Time with HW reaching top floor

zepfan

Is there anything that can be done in a house that does not have a hot water recirculation line to decrease the amount of time it takes to get hot water to the top floor faucets? The house is four stories, built in 1996, and has roughly 4000 ft2. The new 75 gallon gas water heater is located in a conditioned basement. Once that water gets hot to the top floor the homeowner says there is plenty of it, and just takes about three minutes of running water to do so. Any suggestions would be much appreciated. thanks to all.

nicholas bonham-carter

How long does it take for the outlet pipe of the hot water heater to get hot? After that, how much longer to hot water at the tap?
I can't believe that it would take 3 minutes for the water to get up to the top floor.--NBC

Jamie Hall

Three minutes does seem a bit much -- but I can believe that it surely seems like it, when you're waiting to take a shower or trying to wash your hands. I should time it in this place.

That said, short of installing recirculation lines -- which work splendidly well, but are energy hogs and are a bear to put in if they weren't done in the first place -- the only thing which I know of which will help is to insulate the dickens out of all the hot water feed lines. If there are fairly long runs in the basement, however, you could put pumped recirculation on those -- that would help some.

L Thiesen

I have used the Grundfoss Comfort System in these situations with good results. It does not require a return line, just use the existing water lines.

hot_rod

If the pipes are not insulated it will cost $$ to run a recirc constantly. there are some retro fit systems that turn on when DHW is needed.

3 minutes is not un-believable with large pipe sizes and low pressure especially.

Tankless water heaters also add to the "wait" time.

Dave H_2

ZepFan,

Use a "CrossOver" valve and a smart timer based circulator. You don't need dedicated return recirculation lines, it uses the cold water supply as a return line back to the water heater. Simple retrofit application and more than one valve can be used with one circulator.
The circulator can also run based upon a schedule, but it learns your schedule must like the Nest thermostat learns to create a heating schedule based upon when your home. This way the electrical costs to operate will be very minimal, say in the range of 6-10 dollars a year.
taco-hvac.com/products/systems/instant_hot_water/hotlinkplus/index.html

Jamie Hall

Thank you, @Dave H ! Hadn't seen that gadget. Learn something every day.

JUGHNE

Often on a tall vertical section of hot water pipe it would stay hot by the gravity effect of water temp. The outer section of pipe cools and that water flows down, the center hot column of water is gravitating upward, hits the top and starts it flow down on the outer surface of pipe.
This is evident in hot water heater heating, especially a converted gravity system. 2nd floor pipes heat with valves off even after pump is off.

There must be some horizontal piping here that might dip down and prevent that passive gravity flow. If it were obvious in the basement then something could be done. But otherwise not.

zepfan

Thanks to all, I am going to look into the system that Dave H suggested. take care

zepfan

Dave H thanks for the suggestion and link for the Hot Link Plus system. I am going to install that. Sounds like a great idea.
Thanks to all

Dave H_2

My pleasure all,
ZepFan, when you're done with the install, let us know how it works out for you.

Enjoy