Boiler with Radiant Piping

Home built in 1900 with a newer boiler. They removed all the radiators on the first floor and ran piping between all the floor joists and then put a thin insulation over the piping. The second floor has baseboards. I have never seen it done quite like this before. It looks like it was installed in 2018. Any pros or cons on this install?

Do you like the saddle clamp on the PVC?

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Is that a high efficiency boiler or conventional?

That mixing valve suggests it’s a conventional but if it’s a HE, and they don’t have a hydronic mixing chamber or closely spaced Tees, it probably doesn’t perform all that well.

I don’t see a pump on the primary loop if there is one, just the pump on the zone manifold.

It’s a little facocta but if it works, it works I suppose. I know that’s not how I would have built that system, and the underfloor piping could have been done better, but you really just need to get it up near the floor and it’ll warm the whole area.

Edit: as a note, those two tees are oriented improperly to be closely spaced tees for a HE system. The top one would be ok, but the bottom one needs to be 90 degrees rotated.

Thanks for the info. I think he may have installed all this himself. The owner recently had a stroke so it was hard to get much information about it. I am going to recommend and HVAC profesional to take a look. There is also an issue with the sump pump. The water is dark and stinky and when I operated the pump the water started foaming up. I thought the washer was dumping into the sump pit but it is not. Then they told me they have never had the septic cleaned and are not sure where it is…

I dug through some old emails and found one system I built.

This is how they are supposed to be created, including all the heat loss deltas and such per zone.

You can use a Taco Hsep, crown bimini buddy or closely spaced tees to mix the two loops. This was from 2012, so there are even more options today.

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I’m going to go out on a limb and guess that some mice found an untimely end in the sump pit.

The foaming could be a roached impeller but i’d leave that for a plumber if it didn’t suck it down, oof.

Thanks for the info.

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I haven’t done my first inspection yet and am curious on how you approached this? What did you start looking at first?

Are you referring to the heating system?

Old school, radiant heat pipes underneath subflooring and finished floors, between floor joists. I can not see good radiant energy transfer that way. Typically atop flooring with radiant piping woven in grooved insulation or held in place with clips atop ridged foam board.
As for the cast iron hot water radiators. Flow will be controlled by circulation pump and supply branches on the manifold delivering hot water.

Then you would be very surprised how well it works. You can run any pex type tubing near the flooring and it will heat it. This is through 3/4 sub floor and 3/4 hardwood.

We typically would do runs of supply piping near front entrance doors to help with snow melt. I’m not talking about radiant flooring. That’s a whole nother issue. I’m talking about running pipes (typically fostapex) straight down the space between the joists right up to the entrance and then continuing at a 90 towards the fin tubes under the windows.

We suspend the tubes down by 1 inch from the floor to avoid any flooring cleats that might get shot during a flooring install.

It’s a poor man’s radiant floor and it works with nothing other than planning on your supply runs. It was one of the things people always commented on. “We love how you put radiant underfloor heating by the door! The Dog loves to sleep there and it stays dry!”. LOL.