Heating, Air Conditioning, Fridge, HVAC/boiler not warming room


I have a Laars Mascot FT combi heating system with baseboard radiators. The dhw setting is 120 F (and works well) The Heat setting is 150 F and on colder days the thermostat (Honeywell) room temp wont go above 70/71 F even if I crank it up to 79F. There is an outside sensor connected to the unit as well. At best the radiators just stay luke warm. Any suggestions as to how to fix this problem?

Most boilers will allow the heater to go to maximum heat if the OD sensor fails.  So if you simulate a failure by temporarily removing a wire from the terminal where the sensor is plugged in you may find the comfort and warmer radiators you desire.

The other thing that you can do is to see if the OD reset control can be adjusted so as to provide warmer water than you get now with the current settings.  The installation guide should give you instructions on how to make these changes using the boiler control interface.

The other thing is are you sure that your radiators are full of water (no air)?  Is the pump sufficient to provide adequate water flow.  

Heating, Air Conditioning, Fridge, HVAC

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Mike Reavis


Questions related to "Wet Heat". This is heating your home, office etc. with radiators, panels, and convector apparatus. Steam and water heat. I can answer questions about boilers, piping,and associated parts of these systems. Please do not ask for specific information about how I feel about one boiler, etc. over another--These questions should be directed to a licensed contractor that you know of, or that your neighbors and colleagues look to to provide solutions.


I have 20 plus years experience, which has lead to passing my state master HVAC license.


Completed college

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I work on the manufacturer's side of the business currently

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