What would be the reason that half of the heater works in a c240 Mercedes?

If half of the heater in a C240 Mercedes is not functioning, it could be due to a few potential issues. One common reason is a malfunctioning blend door actuator, which controls the flow of air between the hot and cold sides of the system. Another possibility is a clogged heater core, which would restrict hot coolant from circulating properly. Additionally, low coolant levels or issues with the climate control system could also contribute to uneven heating.