DHW gravity recirculation

andy_21

We are having a new heating system install as I type, Knight 105 w/ 80 gal Super Store Ultra.
On My old hot water heater instead of a pump on the recirculating line, there was a swing gate check valve w/ a 1/4" hole drilled into the gate, piped into a tee @ the bottom drain. This set up always a worked in having almost instant hot water @ the furthest fixture. On the new tank the cold inlet is @ the bottom. Can they still use the same piping set up as my old style tank or must it be pumped?

Also is there any time the condensate water should not be run thru a neutralizing set up, before pumped into sewer system.
Thanks

Mike T., Swampeast MO

Try first. A circulator can be added if needed. If so, look for the tiniest circulator you can find as the needed flow will be in gallons per hour not minutes.

martin

Recic.

This should work fine as long as you have slope, we have done it many times.

andy_21

Thanks for the input, but I was wondering where they would hook the check valve to, the cold water intake, recirc intake?
Thanks

Mike T., Swampeast MO

The cold water intake will become the recirculation intake. I'd install a tee very near the intake. Use the branch for the fresh water then install the check valve a reasonable distance (say at least 4 pipe diameters) away from the tee. In other words, in this order: check valve, tee, tank.