Although thermostat could Be stuck in the open position, it can also be as simple as not enough water or a leak. Check if the gauge is hot and the air is cold. This indicates lack of water, or a bad or loose water pump belt. Also could be your actuator door is defective.
Replace Thermostat
What do you mean by "has no heat"? No air blowing out, blowing out cold air when heater is on, blowing nothing at all? Heater not turning on? What specifically is happening?
looking for answer
the heater matrix is blocked
Is it blowing cold air only or not blowing any air at all.
Probably a bad thermostat.
Your heat pump may not be blowing cold air because it could be low on refrigerant, have a faulty compressor, or a problem with the thermostat. It is recommended to contact a professional HVAC technician to diagnose and fix the issue.
Your central heat may be blowing cold air due to issues with the thermostat, a malfunctioning heating element, or a problem with the ductwork. It is recommended to check these components and consult a professional if needed to diagnose and fix the issue.
Your heat may be blowing cold air due to issues with the thermostat, low coolant levels, a malfunctioning heater core, or a problem with the blend door. It is best to have a professional inspect and diagnose the issue for an accurate solution.
There could be several reasons why your apartment's heat is blowing cold air. It could be due to a malfunctioning thermostat, a problem with the heating system, or air duct issues. It is best to contact your landlord or a professional HVAC technician to diagnose and fix the problem.
Car not blowing air or heat
The heat may be blowing cold air instead of warm air due to issues with the thermostat, a lack of enough coolant in the system, a malfunctioning heater core, or a problem with the blend door. It is recommended to have a professional inspect and diagnose the issue for proper repair.