Re: Wood Stove and HVAC Return Duct Proximity
When we were in the HVAC/R business it was a common thing to use the central heating ducting and fan to circulate heat from a wood or pellet stove. I've never installed a RA directly over a wood stove so can't comment on any codes in that regard. Some, not all, insurance companies require a temperature limit switch be installed in the RA duct close to the grill to detect high temperatures. I've never seen a code that required this option. This switch is designed to shut down the fan if temperatures exceed what the duct is designed to safely handle. This will keep the duct system from blowing fire thru the house in case of a fire. Well worth the investment in my opinion.
It's also possible, and I believe desirable, to install a low temperature sensor that will shut the fan off if the stove goes out and the air temperature drops. Why paddle cold air around?
These switching systems are not hard to install and should be wired to allow the central heating system to operate normally.
As with any wood, or other heating system, it's important to have up to date and properly operating smoke detectors.
I'd suggest you contact your local code officer and insurance for a definitive answer on this, it's a good question.
A gun and a parachute are much the same. When you need one nothing else will really suffice.