Hydronic with Fan Coil?

[Jim Katen]

This is 1920 very large 3-story house with a single boiler in the basement and baseboard radiators in each room. The radiant portion of this system looks perfectly typical. The building has no air conditioning. 

In addition to the radiators, the boiler also sends hot water to an old fan coil unit in the basement, with ducts leading some of the 1st floor rooms and some of the 3rd floor rooms. 

This is not a normal configuration in my area. I had thought that perhaps the designer was trying to defeat stratification of hot air, but that seems unlikely. 

Is this common in other areas? Any idea why this would be done? 

[Marc]

Someone griped about cold rooms in an older home, so they added the fan coil to further tap into the boiler capacity?

[Rob Amaral]

Were there remnants of 'fresh-air intake ducts' at the perimeter basement level?   We do have some trillionaire-1890's houses around Boston that have remnants of 1st floor level 'fresh-air intake vents' (louvered/screened) at the exterior that bring in fresh air that wafts in over steam radiators placed in 'boxes' just under the first floor....   they were really into 'fresh air' this, 'fresh-air that' back then... 

I've never seen (yet) what you describe for hydronic..    (Was the system a former 'gravity' circulating water-system?)

 

[Jim Katen]

I doubt that there were problems with cold rooms. The radiators, if anything, look to be oversized for the rooms. And the ducts are centrally located in the house, nowhere near the outside rooms. 

There were no remnants of outdoor air ducts. If there were, they'd have been obvious. 

The pipes look much too small to have been used with a gravity system, but I see so few, it's hard to say. Weren't gravity hot water systems out of date by 1920? 

[Rob Amaral]

I've seen 'gravity' (no circulator) water-systems from 1920 around Boston for sure...