thermostat
I have a southern California two-story home built in the late '70s. It's a single-zone system with both heating and cooling. The thermostat is located downstairs. In the summer the upstairs gets too hot and in winter the downstairs is too cold.
I'd like to put a wireless second thermostat upstairs and pair it with the hard-wired one downstairs. That way the system can tell the actual max./min. of the house temperature.
Are there any thermostats out there to do this? Would it even work?
There are a few things you can do which can help:
1) Adjust the dampers in the duct work. Partially close dampers in the ducts going to the first floor and fully open the ones to the second. Take some time to mark them so you know what goes where. It will probably take a few tries to get them set right. That's usually the first thing an HVAC guy will do for this situation.
2) Seal off the leaks in your duct work. Go around and find leaks and seal them with the aluminum backed tape. It's real sticky and has a peal off backing. Oddly enough, duct tape always seems to come loose on my duct work. Go figure. There are services which will come out and blow a smokey substance through your system to locate leaks and seal them.
3) This can be controversial, but you could cover your low returns in the summer and high returns in the winter. The theory is that this will pull more warm air out in the summer and more cold air out in the winter. There are magnetic covers you can get for this purpose like this:
But you may have better luck with stronger magnetic sheets and custom cut them yourself.
I'm not a fan of closing registers, but that's probably one of the simplest things to do.
There are systems that can be installed which will automatically adjust dampers in your duct work based on thermostats placed throughout the house, but they're pricey.
I'm really happy with my Honeywell wireless thermostat. Battery lasts a very long time and it works through 4 floors. A quick Google search shows several options below $100... Something like this for $65 perhaps? Not the one I have though and not sure if it includes the receiver.
Best Answer
What you actually need is a single thermostat that has support for one or more secondary remote thermometers. I believe the Honeywell TB8220U1003 supports this via this part:
Remote Thermometer http://customer.honeywell.com/Honeywell/getliterature.axd?literatureID=C7189U_color_3in.jpg
As a side note, it is often necessary to properly balance your HVAC system depending on the season by adjusting the dampers to increase/reduce the airflow to certain areas based on the season. Also remember to open your cold air returns in the winter. You might not need a different thermostat at all!