Qingdao Haiang HVAC Equipment Co., Ltd.,

Qingdao Hiounce HVAC Equipment Co., Ltd., established in 1958, specializes in the R&D and manufacturing of gas-fired combination boilers, condensing boilers, and modular boilers—with an annual output of 120,000 units. In partnership with Italy’s Cosmo Group, the company is committed to delivering international-standard, high-quality, low-carbon, and environmentally friendly gas thermal energy equipment solutions.

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Safe Guard

Safety Protection

Air Filter Protection

Effectively filters airborne impurities entering the unit, keeping the combustion system clean to ensure complete combustion, efficient operation, and extended service life of core components.

Water System Protector

Provides effective protection for internal water system components, reducing the impact of scale buildup, corrosion, and particulate deposits—enhancing overall system operational stability.

Gas Filtration Protection

Filters particulate contaminants from the gas supply, lowering the risk of valve or combustion system blockage and ensuring safe, stable operation of the gas-fired condensing boiler.

Primary Freeze Protection

When the heating water temperature drops to ≤8°C, the circulation pump automatically runs continuously until the water temperature rises to ≥10°C, effectively minimizing the risk of freezing in low-temperature environments. This function remains active even when the unit is powered off and displays either the heating water temperature or a corresponding fault code.

Secondary Freeze Protection

When the heating water temperature drops to ≤5°C, the system automatically starts the circulation pump and ignites to heat the water; combustion stops once the water temperature reaches ≥30°C, followed by a post-circulation phase—further enhancing freeze resistance in cold conditions.

Tertiary Freeze Protection

When the heating water temperature drops to ≤3°C, the system stops the circulation pump and enters a freeze-protection fault state, displaying a dedicated freeze fault code to alert users to address low-temperature risks promptly.

Heating System Pressure Stabilization Protection

Equipped with an expansion tank that absorbs pressure fluctuations caused by thermal expansion of the heating water, maintaining stable system pressure and improving overall heating system safety.

Dry-Fire Bypass Protection

When return water flow is restricted, the automatic bypass valve opens to ensure sufficient water flow through the primary heat exchanger—preventing dry-firing or overheating damage due to insufficient flow.

Overcurrent Protection

Triggers protective action immediately upon detecting abnormal overcurrent, reducing electrical circuit, equipment, and personnel safety risks—and ensuring stable, reliable unit operation.

Heating Water Temperature Limit Protection

When heating water temperature reaches 80°C, the system automatically activates temperature-limit protection and shuts off high-fire combustion. The unit will only restart after the return water temperature falls at least 25°C below the setpoint—avoiding safety hazards associated with prolonged high-temperature operation.

Low Water Pressure Protection

The unit restricts startup when system water pressure is too low. Normal heating system operation is only permitted when pressure exceeds 0.3 bar—preventing equipment damage caused by low-pressure or no-water conditions.

Three-Way Valve Anti-Jamming Protection

Ensures smooth, reliable actuation of the three-way valve via anti-sticking mechanisms—guaranteeing seamless switching between space heating and domestic hot water modes.

Water Circuit Filtration Protection

Effectively traps sand, rust, and other particulates in the water circuit, maintaining unobstructed water flow and protecting critical components—including the heat exchanger and circulation pump—from damage.

Primary Heat Exchanger Overheat Protection

Monitors and prevents excessive temperatures in the primary heat exchanger, enhancing heat exchange system safety and supporting long-term, stable equipment operation.

Pre-Purge Protection

Automatically clears residual gas from the combustion chamber before ignition—reducing the risk of explosive ignition and ensuring safe, reliable, and stable combustion.

Circulation Pump Auto-Start Protection

Enables automatic pump activation based on operational demand—preventing pump seizure due to prolonged inactivity while also mitigating localized overheating risks and ensuring overall system reliability.

Electric Leakage Protection

Continuously monitors for electric leakage and rapidly cuts power in case of anomalies—eliminating electrocution hazards and improving overall electrical safety.

