HVAC Frustration. Need Advice

[ano]

I'm not fully sold on the air exchanger either, but I have read in homes with high radon, the air exchanger can be tuned to keep a slightly positive air pressure in the house, which greatly reduces radon.  We had radon maybe 1.5 times the limit, so we added a vacuum system under our slab, which has dropped it to maybe 60% of the limit.  Still dripping it a bit more would be a plus. 
 
Even still, I plan to turn it off on the hottest days because I think they can be a big waste of energy.  On the cooler days, yes I certainly can open windows, but I have automation to automate those types of things.  I thought about a system with two dampers to bring in and exhaust air, but I'm not sure I want to be that unconventional.  For $1400 I think it is worth it to try. 
 
There are always the "is it neccessary questions"  just like the radon system.  Odds are if I didn't install it, we'd be fine, but then someone in the family gets lung cancer and you think a bit differently. 

 

[ano]

So, today my HVAC automation odyssey continues.  Today they are installing the wired thermostats (OmniStat2) and the zone controller.  I am very sure they have never installed a Honeywell zone controller before so I need to learn about it to make sure its done correctly.  
 
I decided not to go with the air-exchanger. Instead they are installing a damper which I can have the Omni open and close based on the outside temp.  This damper will allow outside air to be sucked into the air handler.  They said I only need this, but I believe I need a second damper to allow inside air to exit.  I can add that myself afterwards. 
 
When its between 60 to 78 out, the damper will open and let outside air in. It has an air filter to keep out the dust.  Outside that temp. range the damper closes.  It is a cheap solution that should do the trick.

 

[apostolakisl]

I think you made the most cost effective decision not getting those air exchangers.
 
The honeywelll is not hard to setup.  You wire directly from the thermostat to the honeywell board just as though the honeywell board were the hvac unit itself.  Then you run a wire from the honeywell board to the hvac unit exactly the same as if the honeywell board were a regular thermostat.  The last thing is to run the wires to the dampers.
 
Really the only complicated thing is figuring out exactly which one of the honeywell settings matches your system (heat pump, stages and so forth).
 
As far as the air escaping your house, I doubt your house is so sealed up that you need to provide a dedicated way for the air to get out when the intake damper opens.  I suppose you can figure that out once it is working by observing the air flow.

 

[ano]

I read the Honeywell zone controller instructions and I'm pretty impressed.  There are three ways that it can determine Stage 1 vs. Stage 2. 
1) with a timer, over a set time is Stage 2
2) % of zones, one zone calling is Stage 1, 2 - 3 zones, Stage 2
3) Thermostats, any OmniStat2 calls for Stage 2, then it runs Stage 2.
 
I think #3 is best for me, and I'm going to try that first. The OmniStats have lots of good logic to decide stage 1 or 2.
 
I know I'm making a lot of this AC Stage stuff, but note that I live in Phoenix where AC is on 8 months a year, and I'm an electric rate where I pay $11 a month extra for each KW of peak load from M-F, 12pm - 7pm during the month.  Just increasing the peak ONCE a month during those times for an hour will add lots to my bill.  So I DON'T want Stage 2 AC a minute more than I have to have it.  And I have 2 AC units.  So automation could potentially save me LOTS of money.

 

[apostolakisl]

Wow, never seen peak demand go against a residential bill.
 
But with all the home automation you have, you should be able to manage this pretty well.  Stuff like your ovens, laundry, water heaters, dish washers, and so forth could all be brought into the equation to balance your load over time.  Perhaps you can monitor the actual amp draw and set alerts as well.  Sounds like they give you a little buffer to shut stuff down by your "for an hour" comment so alerts may help you when automation falls short.
 
Perhaps you could figure a way to get more thermal mass in your house to help buffer things as well, letting you cool the house down at off hours and hold that during peak hours.