Adding Recirculation

[MacMan34]

Hey all,

I have a Navien 240-A unit that was recently installed in my home.

I am debating putting in a Grundfos valve or 2, or adding a recirculation line in the crawlspace to the furthest bathroom on the main line (about a 25 ft run)

The upstairs bathrooms are on branches from the main line, with fairly long runs from the line to the sinks as the main line is in the crawlspace.

So my question: will putting a ~25ft recirculation loop under the house help us get hot water upstairs faster?

Or, can I put this line in AND install a Grundfos valve in the master bathroom on my wife's sink? (her main complaint with the new water heater is lack of hot water in her sink)

I am not willing, or able, to install a true whole house recirculation line as I do not want to tear up walls.

Any advice or tips would be appreciated.

Thank you.

j

 

[Jadnashua]

First off, read the owner's manual. Some tankless systems will void the warranty if you use a recirculation system. If it is possible with yours, it must be done in a certain way. Some of them actually have a small tank inside, but it needs to be switched on to function.

One alternative, if you have a little space, is to put a small tank near or in the furthest room where you are having to wait for the hot water. You'll have hot water there, regardless of the flow rate (like trying to get warm water in the sink that might not trigger the tankless to turn on) and once the water from the tankless arrives, it is buffered by the small tank. A small electric one is pretty well insulated and it wouldn't need to be huge, maybe 5-gallons or so. You'd run the tankless into the cold water inlet of the small tank.