Power Failure Protection

Automatically halts core operations and shuts off the gas supply during power outages. Upon power restoration, the unit restarts following a secure logic sequence—ensuring both equipment and user safety.

Overtemperature Protection

Prevents system water or critical component temperatures from exceeding safe limits—avoiding equipment damage or potential safety incidents caused by excessive heat.

System Low Water Pressure Protection

Automatically restricts operation when system water pressure is insufficient—preventing poor water circulation, abnormal heat transfer, or dry-firing risks and ensuring safe, stable heating system performance.

Gas Leak Protection

Immediately cuts off the gas supply and halts operation upon detecting abnormal faults or gas-related risks—preventing gas accumulation that could lead to poisoning, explosion, or fire.

Gas Pressure Stabilization Protection

Maintains consistent gas supply pressure to ensure complete, stable combustion—improving thermal efficiency and reducing the likelihood of combustion anomalies.

Manual Reset After Gas Interruption Protection

When flame detection fails due to gas interruption, the system automatically attempts re-ignition. After multiple consecutive failed attempts, it enters a fault state requiring manual reset—preventing unsafe repeated startups.

Flue Blockage & Backdraft Protection

Ensures smooth exhaust of flue gases and prevents hazards caused by flue obstruction or external backdraft—maintaining safe, stable combustion and reliable equipment operation.

Air Pressure Protection

Automatically extinguishes the flame and displays a fault code if flue blockage or reverse draft occurs—preventing safety hazards caused by abnormal exhaust conditions.

Post-Purge Protection

After combustion stops, the fan continues to purge residual gases from the combustion chamber and reduces localized overheating—extending the service life of internal combustion chamber components.

Circulation Pump Anti-Seizing Protection

If the circulation pump remains inactive for 24 hours, the system automatically forces it to run for 60 seconds—preventing pump seizure due to long-term idleness and ensuring dependable water circulation system performance.

Critical Temperature Protection

Activates protective measures automatically when system or core component temperatures approach hazardous thresholds—preventing component failure and major safety incidents.

Power-Outage Memory Function

Automatically saves all operational settings during a power outage. Upon power restoration and restart, the unit resumes operation using pre-outage settings—enhancing user convenience.

Full-Unit Electronic Control Self-Diagnostic Protection

Performs automatic diagnostics on key components during startup and operation—identifying potential anomalies early to ensure safe startup and stable operation.

Full-Unit Electronic Control Operational Protection

Continuously monitors the status of electrical circuits, combustion, water systems, and other subsystems—promptly responding to anomalies by isolating risk sources and safeguarding both equipment and user safety.

IPX4-Rated Enclosure Waterproof Protection

The enclosure meets IPX4 splash-resistance standards, protecting internal electronics and core components from everyday water splashes—reducing short-circuit and failure risks.

Gas Valve Fault Protection

Monitors gas valve operation in real time and initiates protective action immediately upon detecting valve abnormalities—preventing combustion risks caused by gas control failure.

Flue Gas Sensor Fault Protection

Monitors flue gas temperature via the flue gas sensor and feeds data back to the electronic control system—enabling combustion modulation, overtemperature protection, and early fault warnings.

Fan Speed Monitoring Protection

Continuously verifies that fan speed remains within safe operating ranges—ensuring adequate combustion air supply and smooth flue gas discharge, and preventing equipment damage or safety hazards caused by fan malfunction.

Fan Operation Monitoring Protection

Monitors fan startup, shutdown, and running status throughout operation—ensuring proper combustion air supply and flue gas exhaust, and blocking operational risks under abnormal conditions.

Condensate Drainage Blockage Protection

Prevents equipment water accumulation, corrosion, or operational anomalies caused by blocked condensate drainage—ensuring safe, unobstructed condensate removal.

Heating Water Temperature Sensor Protection

Monitors heating water temperature and operational status in real time—ensuring stable water temperature output and triggering protective actions promptly under abnormal conditions to prevent equipment damage.

