Combining Radiant Floor with Hydro Air

tflash09

Hello all,

I am seeking advice for new construction in CT.  (1200 sq foot Cape style modular, 1 floor with walk up attic to be finished at a later time)  44,000 btu heat loss

I would like to go with Radiant Floor heating off of an effiicient gas boiler and add A/C.  As I will have duct work for the A/C, would it be efficient (or make sense) to add hydro air to utilize that duct work for a second heat call.  I would most likely utilize the duct work for heat for the upstairs at a later date.

I was told by a hot air furnce guy that it would be "dumb" as I would be installing two systems. everyone has their opinions, so here I am.

Any advice on how to put this system together would be greatly appreciated.

Jack

I would suggest

ThaT you do the radiant but eliminate the ductwork. Better, imho, to put in an inverter mini-split heat pump for cooling and shoulder season heating. That is an excellent combo that will deliver great comfort.

tflash09

mini splits

Thanks Jack,

I'll lool into it.  I assume you would need to put multiple units in to cool the various rooms?

Unknown

Combining Radiant Floor with Hydro Air

Radiant in a basement is awesome - at least 20% more efficient than blowing down hot air from a ducted system, vastly improved comfort (warm floors), no wasted space for ducts and quieter.  I would also suggest the basement would be drier (less chance of mould formation).  OK, let's throw in a couple of hot water towel warmers too (my opinion an often overlooked option of HW heating over forced air).



I looked for application drawings for combo systems but unfortunately all I could find was radiant panel/re-heat fan coil/indirect DHW system drawing (by Siggy).  Note this system is designed around an ECM circ - if you use a constant speed circ you might want to consider by-pass loop and wiring a control circuit to shut the circ off if no flow demand (this stuff is NOT required with ECM circs).  Caution on temps and boiler types - radiant is low temp, hydro air might be high temp (or higher temp than the radiant) and the boiler type will have say in it's temp as well (condensing vs non-condensing).



The system drawing is attached (I have others if any of you Wallies want).

Dave Springer

Hydro air with radiant

We've been designing systems for years using heating coils with radiant systems.  It works fine at low temperatures as long as you size the coil correctly - no need to complicate it with dual temperatures unless the loads on the coil are very high. The coil in my house handles forced air heating for the second floor, and cooling for the entire house by running chilled water through the coil in summer. 

tflash09

hydro air w/radiant

Thank you all for your comments,



In regards to the Hydro Air,  are the high velocity systems a good option to go with if utilizing radiant floor panels for heat?   This is new construction (modular)  and not a retro-fit.



Thanks,



Ryan

Dave Springer

High velocity ducts

Not if you care about fan energy.  High velocity systems use a lot and should only be used where there isn't adequate room for ducts sized per ACCA Manual D.