Our earlier embedded QoS-aware residential gateway (EmQRG) for real-time class-based queuing (CBQ) bandwidth management is reviewed and experimentally demonstrated. EmQRG's high QoS is demonstrated in conjunction with a wireless ZigBee network of temperature/humidity monitoring sensors. Critically, the EmQRG sends a top-priority over-temperature alarm when any temperature/humidity module reports a temperature exceeding a preset value. This emergency signal has top EmQRG transmission priority. Experiments verify the over-temperature alarm sends/receives “immediately” regardless of heavy network congestion or bottlenecking. The presented system easily expands to extensive networks containing many parallel systems or embedded sub-systems. The presented system is cost-effective implementable with available hardware and software.