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Hydro Air setup limitations

psciotti | Posted in General Questions on

Hello… I have a coastal home in MA needing a new heating system and want to include AC. Current setup is no AC and hot water baseboard. I’m interested in hydro air system because we have some setup issues. 
Home is 1900sf cape with 400sf kitchen/pantry/mudroom additon being added to left side. There is a  finished basement between the main home and addition with 7′ ceilings. There is no way to run ducts for forced hot air and mini splitting the entire home is tough because of lower ceilings, wall space, aesthtics. 

Question is…if the hydro air boiler is in mech room (right side of main home basement) can just the 1in (or so) water line run thru the finished basement ceiling to addition and then add the air handler off that water line with flex ducts to floor registers for the left side addition? Is there a max length that hot water from boiler can travel before it’s too cold for the air handler to make heat (It would be about 40′ of pipe to new additon). Can this same setup be run vertically to another air handler on 2nd floor of main house to heat/cooling bedrooms?

It’s a large expense and I’m not confident the local contractors have a thorough understanding of Hydro air…..thank you!

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  1. paul_wiedefeld | | #1

    I don’t think there are any issues here. The water lines can always be insulated too. The question that jumps out is why hydro air at all for this application? If you’re installing 2 AC units, the cost difference between this and 2 heat pumps is slim.

  2. Expert Member
    PETER Engle | | #2

    You should probably run a dedicated line to the hydro-air air handler. The dynamics of this and the new addition will be completely different than the old part of the house. The piping is sized for the demands of the hydro air coil. Insulate the pipes and you will have no problem with the length of the run. You can run a coil coil in the same air handler to get AC in the addition, but how do you plan to get AC in the old house?

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