Hi everyone,

I recently had my HVAC designed and I have a few questions regarding how to set up a multi-zone controller with a single HVAC unit.

My design came back with 3 zones (1 per floor, including basement). I was planning to use an EcoBee3 for the thermostat, but I'm trying to figure out how that would tie into a zone controller and how the zone controller actually works.

Which piece communicates with the furnace? Do I need more than 1 thermostat since the ecobee3 can have multiple remote sensors? What dampers and controller do you recommend?

I'd provide significant bypass for each damper - so there is sufficient flow for the furnace even when only the smallest zone is calling for heat. Ie, think of zoning as providing a fairly small adjustment to the amount of heat being delivered, not an on/off control.

Without looking, my guess is that you need 3 of the thermostats for 3 zones. The furnace needs an on signal when any of the zones are calling for heat.

Thanks for the response. My understanding is that bypass ducts should not be used. I'm basing that solely on http://www.energyvanguard.com/blog-building-science-HERS-BPI/bid/44187/Navigating-the-Twilight-Zone-The-Hidden-Flaw-in-a-Zoned-Duct-System



even still, do the returns get dampers too? I assumed they would always be open.



I assumed that the zone controller would be the interface to the HVAC. Is that not the case? I guess that's part of my non-understanding is how each component relates to the others and which pieces provide each signal.

They are talking about a bypass from the supply to the return, not a stop on the zone damper that allows air to flow through it even when it is "closed". Pulling from a return duct while a supply duct is off (or even restricted) in a closed door room will depressurize it - causing high infiltration.

I gotcha. Sorry I misunderstood what you meant originally. Do you know of a brand of dampers and controller that has these features?

Btw, in all my searches all I can find is a Honeywell and Zonefirst system. Are these the most common? Are there other 'good' ones out there?