right in the middle around 50 PSI. Once you measure the water pressure in your house, you can adjust it to a setting that is ideal for all family members and household uses.
Clogged aerators and clogged cartridges are two of the most common causes of low water pressure in a sink. The aerator is the tip of the faucet that the water comes out of, while the cartridge is found underneath the sink handle and enables you to stop and start the flow of water.
Check Your Aerator
If you have especially hard water, aerators become clogged with hard water buildup, a common cause of low water pressure in kitchen fixtures. Clean your aerator for a quick and easy DIY fix. Remove the aerator from the faucet using pliers and a towel (to prevent scratching).
In short, this valve helps alleviate excess pressure from within your water heater, helping prevent potential tank bursts and leaks. A T&P valve can be found on every standard water heater and on some tankless water heaters.
If you notice excessive noises coming from your unit, there's a problem. Two common water heater sounds are rattling and whistling, both of which result from built-up steam that can't escape the unit. If the steam can't escape properly, that means the pressure relief valve isn't working.
Find the spigot closest to your source of water. Make sure all the taps and other water uses are turned off in your house. Now turn on the spigot and see how long it takes to fill the bucket. Dividing the number 60 by the time to fill the bucket will give you the gallons per minute number.
Low water pressure can present itself in various ways, all of which can cause significant inconveniences. Taps may take forever to fill your bathtub, or the showerhead may not spray water efficiently. Either way, your daily activities are slowed down. Sometimes the issue comes from the municipal water supply.
To return to full pressure only takes seconds. Flushing and recirculating takes minutes if you open all the taps, with the exception of tank water heaters.
If you have a combi boiler or unvented system, you're unlikely to experience any issues with low water pressure. However, with a gravity fed system, you may run into problems if you don't buy a shower suitable for your water pressure.