Hot water recirculating pump issue

bluesmokey

Bought this house about a year ago. Hot water is fast in all but one bathroom sink. It takes time for the hot water to arrive. What would cause hot water to be available within 15 seconds to all of the house but this one sink?

EdTheHeaterMan

The pipe diameter and amount of distance the water needs to travel from the hot water source to the hot water destination. . If you can get a piece of 3/8" PEX to run from that farthest (Problem) hot water fixture back to the water heater, then you can use a Recirc Pump that you can mount under the problem sink. When you turn on the light for that room, then the pump motor will run to get the hot water there. By the time you are ready to use the hot water, there will be no wait time. When you finish using that room and turn the light out, the pump can stop recirculating the hot water.

EdTheHeaterMan

But if the problem sink is close to the other fixtures, then there may be a cross connection in the hot water piping and the water needs to take a round about route to that faucet. More info is needed to tell for sure.

Larry Weingarten

Hi, One other thing I'd check is to see if there might be a crossover between hot and cold. If there is, this would affect how quickly you get hot water, and how hot it is. The test is simply to turn off the cold input to your water heater and open a hot tap. It should quit running in seconds. If not, cold is getting into the hot side someplace.

Yours, Larry

ps, A question: Is this one sink a long ways from any other hot plumbing?

retiredguy

I have a similar system in my home and I piped all the returns with 1/2" copper into a 3/4" manifold and added a very small bronze pump and timer. The pump was the smallest B&G I could buy. It has worked for 20+ years and I get hot water within 5 seconds at all faucets. You do not show a pump in your drawing and if you are depending on gravity flow the hot return may be following the path of least resistance and flowing to the farthest bath.

bluesmokey

Thanks for the replies. This particular bathroom sink is very close to the hot water heater. As a matter of fact it is the closest than any other in the house. I am going to try what Larry stated above and see what happens. Thank you all.

EdTheHeaterMan

bluesmokey said:

Thanks for the replies. This particular bathroom sink is very close to the hot water heater. As a matter of fact it is the closest than any other in the house. I am going to try what Larry stated above and see what happens. Thank you all.

That is a great idea. If it is that close then it ain't water volume of a long run of pipe.