furnace putting out too much heat

[catsonmars700]

Hello!

I live in a house with a small apartment attached to it, and we use one oil furnace to heat both living areas. The problem is that whenever we try to heat the house the furnace pumps enormous amounts of hot air into the apartment area, even if the thermostat in the apartment is turned off. We had the thermostat in the house set to 70 degrees this morning, and it was almost 100 degrees over in the apartment. One person I asked said it’s possible the furnace is just venting some excess heat, but I lived in that apartment for 2 years and used the furnace regularly, and we never had that much heat being dumped anywhere in the house.

Anyone out there have some idea of what’s happening here?

[Hube]

Furnaces don't "just vent some extra heat". We need some more info. Is this ducted layout a "split zoned system? Do you actually have 2 thermostats? or is this a NORMAL (no dampered zones) with 1 thermostat.? We will need answers to these questions befor we can give you any proper advice. Hube

[catsonmars700]

Yeah, I thought the idea that it was venting heat didn’t make any sense. We do have two thermostats – one in the house and one in the apartment. There is a heating duct and a set of controls for each building. The furnace can heat both areas independently (or at least it’s supposed to). Everything seems to work fine when the furnace is used only to heat the apartment; the trouble starts when we turn on the thermostat in the house.

[Hube]

This is a split type ,independent ZONE system. (or at least it should be) One could not offer much assistance to the problem without seeing it. Your best to get a Tech to come in and check it out, as the zone damper is not calibrated to each thermostat call. Good luck, Hube