Swapping out baseboards for radiant.

riclyo

My first post here

https://forum.heatinghelp.com/discussion/153614/gas-hw-boiler-constantly-cycling-on-cold-days-to-keep-temp

ended up getting the help I needed and figured let’s try again.

Boiler is still running strong now with the split loop and additional radiators put in place to bleed off the excess heat by the oversized boiler.

I want to add an indirect water heater as my gas fired is in the way out and got a deal on a practically brand new ID. While going through re-piping I thought why not do the radiant system I was talked out of when my original system was designed.

Here is my basic hand drawn schematic I was hoping to get some feedback on.

I’ll be adding a DHW loop, keeping a baseboard/radiator loop and adding (2) zones for radiant. I’d like 1 of the 2 zones of radiant to share a thermostat with a baseboard/radiator zone.

For radiant is it better to use the circulators or circulator→ zone valve setup?

I saw different piping diagrams showing 4-way and 3-way valves for lowering the radiant temp I’m really confused on which route to go here.

Also most of my floor joists are 24” OC 2x6 I was thinking of doing 3 runs of 1/2@ Pex on extruded track for what I’d like to call the “colder rooms” and 2 runs for interior or rooms that will still have baseboards/radiators.

Lastly what are the general piping mistakes I need to avoid when doing a project like this.

Jamie Hall

Zone valves aren't really needed on radiant, since it should be always on. That said, however, if your two radiant zones have distinctly different heat loads but similar piping layouts, they will need different floor temperatures — and therefore two separate mixing valves and circulating pumps.