Heating, Air Conditioning, Fridge, HVAC/boiler not heating apartment


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?


You would have to see if the OD sensor is adjustable via thermostat instructions, or boiler control where ever the OD probe hooks to or possible your OD sensor is off calibration, or a signal is not reaching the boiler control to adjust boiler temperature. there are ways to check calibration . You would need to see if your sensor can be calibrated. You probably have something like a temperature offset OD probe, the colder the outdoor temperature the higher the boiler temperature it's suppose to maintain.

Have you ever noticed your boiler temperature vary in the past years or was it always a set temperature?

Does your zone valves ( if that's what you have ) opening completely , circulator pump pumping correctly?

Can't you bypass the OD sensor for test purposes via a troubleshooting guide for your system?

Do you know the sequence of operation of your system? Didn't the installing Contractor leave info with the boiler? In regards to how it's suppose to work under different OD temperature.

Are you the original owner? If so if the system is not that old, or whoever services your system should know how everything suppose to work.

Heating, Air Conditioning, Fridge, HVAC

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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