I have an older apartment which is not equipped with conventional air duct. This makes it easily difficult to heat in the winter. In the kitchen, we’ve installed a compact, natural gas heater. This heating system is a ventless, single-stage heater. Because it is ventless, it creates an oily film on the windows in the kitchen. I have a pair of antique French doors which each have twelve small windows. These windows are time-consuming plus aggravating to clean. In the summer, I rarely need to worry about them. During the winter, they are forever cloudy plus in need of a thorough scrubbing. Because the heating system is a single-stage unit, it blasts heat at maximum capacity component it achieves the thermostat setting. It then shuts down plus cools itself by blowing cool air. The constant on plus off cycling results in unpleasant temperature swings. The ventless heating system is also easily temperamental plus requires constant filter cleaning. At least once per week, I need to remove the 2 filters plus meticulously clean them. If there is any debris clogging the filters, the warning light on the component starts blinking red, and when this happens, the heating system will no longer shutdown. It keeps running on maximum capacity, plus I worry that it might overheat. Overheating could disfigure the heating system or even present a safety hazard. Once a year, the filter cleaning is not acceptable, plus I need to take the heating system apart plus clean it with high pressure air. The pressurized air removes any buildup of dust. Unfortunately, this dust then fills my kitchen. I should perform this task in the summer, as a proactive strategy, when I can open the windows. Instead, I typically wait until the heating system refuses to operate properly, in the middle of the winter.