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How To Deal With Low Hot Water Pressure In Your Home

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If you have recently moved into a home and have dealt with low water pressure coming from your hot water lines, then you may want to think about investigating the issue. This is especially concerning if the problem exists with the hot water pipes alone. Keep reading to learn what you should do to investigate the problem and also what should happen if you find an issue.

Look At The Piping

Most water heaters are installed by professional contractors, but this is not always the case. If a professional installation was not completed, then the wrong pipes may have been used to create both the cold water inlet and the hot water outlet pipes. For most installations, these pipes are sectioned off from the main water lines. The inlet pipe comes down into the water heater, and the outlet pipe forces the water up and away from the appliance. This creates two angled tees on the top of the tank. 

Since water must be pulled up and out of the tank to supply your home with hot water, water pressure can be lost due to both gravity and friction. The result is low water pressure. The smaller the pipes going in and out of the tank, the lower the water pressure will be. Water supply pipes come in a variety of different diameters, with the thickest pipes one inch in size and the smallest about one-half inch. One inch pipes are common for main supply lines, and the one-half inch ones attach to your sinks and other fixtures.

Between the one and one-half inch pipes will sit three-quarter inch ones. These three-quarter inch pipes should run both to and from your water heater. However, some inexperienced individuals will install one-half inch varieties instead. This will significantly lower your hot water pressure. You should check the size of the pipes to see if this is the case. You can use a ruler to measure the thickness of the pipes and then use a pipe measurement chart to match the appropriate dimension. For example, a three-quarter inch PVC pipe is 3.25 inches wide. If the pipe is thinner than this, then it is likely a one-half inch variety. If the pipe is one-half inch, then speak with a contractor about switching it for a larger diameter one.

Inspect The Anode

If the hot water heater is an older model, then it may be time to switch out the sacrificial anode. This part of the water heater stops exposed metal inside the tank from corroding. When the anode starts to wear away, larger chunks of it can break off and clog the hot water outlet pipe. Also, when the anode is no longer intact, the water heater can corrode. Corrosion can end up moving up through the outlet pipe as well.

Inspect the anode to see if it is still in good condition. The sacrificial anode screws into the top of the water heater, so look for a metal protrusion that can be screwed off. Release it and pull the rod out. Sacrificial anodes have a long, slender wire in the middle that will be seen if it has corroded. If you see the wire, then replace it.

Once the anode is replaced, use the drain on the bottom of the water heater to release corroded material from the appliance. Run your hot water afterwards to see if the pressure increases. You may see some rust coming from the tap when you do this, since debris has been stirred up during the repair. This is normal.

If the water pressure does not increase, then the outlet pipe may still be clogged with debris. You can pour an additive in the tank to dissolve the corroded material. Acids will dissolve rust, so opt for an acidic substance that is safe for consumption, like vinegar, lemon juice, or seltzer water. Pour a gallon of your additive in the tank using the anode opening and allow the water to mix with it. Wait about 15 minutes and then run your hot water for 20 minutes. The corrosion should dissolve and water pressure should increase. 

If you continue to have problems, talk with a professional water heater service or visit websites like http://www.rbincorporated.com/ for more information.