I have a floor plan, and would like to have some input on how many zones I should have. It is a two bedroom, two bath, with a study, kitchen/living room.

I've been thinking that there should be six zones. All rooms separate except for kitchen and living room, since they share the same large open space.

I'd like to hear what may be the pro's or con's or improvement of this configuration of zones.



Also, I'm looking for recommendations on where to get a tube layout. And also where the best place to get the PEX is. I've used Pexsupply in the past.

Thanks!

Multiple zones are OK so long as folks occupying the various rooms have disparate temperature preferences. It may not be OK if it is because you want to shut off the heat in these rooms to save energy when these rooms are occasionally unoccupied. A hydronically heated room will take many hours to come up to temperature.

If you buy your Pex from BlueRidge.com,  their price for tubing is in line with others, they ship for free, and they will do your layout for either a small fee or gratis.

The time to temp can be very quick or quite slow, depending the thermal mass of the radiation. Slabs would be slow, but panel radiators or WarmBoard type systems would be relatively speedy.

A bigger system-issue with microzoning is how to control the micro-LOADs in such a way that it doesn't short-cycle the boiler into an early grave or gross-inefficiency. A mod con with a 20K min-mod is going to have issues running efficiency with 6 separate randomly timed calls for heat, 5 of which might have a sub-1K load on a cool March afternoon. Using a central buffer tank as the hydraulic separator in a primary/secondary is one approach, but there are others, each with good & bad points. If the zones are all high-mass (5 inch slabs or something) they'll be pretty much self-buffering from a short-cycling point of view, but you could still be doubling or tripling the number of burn cycles during the shoulder seasons.