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My First Retrofitting In-Floor Radiant, Cross Manifold, ViPERT, WiFi Pump, Old School Boiler

watercourse Member Posts: 28
edited February 2023 in Radiant Heating
Hi, I could use some pointers. Could you spare a moment to advise on my first radiant project?

It's also my first time doing a plumbing / heating / boiler related project. It's intimidating yet exciting!

Would you be up for taking a look at my boiler room pictures and advising on the setup?

I'm converting from baseboard heaters to in floor ultrafins. Keeping my hot boiler for now. Maybe switching to a hot air to water heat pump years down the road.

I think I just need to get the boiler plumbed over to the wall where the new manifold will go.

Maybe I should replace and add a few parts?

Any component updates you'd recommend?

What adapters and pipes do I need to get the water to the wall? For example, it looks like the pipe coming off the boiler is 1 1/4" type L copper, and I think the Cross Manifold inlet connections are 1", threaded.

I'm using cold expansion connections wherever PEX/PERT fittings are needed.
Thank you!


  • EzzyT
    EzzyT Member Posts: 1,296
    Was a room to room heat loss analysis done along with radiant design software used to determine that the radiant will be we enough to heat the home?
    Based on the numbers of the Heatloss I would compare that to the current boiler size. You might have a way oversized boiler so in that case might be wise to replace with a properly sized one. I wouldn’t use the ultra fin radiant heat emitters. Reasoning is that you’ll need to operate at a higher temperature then using extruded aluminum plates that screw to the bottom of the subfloor.
    Since your going to do all this work to might as well have it operate at a lower temperature which then would cut your operating cost along with better comfortability.
    Since you said you would be keeping the boiler for now I would just repipe the entire boiler with a Thermatic valve to prevent thermal shock and use a air, dirt magnetic hydro-separator. Plumb primary/secondary piping.

    E-Travis Mechanical LLC
  • hot_rod
    hot_rod Member Posts: 22,258
    It doesn’t cost anything to do a room by room heat load first. You want to assure the system will adequately cover the load.

    The goal should be to heat the rooms with the lowest possible water temperature
    120f or lower would be the target if you plan on a heat pump someday.

    Panel radiators are another retrofit option.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream