HS-BLH-EPC13-XH5-P1.0 Water Heater PCBA

HS-BLH-EPC13-XH5-P1.0 Instant Electric Water Heater PCBA with Real-Time Flow Display

The HS-BLH-EPC13-XH5-P1.0 is a customizable instant electric water heater PCBA developed for appliances requiring wide-voltage operation, touch control, preset temperature selection and real-time water-flow information.

The complete solution combines the HS-BLH-EPC13-XH5-P1.0 power board with the HS-BLH-3526-4KEY-XH4-C1.0 display board. Based on a BYD control IC in a 28-SOP package, it integrates water-flow activation, temperature adjustment, automatic temperature-control learning, power-level configuration, intelligent display functions and multiple safety diagnostics.

SunSam can customize the hardware, firmware, key layout, display artwork, sensor inputs and control logic according to the customer’s appliance structure and target-market requirements.

Key Specifications

Power Board Model: HS-BLH-EPC13-XH5-P1.0

Display Board Model: HS-BLH-3526-4KEY-XH4-C1.0

Control IC: BYD Control IC in 28-SOP Package

Standard Power Supply: Switch-Mode Power Supply

Standard Input Voltage: 85–280 VAC

Optional Transformer Input: 180–265 VAC

Operating Frequency: 50/60 Hz

Control Interface: Four-Key Touch Control

Preset Temperatures: 38°C, 42°C and 45°C

Default Start-Up Temperature: 38°C

Temperature Setting Range: 30–55°C

Power-Level Settings: P3, P4, P5, P6, P7 and P8

Reference Power Mapping: P7 = 7000 W; P8 = 8800 W

Touch Panel Compatibility: 4 mm Glass Panel or 2 mm Plastic Panel

Temperature Sensor: 50K NTC

Flow Activation Threshold: 1.4 L/min

Heating Shutoff Threshold: 1.2 L/min

Leakage Detection Range: 15–25 mA

Buzzer Frequency: 2.5 kHz

Controller Operating Temperature: -15°C to 85°C

Operating Humidity: 10–95% RH

Wide-Voltage and Dual-Frequency Operation

The standard configuration uses an 85–280 VAC switch-mode power supply. During internal sample validation, the controller operated continuously at 280 VAC for eight hours without abnormality.

An optional transformer configuration supports 180–265 VAC input and completed an eight-hour continuous operation test at 265 VAC.

The controller also operated normally at both 50 Hz and 60 Hz, allowing the platform to be adapted for different regional electrical systems.

Four-Key Touch Interface

The interface provides four touch keys:

- Preset Temperature

- Temperature Down

- Power

- Temperature Up

The Preset Temperature key cycles through 38°C, 42°C and 45°C. The controller initializes at 38°C when it is switched on.

The Temperature Up and Temperature Down keys support continuous adjustment when pressed for more than one second. Every valid key operation produces one audible beep.

The touch keys can operate through a 4 mm glass panel or a 2 mm plastic panel. The panel artwork, icons, language and key arrangement can be customized to match the customer’s enclosure and brand design.

Configurable P3–P8 Power Levels

The firmware supports P3, P4, P5, P6, P7 and P8 power-level settings.

The sample report records the following reference mappings:

- P7 corresponds to 7000 W

- P8 corresponds to 8800 W

The wattage values for P3–P6 are not defined in the report and should be configured according to the final heating system.

The actual rated power depends on the heating element, power-control components, wiring, terminals, PCB copper design and thermal-management system. The firmware code alone does not determine the PCBA’s electrical load capacity.

After a power-level setting is selected, the controller automatically exits and saves the setting after five seconds without key operation.

Real-Time Water-Flow and Temperature Display

When power is connected, all display segments illuminate for approximately one second and the buzzer sounds once. This provides a basic visual and audible self-check.

During operation, the display can show:

- Configured power level

- Set water temperature

- Actual outlet water temperature

- Real-time water-flow information

- Water-flow status

- Heating status

- Fault codes

After a temperature key is pressed, the screen displays the set temperature for approximately three seconds before returning to the actual outlet water temperature.

When excessive water flow is detected, the display shows “LL”. Decimal-point indicators are used to distinguish water-flow and no-flow conditions.

Automatic Sleep and Wake-Up

If the controller is in standby with no water flow and no key operation, the display automatically turns off after approximately 30 seconds.

The display wakes automatically when water flow is detected or any key is pressed. This function provides a cleaner interface while reducing unnecessary display operation.

The sample also completed a smartphone recording test. The display remained clear without visible flicker, helping improve product photography, video recording and online demonstrations.

Water-Flow Activation

The reference heating activation threshold is 1.4 L/min. Heating stops when the flow drops to approximately 1.2 L/min.

The controller coordinates the detected water-flow condition with the heating output to prevent normal heating operation when the water supply is insufficient.

The sensor interface and flow thresholds can be customized after engineering evaluation according to the appliance water path, heating power and required operating logic.

Automatic Temperature Learning

The controller supports inlet and outlet water-temperature monitoring through 50K NTC temperature sensors.

