First Post - Room Not Heating to Set Thermostat Degree

[Sepehr84]

Hello everyone.
We have a 1-bedroom unit with baseboard heating, gas furnace for heating and boiler for hot water. Recently, the unit is not warming up enough to the degree set on the thermostat. I have changed the thermostat and the furnace seems to be working. For example the thermostat is set on 71, but the temperature never goes higher than 65.
I know the system has the capacity to get up to the temperature I have set; so something should be wrong. I just don’t know what.
Any advice would be greatly appreciated.

 

[Gasmk1]

What is the outside temp,

 

[RayW]

Have the adjacent units got the same system? Ask them what temperature they can achieve. When was the furnace last serviced? they don't run forever without attention.

 

[snowhead]

Does the furnace have filters , if so are they clean?
Has it worked in the past with the same oudoor temperature as now?

 

[Sepehr84]

Does the furnace have filters , if so are they clean?
Has it worked in the past with the same oudoor temperature as now?

Thanks for all the responses. The temperature outside is around 36-46 in NYC. The system was serviced about a month ago and had been working find as far as the tenant says. This a multi-family house and the other unit is a two-story unit, it has the same issue more or less but I had assumed it was because it is a single zone system and the heat goes upstairs mostly.
I have not checked the filters though; might they be the reason?