Hydro Air

[Greg_D]

Hello,

I have a hydro air system setup in my house where I have two central a/c units for an air handler in my basement near my current oil boiler and an air handler in my attic. What I am looking to do is see what my best option is to install either an inside or outside wood boiler and have it work in conjunction with an oil burner as a backup in case we are away for an extended period of time.

I had initially seen the PSG Max Caddy as an option but I am not sure if this is simply forced hot air where it will not work with my hydro air system. I liked this product initially as I would be able to use only one flu for this combination unit since building a second chimney on the outside of the house is not an option. I have also been looking at outside wood boilers and seeing what thoughts are on those for being able to work in conjunction with my oil burner on the inside for times when we are away.

Our house is 3500 square feet for the main two floors of living area. It would be nice though if I had the option of being able to heat at least part of the basement (and maybe the attached two car garage) at some point down the road. We have an additional flu in the chimney for the fireplace in the living room but it is not possible to put either a wood stove or insert in.

Any thoughts on what might be my best option for this setup? Thanks!

 

[E Yoder]

So my perspective is on tieing in outside wood boilers into these systems.
I probably would pump from the outdoor wood boiler to a flat plate heat exchanger. Another loop from the oil boiler to the flat plate. Use a temp control to switch between the pumped flat plate loop (drawing heat from the outdoor boiler) when it is hot, switching to oil if it drops temp.
Then tie in the hydro air coils off the oil boiler with a thermostat, pump, relays etc.
This way you have auto oil backup.
You could pump the coils and garage heat etc as secondary loops directly off the outdoor boiler lines too, but then the oil wouldn't back them up.
One thought, you'll want to consider the potential for freezing the attic coil during a power outage. I often place the attic coil right behind the cold air return to protect it if it isn't in a conditioned space.

Others could describe indoor wood boilers better than I. There are plenty of options out there for sure.