Differential Pressure Protection

Detects water circuit differential pressure to assess flow continuity—preventing dry-firing or overheating damage to the heat exchanger caused by pipe blockages, pump failures, or low water levels.

Domestic Hot Water Temperature Limit Protection

Maintains domestic hot water temperature within a safe range—preventing scalding injuries while also protecting heat exchangers and related water system components.

Safe Grounding Protection

Reliably channels leakage current to ground—reducing electrocution risk and shielding the electronic control system from lightning surges, static electricity, and other interference.

Residual Flame Protection

Prevents lingering flames after combustion stops—reducing risks of gas leakage and fire, and ensuring safe equipment shutdown.

Ignition Safety Protection

Monitors the entire ignition process to ensure safe, reliable ignition. If ignition fails or flame behavior is abnormal, the system immediately enters protective mode.

Flue Gas Temperature Overlimit Protection

Restricts flue gas temperature within safe limits—preventing equipment damage or safety hazards caused by abnormal combustion, flue issues, or excessively high exhaust temperatures.

Three-Minute Delay Protection

After the wall-mounted boiler shuts down, the system enforces a three-minute delay before restarting—preventing frequent cycling and ensuring safe, stable combustion system operation.

Voltage Protection

Protects the electronic control system against damage caused by overvoltage, undervoltage, or abnormal voltage fluctuations—ensuring safe operation under stable power supply conditions.

Air Venting Protection

Automatically expels trapped air from the water system—preventing air locks that impair water circulation and heat transfer efficiency, while also protecting the pump and water system components.

Communication Fault Protection

Monitors communication integrity among the main control board, sensors, actuators, and other components—preventing loss of control or functional failure due to communication errors.

Balanced Combustion Protection

Draws combustion air from outdoors and forcibly expels exhaust gases outside—preventing indoor oxygen depletion and exhaust gas leakage, thereby enhancing safety and usability.

Unexpected Flame-Out Protection

Immediately cuts off the gas supply and displays a fault notification if unexpected flame extinction occurs during operation—preventing gas leaks that could cause poisoning, explosion, or fire.

Domestic Hot Water Filtration Protection

Effectively traps impurities from municipal water supplies—keeping domestic hot water piping and heat exchangers clear, reducing clogging risks, and improving hot water delivery reliability.

Air Lock Protection

Automatically vents residual air from the system—preventing air locks that disrupt water circulation and pump seizure, ensuring smooth, uninterrupted heating system operation.

Water Hammer Protection

Leverages a sealed expansion tank to absorb sudden pressure spikes in the water system—minimizing mechanical stress and damage to pipes and equipment components caused by water hammer effects.

Electrical Circuit Anti-Interference Protection

Enhances the electronic control system’s immunity to pulse high-voltage transients and other electromagnetic disturbances—preventing controller lockups or erroneous actions.

Digital Fault Diagnostic Protection

Continuously monitors the status of electrical circuits and critical components—automatically displaying fault codes when anomalies occur for rapid identification and maintenance.

NTC Sensor Fault Detection Protection

Shuts down the unit and triggers an alarm if the temperature sensor experiences short-circuit or open-circuit faults—preventing operational risks caused by inaccurate temperature readings.

Negative-Pressure Combustion Protection

Improves combustion completeness via negative-pressure combustion design—reducing carbon monoxide generation and further enhancing combustion safety and environmental performance.

Cybersecurity Protection

Implements security safeguards across identity authentication, data transmission, and device operation—preventing unauthorized access, data breaches, and unsafe remote manipulation.

Remote Notification Protection

When connected to a remote control system, abnormal operation or fault alerts are instantly pushed to the user’s smartphone—enabling timely awareness and response to equipment status changes.

Control Terminal Security Hardening

The mobile app employs code obfuscation, automatic logout after idle timeout, and other security mechanisms—reducing the risk of remote control privilege compromise and enhancing smart-control safety.