said by PhoenixDown:Hi Folks 
## Background ## I have a 2 family house heated by a boiler type of furnace. The 1st and 2nd floors have steam heated radiators. The basement is heated with baseboard heating on a separate zone. I have one thermostat, an older Honeywell unit with wands and manual set blue/red pins to determine when the heating should come on.
Lets take a look at the OPs first post. He says the 1st and 2nd floors are on one zone. I am going to assume these "steam" radiators are cast iron. (more on that shortly). Then the OP said the basement is on its own zone with baseboards. OK so we have first and second floors on one zone. That includes the APT on the 2nd floor. One T-Stat controls those floors. I assume that T-Stat is on first floor. In the basement there is another zone on its own T-Stat. This zone is served by baseboards. This is all on one boiler having TWO zones. This does NOT sound like steam heat to me. I have a hunch this is hydronic / force hot water / circulating hot water heat. Older hydronic systems used cast iron radiators that looked like steam heat but were really forced hot water. Since this seems to be an older system i am leaning towards the basement zone being on a separate pump rather then a zone valve served system. Regardless the issue is the tenant is on the same zone as the first floor and any "management" the OP applies will affect the tenant as well. So lets say the OP goes to work and lowers the heat the tenant would be affected as well. The tenant's heat would need to be separated onto its own zone. This may and may not be viable depending on the plumbing . If the second floor can be easily split off another (third) zone could be added and tenant have their own T-Stat. A more costly option if plumbing was right is second floor could be put on their own boiler and they pay their own heat . Either of these would make managing the land lord zones doable in some form or another without affecting the tenant.
