To have a manifold is not necessary and he is correct, it
costs $$$. However, it’s much easier later when you need to do maintenance on
your system. You can simply shut off one zone and work on it, without
disturbing the rest. To answer your question whether you need one is not easy,
what I can say, you don’t need it, but it’s nice to have it.

Not a waste of money, it is functional. However, not completely necessary for operation. Consider it a breaker box for your plumbing. What I have done is two manifolds, one for the hot one for the cold, and had a line run from the manifold to each room. It has come in handy to have. Have not had any pressure problems or hot/cold fluctuations in the showers.

Now some people overdo it in my opinion and do what is called a home run system where each fixture has its own run to the manifold. This is overkill. A lot more water lines and fittings that could leak, also a lot more hot water lines that cause more wasted water and decreased efficiency.

Manifold is best to be located appropriately near everything that uses water. Best designs for houses concerning plumbing have bathrooms, kitchen, laundry near each other (above, below, adjacent) for plumbing purposes both water supply and drain lines.

I would run large (1") lines to each bathroom / kitchen and install a smaller manifolds to service the fixtures.

The ugliest thing is to have all 'home runs' - looks like an impossible spaghetti bowl.

Thanks for the replies. What do you guys think of something like this? http://us.grundfos.com/products/find-product/up-10.html

Personally, I am not a fan of hot water recirc. It just decreases efficiency and increases utility cost. Also, if you don't insulate those water lines very well you are basically making a radiant heat loop to heat your home, which would require more cooling.

Best way to manage hot water is to properly locate the heater and have short runs. It literally takes me 5 seconds to prime the hot water in the morning or when I get home after work, no need for me to have a recirc running all day.

Looks like a decent unit though.

I think the benefit of this unit is that it is programmable. Which means I can set it to run whenever we normally take showers

rmverb,

I have a programmable recirculating pump built into my tankless heater. They are great. We run it for about 3 hours a day. Once in the morning and again in the evening.

Good luck!

I was wondering if it would work with a tankless water heater. Thanks!

Tankless activates at a minimum flow rate, if the pump achieves that it should work.