The firmware includes automatic temperature-control learning, calibration and parameter memory. This allows the controller to adapt its control parameters according to water flow, inlet temperature, outlet temperature, heating power and the thermal characteristics of the complete appliance.

Sample Temperature-Control Performance

Temperature-control testing was performed with an inlet water temperature of 25°C and flow rates of 1.5 L/min and 3.0 L/min.

After the initial learning calibration, the controller achieved temperature stabilization within 20 seconds under the recorded conditions.

At a flow rate of 1.5 L/min:

- 36°C setting: measured at 35–37°C within 15–20 seconds

- 40°C setting: measured at 40–42°C within 10–15 seconds

- 45°C setting: measured at 44–46°C within 8–12 seconds

- 48°C setting: measured at 48–50°C within 6–8 seconds

At a flow rate of 3.0 L/min:

- 36°C setting: measured at 36–37°C within 15–20 seconds

- 40°C setting: measured at 39–42°C within 8–12 seconds

- 45°C setting: measured at 44–46°C within 8–10 seconds

- 48°C setting: measured at 47–49°C within 6–8 seconds

Actual temperature accuracy and stabilization time depend on the inlet temperature, flow rate, heating power, sensor position and complete water-path design.

Safety Protection and Fault Diagnostics

E1 Over-Temperature Protection

When the detected water temperature reaches 60°C or above, the controller stops heating. Heating automatically resumes after the temperature falls to 50°C.

E2 Leakage-Current Protection

If a leakage-current fault is detected, the controller disables heating and activates an alarm. Normal operation can resume after the fault is repaired and the appliance is restarted.

The sample report specifies a leakage-detection range of 15–25 mA, with a recorded sample value of 24 mA. The final threshold must be validated with the selected leakage-detection component and complete-appliance safety design.

E4 Outlet Temperature Sensor Fault

If the outlet temperature sensor is open or short-circuited, the controller disables heating. It automatically recovers after the fault is corrected.

E3 Inlet Temperature Sensor Fault

If the inlet temperature sensor is open or short-circuited, the controller disables heating. It automatically recovers after the fault is corrected.

E0 Zero-Crossing Fault

The firmware supports zero-crossing detection and burst-fire heating control. Normal operation resumes after the fault is corrected and the appliance is restarted.

E9 Communication Diagnostics

The firmware reserves E9 for communication-fault diagnostics. The alarm behavior, heating response and recovery method can be defined according to the final customer program.

Environmental and Reliability Validation

The controller operating-temperature specification is -15°C to 85°C, with an operating-humidity range of 10–95% RH.

The sample completed the following internal validation:

- Eight hours of operation at 280 VAC

- Eight hours of operation at 265 VAC with the transformer configuration

- Functional operation across 85–250 VAC

- Operation at both 50 Hz and 60 Hz

- Eight hours of operation at 85°C and 85% RH

- Whole-unit dielectric withstand testing at 1800 V and 5 mA for one minute

- Thirty fluorescent-lamp switching cycles at intervals of 0.5–3 seconds

- Smartphone display recording without visible flicker

No abnormal operation was recorded during these tests.

The report notes that heating power was limited to approximately 2 kW below 0°C. Therefore, the -15°C lower operating limit should not be interpreted as full-power heating performance.

These results represent internal sample validation and should not be interpreted as independent EMC, electrical-safety or complete-appliance certification.

Typical Applications

This instant electric water heater PCBA can be used in:

- Residential instant electric water heaters

- Commercial point-of-use water heaters

- Kitchen and washbasin hot-water appliances

- Hotel and apartment water-heating equipment

- Touch-control water heaters with glass or plastic panels

- Appliances requiring real-time flow display

- Water heaters with automatic sleep and wake-up functions

- Products requiring selectable temperature presets

- Custom temperature-controlled heating appliances

OEM/ODM Development and Manufacturing

Foshan Shunde SunSam Electronic Co., Ltd. has 15 years of experience in custom PCBA development and manufacturing. Water heater control boards are one of our core product categories.

Our one-stop OEM and ODM services include:

- Product-function evaluation

- Hardware and firmware development

- Circuit and PCB design support

- Component sourcing

- Prototype production

- SMT assembly

- Wave soldering

- Firmware programming

- ICT and FCT testing

- Functional verification

- Material and production traceability

- Volume manufacturing

The input voltage, temperature presets, power levels, key layout, display content, sleep timing, flow thresholds, sensor parameters, protection functions and fault codes can be customized after engineering evaluation.

Start Your Custom Water Heater PCBA Project

Customers can provide an existing sample, BOM, Gerber files, schematic, enclosure drawing or functional specification for evaluation.

For an accurate technical proposal and quotation, please provide:

- Target-market voltage and frequency

- Heating-element rated voltage and power

- Power-control method

- Required temperature range

- Water-flow sensor specifications

- Temperature-sensor specifications

- Display and key-layout requirements

- Enclosure dimensions

- Required testing standards

- Estimated order quantity

- Project schedule