Low water pressure

[Sophia0818]

Good morning we just had a new hot water heater installed. Our old one was 18 years old and it worked great. Our water pressure was good and everything. It just was old after they installed the new one we paid them. I waited about an hour turn the water on in the kitchen And the water pressure was really low. So I sent the company an email letting them know that somethings not right. Our water pressure is real low. They send the same guy back out the next day and he’s telling me it has nothing to do with what they did. It’s just a fluke, but I don’t believe that Because our pressure was excellent until they installed the new hot water heater so I don’t know what to do plus they installed the new expansion tank sitting on the back of our hot water heater laying on its side. Our other one was on the cold side and it was upright. I just found that to be a little weird but again I’m not a hot water heater installer.

 

[MicEd69]

First, it's a "water heater" not a "hot water heater". Hot water doesn't need to be heated. A little plumber humor there, sorry.

When you say your water pressure is low, are you only talking about the hot water pressure, or the water pressure on the cold side as well and all over your house? If it lower on your cold-water lines as well, installing a new water heater will not reduce the cold-water pressure in and of itself. Depending on how they had to turn of the water in your house, I suppose something could have happened like some mineral buildup breaking loose causing your PRV (pressure regulator valve) to stick, assuming you have one.

How are you determining your water pressure is lower? I assume the flow rate from your faucets, shower, etc.

When you say, "...they installed the new expansion tank sitting on the back of our hot water heater laying on its side. Our other one was on the cold side and it was upright...", are you saying they put the expansion tank horizontally and on the hot water line? Those tanks are best installed vertically but can be installed horizontally. But they are rarely installed on the hot water line from the water heater.

 

[BlueSkyHigh]

This caused me to check our installation of the expansion tank. Horizontal on the cold side.