Thermostat suggestions for radiant + HVAC + multiple zones

I'm building a new home with 3 floors. Each has radiant heating and forced air HVAC. The layout looks like this:

Basement: 3 radiant heating zones + 1 HV (no AC)

1st floor: 3 radiant heating zones + 1 HVAC 2nd floor: 4 radiant heating zones + 1 HVAC

I'm thinking about using a 2 stage thermostat for HVAC+radiant on the basement and 2nd floor, for a total of 11 thermostats:

Basement: 2x single stage (radiant) 1x two-stage thermostat (radiant + HV)

1st floor: 3x single stage thermostats (radiant) 1x single stage + 2 sensors (HVAC)

2nd floor: 3x single stage thermostats (radiant) 1x two stage thermostat (radiant + HVAC)

It seemed like lot of thermostats, but apparently multiple zones with radiant heating is easy to do. The HVAC installer didn't feel comfortable with multiple zones, so there's a single HVAC system per floor (basement is just HV). This works since we won't be using AC much and the forced air heating primarily to assist the slower radiant heating.

We'd like to have some central control, so I'm considering AprilAire, Prolliphix, HAI, and RCS. Here's what I've gotten so far from reading the archives:

RCS: A little more complicated for our installers to wire because the RCS control units and network are located by the HVAC system and in our case, the locations are split between the basement and attic (HVAC), and garage (radiant).

Proliphix: Might be an overkill and the controllers are a bit expensive. Plus I don't read much about these. However, it does seem easy to wire.

HAI and AprilAire: Architecturally, these look very similar and seem like they would both work. The HAI looks a little homely, and the AprilAire is a little big.

Are my observations on target, and are there other options or considerations we should include in our decision?

Reply to
chi
Loading thread data ...

When you hire someone to design a system, go with what they say. When you want something different done, submit your request in writing to the designer. If there's a physical reason why it's not possible, they should be able to tell you. Be prepared to pay a lot more for what may in fact end up to be little or no additional benefit.

Reply to
Bob

What are the HVAC contractors recommendations?? He is there and can *see*, and knows the exact requirements of the system. FWIW, I would consider talking to your local Honewell controls rep.

Reply to
Noon-Air

I have used HAI thermostats in two homes (both multi-zone HVAC systems) and have had nothing but praise for them. I'm not quite sure why you call them "homely" -- they don't have many buttons but they are very feature-rich and focus on making them look clean and simple to use.

You might consider going with your contractor's recommendation for the "backend" equipment, meaning the zone controllers, etc. Then if you went with HAI thermostats and a HAI Omni system, you would have the ability to seamlessly control and integrate every zone with a very powerful home automation / security system.

If you didn't want to hook everything up at construction time, you could just add a 22/4 or cat-5 wire at each thermostat location and wire them all to a wiring closet where the HAI Omni system will be located. That way the contractor could install the HAI thermostats (they will work perfectly fine as independant devices) and later you can network / centrally control them.

Having them integrated into a home automation / security system opens you to so many options, such as adjusting the settings per zone based on occupancy sensors, security settings, vacation settings, any kind of complex schedule, remote control via phone / internet, etc.

For more information on HAI, you can go to the manufacturer's site

formatting link
and there is also a great discussion board and a KB with some application and installation notes on Worthington's site
formatting link

Good luck, Kurt

Reply to
Kurt Delaney

Tn4.

formatting link

Reply to
HeatMan

The forced air HVAC contractor is not sophisticated. He doesn't know what zones are, much less automation or radiant heating (I asked, "What's the work needed to set up 2 zones using some dampeners?" His response, "What's a zone and what's a dampener?").

The radiant heating installers prefer a single stage at each location. They are willing to install for 2 stage, but only if I insist. They pointed out various web sites for thermostat manufacturers (aprilaire, tekmar, and luxpro) and that was all I got.

I notice that Tekmar specializes in hydronic/radiant heating controls. Anyone have any experience with their controls in radiant heating applications? They claim a thermostat controlling a hybrid system should support pulse width modulation.

Kurt: I didn't mean to sound overly negative about the HAI appearance. Just not quite as clean looking to my eyes as, say, the RCS line.

Reply to
chi

How far along are you in the building process? Do you have a general contractor, or are you the GC?

Reply to
Bob

Don't get me started on the general contractor. When I asked him about zones, he said they were only used for commercial purposes. At my insistance, he brought in someone who he said was an expert. The "expert" said it wasn't possible to use zones in most locations because it would create too much air flow.

How an "expert" in zone systems would not even know about bypasses is beyond me....

Reply to
chi

Sounds like you need to be very involved with the design of the system. It is too bad the contractor isn't much help there.

I guess I was just trying to make a point about not necessarily having to tie the zone controller system with the thermostats, like you do with some systems. I do like that the HAI stats will work with almost any kind of backend system (or multiple backend systems in your case) and still all be integrated into a single, independent controller (the Omni system). This works because the HVAC control is independent of the communication.

Regarding the style, to each their own. :-) I think the RCS stats look nice as well. I have no connection to HAI except as a satisfied customer.

Kurt

Reply to
Kurt Delaney

Then you probably already know that your basic problem is the GC. For a project like that, everything should be spelled out in detail in the prints. If that were my house, I'd be concerned about more things than just zoning. I'd be taking pictures and making notes of everything done. I hope you have time to visit the job site every evening to check on things.

Reply to
Bob

If the HVAC contractors (yes, plural) are not 'up with the world' on the availability of the better controls, just think what kind of system you're getting.

There are a lot of opinions, but Tekmar is one of the best out there. There are several manufacturers that buy the Tekmar stuff and relabel it with their names.

Reply to
HeatMan

I've had a chance to contact most the tech support staffs for the vendors above. Tekmar is targeting the hydronic heating market whereas the other vendors are stronger on 3rd party integration and Internet control. Here are the main differences between Tekmar and the others.

Pro: Supports fast on-off cycles to modulate the temperature for radiant heating (PWM). This only works with slow moving systems like radiant heating. I really like this approach because the radiant heating system effectively becomes a variable temperature heating system, and should be able to maintain tight control of temperature.

Pro: Their higher end network thermostats are more like mini-controllers and can coordinate with other network thermostats without using a separate controller. For example, I can use the others thermostats as sensors to temperature average during AC.

Con: The 3rd party integration and Internet control is immature compared to other home automation thermostats. For example, Internet control is not available but when the gateway becomes available, it will require a Macintosh (wth?).

The bottom line is I'd rather make the most of the radiant heating system/forced air combo and hope for better integration a few years from now. Thanks all for your comments and insights and for HeatMan's link to Tekmar.

Reply to
chi

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.