Recirc pump above or below water heater

Rick Sass

I've looked at two different pump manufacturers websites and one make a point of installing the pump below the water line of the water heater so that the pump flow is always upward or directly horizontal and not downward. The other pump manufacturer says go ahead and put the pump above the water heater because the recirc loop is always pressurized. Can someone explain this to me and can I put the recirc pump above the water heater?

Thanx,
Rick

Brad White_9

In a closed system there is no waterline.

One can argue that a domestic hot water system is "open" but for practical purposes it should be under pressure (50-80 psig or so) sufficient that it will behave like a closed system.

My recirc pump is above the heater and it never complains. In fact I have never seen one below the heater although I cannot see why that would not work either.