Hot water takes long time to reach one faucet, all others ok

We have an electric Kenmore Power Miser 9 (40 gal) water heater installed in our laundry/utility room. In the very next room is our second bathroom, a 3pc: sink, toilet, shower. For some reason the water feed to the "hot" sink faucet takes a long time to get hot. It runs cold or room temp for what feels like a minute or two before starting to heat up and eventually reach proper hot temperature. The shower (uses lever-style faucet) is fine.

The bathroom was here before we moved in so we don't know if the plumbing was routed after the house was already completed or roughed-in during construction. Any ideas on what I could check or what might cause this? Thanks.

Perhaps the piping runs through a concrete slab acting as a thermal mass. If it goes slowly from cold to tepid to warm to hot, that suggests heat loss to a thermal mass.

It could be that the lavatory is further from the HWT on 3/4" piping and the lower flow rate of the lav takes longer to purge the line. The shower would likely have a faster flow rate and may be closer to the HWT.

For some reason., they may have taken the hot water from that lav off at a more distant location. Hard to know that now. A simple retrofit recirc like the Grundfos Comfort system, will take care of it.

The shower has a higher flow rate than the sink, so it WILL get hot faster. Why it takes longer is a function of how the piping was installed, which might be figured out with a little bit of detective work.

jimbo said:

For some reason., they may have taken the hot water from that lav off at a more distant location. Hard to know that now. A simple retrofit recirc like the Grundfos Comfort system, will take care of it.

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Hey, I sort of have the same thing going. I just pulled my sidearm off the boiler and went back to electric. I always had to knit a pair of sox waiting for a shower even though the sinks right next to it were almost instant. This time i ran a whole new line so it starts near the shower and I get nearly instant hot water. Only problem is that now it takes the same long while to get hot to the kitchen sink. I can live with it but how about this? Just plumb another line over to the nearest part of the line that feeds the sink and tie in there? Any reason not to do that?????