Technical > Home Improvement > Any Redytemp hot water recirculator pump experiences?

I do not intend to have a dedicated pipe to return to the water heater and intend to have it use the cold water pipe for return. But if I read convincing opinions to do dedicated return, I am open to that.

I would suggest you go with running a dedicated 1/2" return line with a simple gravity swing-check valve in the return. Tee the new hot return back into the cold supply, anywhere near the tank. Thermal convection alone is usually sufficient to maintain a constant circulation, chances are you may not even need a pump.

I have mine set up this way and it works like a charm without a pump. Make sure to provide a means to manually vent any trapped air in the return (one time) or else it won't be able to work on gravity. A stop & waste ball valve works fine for this.

Worst case scenario: if the gravity solution fails, then go ahead install a circulating pump, operating it with either a thermostat or a timer. The pump can go in anywhere; supply, return, doesn't matter.

Be sure to insulate the supply and return lines in any event.

While it is copper from the water heater to the sink, I don't see any reason why PEX would not be sufficient for the dedicated return run.

I read one suggestion to use the water heater's sediment drain as the return connection while adapting it to also still allow the tank to be drained if required. The theory is that the returning water when the pump is active will swirl the water at the bottom of the tank similar to how the mechanical "roto swirl" tanks work. Any comments on that idea? (This water heater is less than 3 years old and I do open the drain every three months to try to remove any sediment (which I have yet to see with an eyeball)).

That's exactly how ours is set up including the PEX. It works really well with no problems. It's a really does seem to reduce the amount of sediment in the tank.

PEX is fine to use. You could tie into the drain but it's easier to tee the recirculation return piping into the tank cold supply. The water flow will be directed to the bottom of the tank through the internal dip tube.
Don't forget to install a swing check valve in the return piping to prevent back flow during a hot water draw.

We considered installing a dedicated return line but figured we didn't need 120 degree water instantly coming out our taps due to concerns of scalding and the kids, that and the higher energy waste involved compared to using our cold line for the return.

In response to ttiiggy, the only way the cold water pipes could get full of hot water would be if the pump ran beyond the temperature cut-off setting we selected. I think your talking about systems that use thermostatic valves which get stuck open, but I've only found those in other hot water circulators and not the Redytemp. The main reason they use solenoid valves in their systems were to prevent the problem you described. We've had our Redytemp for 6-7 years now without any problems. If we ever do move it will probably be one of the first things the wife packs, she just loves it.

We are about to begin a kitchen remodel. One of the things I want is to put in a a hot water recirculator pump because the kitchen is the furthest sink from the water heater tank.

A significant benefit that the pump solution brought to the table is that the master bath will get benefit from the same pump like the kitchen will since the master bath tees off of the same hot water pipe on its way to the kitchen.

My plan with this unit would be to also have an on-demand switch (doorbell style hidden beneath a cabinet next to the kitchen sink).

You might want to consider an occupancy sensor there are inexpensive and that way if there is motion in the kitchen the hot water line will remain charged, drop another wired in parallel in the bath and no buttons to push or timers to turn need be remembered.

Wayne