Hot water recirc systems appears installed wrong but works

tset

My new-to-me instant hot water system appears to have a Goulds recirc pump which pulls from two dedicated return lines that pull from a master bath sink and the kitchen sink. The return lines attach to recirc pump at the water heater cold water input.

I can't see any other components to the instant hot water system. House is slab with plumbing in the slab.

All fixtures in the house have quick hot water.

But, both sinks with the dedicated return lines have the return lines tee'd into the cold side!

Anyone know what is going on here?

Regards, TS

JUGHNE

Sounds right, there may be a check valve on the cold water inlet?

Some method to control the pump?

Pictures showing all at the tank and pump would be good.

tset

Hmm, the pump has a variable speed setting. But with no valves connecting hot to the dedicated return at the fixtures, how does recirculating the cold water accomplish anything? (Yet it apparently does.) Will try to get pix.

STEVEusaPA

It's right. Seems wrong but it's probably right.

hot_rod

Not sure what you mean by return lines tee into cold?  At the hw tank?

that is where the returns would tee in to push hot out the top of the tank and down to the fixtures

Larry Weingarten

Hi, A sketch of the plumbing would help if photos can't do it. Is your cold water still cold, or does it get warm when the pump runs?

Yours, Larry

tset

yes, that's my point, the dedicated return lines tee into the cold lines at two of the distant sinks. There appears to be no way for the hot circuits to flow back to the hw tank. I cannot find/see any temperature controlled or check valves anywhere at the fixtures. But they must be there? Hidden under sink cabinet floor? I understand that electricians and plumbers do not "hide" junctions and active devices?

ChrisJ

I can't see anything in the kitchen picture but going by your bathroom picture and description I have no idea how that could do anything as far as hot water recirculation.

Seems like it's circulating your cold water to me.......

Which makes me think it doesn't work.


I'm not sure if it matters but...........do you have electronic faucets by any chance?

hot_rod

Sort if looks like a frost free hose bib connected to the cold line under the sink ?

JUGHNE

Could the H & C supplies be reversed under the sinks?
Then it might make sense.

There is a check valve at the pump at the WH.

mattmia2

Or both those pipes sticking out the wall are hose bibs and the recirculation line connects under the cabinet or floor.

hot_rod

Those circulators tend to get air locked when mounted up high on the tank like that 

The installation manual cautions against having it at the top if the tank

Id like to see an air vent where the expansion tank is connected also.

tset

Ah, you two guys are correct, those two lines do go to exterior hose bibs. So the recirc pump is pulling from something else, maybe there are valves at each fixture that I cannot see. Seems strange that the valves are hidden/hard to get to. Bad practice? I am in northwest Arkansas.

mattmia2

There doesn't need to be a valve, just a tee that connects to the recirculaiton line.

JUGHNE

Do you have a basement, look under those sinks for a tee cut into the hot lines.

Larry Weingarten

Hi, You might get some useful clues by keeping the pump off overnight and then have someone turn it on while you run around and feel the temperatures of the pipes and see if, or what gets hot, and when. That might help all of us to make sense of things.

Yours, Larry

SummitMechanic

Your connection at the hot line is most likely in the floor or in the wall since those taps you are seeing are outside hose bibs. The only 2 issues i see with your recirc connections on the water heater itself are that: 1. The pump is orientated horizontally which will effect the flow rate and life span of the pump, and less importantly: 2. There is no way to isolate and purge your recirc line of air from the room itself. I wouldn't be too concerned about either, but might be a thing to fix when it comes time to replace the pump down the road.