PV wrote:

I've timed it. For each faucet, it takes 3-4 minutes before the water
that comes out is warm. It is an excruciating long time to wait for
warm water, especially now that it is winter. In the summer, I didn't
mind washing my hands in cold water.

I'm in NC, my hot water heater uses gas and is located in the attic of
my 2-story house, not integrated.

snipped

How about trying this check and telling us the results:

Tomorrow morning, before anyone opens a hot water faucet in the house, clamber up to where the hot water heater is and
grab the outlet pipe a couple of feet from the heater.

Then yell down to SWMBO to open a hot water tap somewhere and then see how the pipe feels.

If it was warm and cools down, then there's a problem with the heater.

Might be that the installer screwed up and plumbed the inlet and outlet reversed so it's feeding the water out through
the dip tube from the bottom of the tank where the cooler water sits, instead of from the top, where the heated water
rises to. That's not hard to do if you don't pay attention to the "Hot and Cold" markings on the tank.

If the pipe gets hot right away and stays hot for the several minutes it takes for the water at the tap to get hot,
then as most of the others have said, it's a piping length/volume problem, best solved by using one of those motorized
recirculating pmp thingies and some additional piping, or selling the house. (Ducking...)

Happy New Year,

--
Jeff Wisnia (W1BSV + Brass Rat '57 EE)

http://home.comcast.net/~jwisnia18/jeff/

"If you can keep smiling when things go wrong, you've thought of someone to place the blame on."