Radiant and panel rads on single zone?

GettingCold

Hello all-



I need to combine two panel radiators and two radiant floor circuits on the same zone, and I'm wondering how I accommodate the different water temperatures required by each.



The zone is a secondary loop on a primary/secondary system fed by a brand new Lochinvar Knight boiler. The zone has a dedicated circulator.



The radiant area is small, and only requires two loops of about 220 feet each. The panel radiators each have a TRV, and have fittings that allow bypassing if necessary.



Based on my heat loss calculation, the panel radiators will require ~160 degree water, while the radiant will need significantly less. The radiant floor will be Wirsbo's QuickTrak system, which is installed above the subfloor, but below the finished floor.



In researching this problem, I've seen mixing valves used to regulate the supply temperature of the radiant floor. Can I simply add a thermostatic mixing valve to mix some of the cold loop return water back into the supply? (see diagram) Will there still be enough pressure to maintain circulation in the loop?



Thanks for reading!

Ironman

Another circ

You'll need another circ drawing out of the "mix" port of the valve and pumping towards the radiant supply manifold.



I'm skeptical of how well this setup will perform, though.

GettingCold

A better way?

Thanks Ironman...



Is there a preferred way of mixing temperatures on a single zone?

Zman

Lochinvar

The best way to do this is to have the Boiler control the mixing valve.

That way the boiler is always at the lowest temp.

Lochinvar is designed to do this.

Carl

Unknown

nope

Nope, won't work as u drawn... needs own pump and stat.

kcopp

a simpler way....

is to size the panel rad to work at the same temp as the radiant floor. Then run them off the same manifold as the Q trac