The answer to 'dehumidifier not heating' is that the most common causes are a faulty heating element, thermostat issues, or a problem with the control board. Symptoms may include the unit not getting warm, poor dehumidification performance, or the compressor running but no heat being produced.
Troubleshooting steps include checking the heating element for continuity, testing the thermostat, and inspecting the control board for any damaged components. If you are comfortable working with electrical systems, you may be able to replace a faulty heating element yourself. However, if you're not confident in your DIY skills or the problem is more complex, it's best to call in a professional HVAC technician to diagnose and repair the issue.