I recently moved to upstate NY and am trying to figure out what kind of heating system(s?) I have. I'll walk you through what I know (or think I know) and please let me know if this is correct or if you have an advice.
"Outline.png" is a basic outline of my house.
First, I don't have central air - I have window units.
In my basement I have a hydronic gas boiler. This can be seen in "boiler.jpg" and "hydronic.jpg".
On my first floor I have two Honeywell thermostats, each one controls baseboard heaters as shown in "1st floor.jpg".
When I open these thermostats, it looks like what is shown in "Honeywell Thermostat innards.jpg" - there are two wires connected to the "R" and "W" terminals. I assume this means it is single stage heat, low voltage. I measured the voltage between the R and W terminals and I got 28.6VAC (not VDC?).
Now, up on my second floor I don't have any Honeywell thermostats - instead I have a bunch of these old Eaton Mears M401 thermostats, as shown in "Mears M401.jpg". There are three wires running into the M401 - ground, black, and red (I know color means very little). I didn't measure their voltages. I believe these are only used for line voltage electric baseboard heating? So this means all the zones my second floor are electric, not gas? Or could they have run the copper pipes from the basement up to the 2nd floor baseboard heaters to the boiler but left the old thermostats? That doesn't make sense but is it possible?
It looks to me like I have two different heating systems - gas on the first floor and electric on the second. Since gas is cheaper I take it this means I should rely on my 1st floor heating and let the air rise to heat my 2nd floor as much as possible.
One last question - if I want to upgrade the M401 thermostats on the second floor, I would need to buy line voltage thermstats for electrical baseboards, right?