Understanding Pump Telemetry

This guide explains the key metrics reported by the ALPHA HWR pump and how to interpret them for optimal system performance.

Core Metrics

Flow Rate

What it is: Flow rate measures the volume of water circulating through the pump per unit time.

Units:

m³/h (cubic meters per hour) - Primary unit used by the pump
GPM (gallons per minute) - Common in North America
Conversion: 1 m³/h ≈ 4.40 GPM

Typical Values for ALPHA HWR:

ALPHA HWR 15-29: 0.0 - 2.5 m³/h (0-11 GPM)
ALPHA HWR 15-55: 0.0 - 3.1 m³/h (0-13.6 GPM)

Why it's important:

System Coverage: Higher flow rates ensure hot water reaches all fixtures quickly. Insufficient flow results in lukewarm water at distant taps.
Tankless Heater Compatibility: Tankless water heaters require minimum flow rates to activate (typically 0.4-0.8 GPM). The pump must maintain this threshold.
Pipe Sizing Validation: Flow rates can reveal pipe sizing issues:
Very low flow (< 0.5 m³/h) may indicate undersized pipes or blockages
Very high flow (> 3.0 m³/h) may indicate oversized pipes or system leaks
Energy Efficiency: Flow directly correlates with pump power consumption. Higher flow = more energy. The AUTOADAPT mode optimizes flow based on actual temperature needs.
Flow-Accelerated Corrosion (FAC): Excessive flow rates can accelerate pipe corrosion, especially in copper systems. The ALPHA HWR includes configurable flow limits by pipe diameter:
1/2" pipes: 1.5 GPM limit (0.34 m³/h)
3/4" pipes: 2.3 GPM limit (0.52 m³/h)
1" pipes: 3.8 GPM limit (0.86 m³/h)

Reading Flow:

from alpha_hwr import AlphaHWRClient

async with AlphaHWRClient("YOUR-DEVICE-UUID") as client:
    telemetry = await client.get_telemetry()

    flow_m3h = telemetry.flow_m3h
    flow_gpm = flow_m3h * 4.40  # Convert to GPM

    print(f"Flow: {flow_m3h:.2f} m³/h ({flow_gpm:.2f} GPM)")

Head Pressure

What it is: Head pressure (also called differential head) measures the pressure difference the pump creates between its inlet and outlet. It represents the pump's ability to push water through the system against resistance.

Units:

m (meters of water column) - Primary unit
ft (feet of water column) - Common in North America
psi (pounds per square inch) - Absolute pressure
Conversions:
1 m H₂O ≈ 3.28 ft ≈ 1.42 psi ≈ 9806.65 Pa

Typical Values for ALPHA HWR:

ALPHA HWR 15-29: 0.0 - 2.9 m (0-9.5 ft, 0-4.1 psi)
ALPHA HWR 15-55: 0.0 - 5.5 m (0-18 ft, 0-7.8 psi)

Why it's important:

System Resistance Indication: Head pressure reveals how hard the pump is working against system resistance:
Low head (< 1.0 m): Short pipe runs, wide pipes, few elbows - easy system
Medium head (1.0-3.0 m): Typical residential hot water recirculation
High head (> 3.0 m): Long pipe runs, narrow pipes, many elbows/fittings, multiple floors
Blockage Detection: Sudden increase in head pressure can indicate:
Partially closed valves
Air locks in the system
Sediment buildup or scaling
Check valve malfunction
Pump Performance Verification: The pump's performance follows a curve where head decreases as flow increases. Abnormal head-flow relationships indicate problems.
Control Mode Selection:
Constant Pressure mode: Maintains steady head regardless of flow - ideal for multi-zone systems with thermostatic valves
Proportional Pressure mode: Adjusts head proportional to flow - energy-efficient for single-zone systems
Constant Curve/Speed mode: Follows fixed performance curve
Energy Optimization: Higher head requires more power. If the system can maintain adequate circulation at lower head, reducing the setpoint saves energy.

Reading Head:

from alpha_hwr import AlphaHWRClient

async with AlphaHWRClient("YOUR-DEVICE-UUID") as client:
    telemetry = await client.get_telemetry()

    head_m = telemetry.head_m
    head_ft = head_m * 3.28  # Convert to feet
    head_psi = head_m * 1.42  # Convert to psi

    print(f"Head: {head_m:.2f} m ({head_ft:.2f} ft, {head_psi:.2f} psi)")

Performance Relationships

Pump Curve

The relationship between flow and head follows the pump's performance curve:

At zero flow (shutoff head): Maximum head, pump closed or blocked
At maximum flow: Minimum head, fully open system
Operating point: Where system resistance curve intersects pump curve

Example Operating Points:

Scenario	Flow (m³/h)	Head (m)	Power (W)	Interpretation
Ideal	1.2	2.5	25	Balanced system, good circulation
Restricted	0.5	4.0	30	High resistance, check for blockage
Oversized	2.5	1.0	35	Low resistance, may waste energy
Shutoff	0.0	5.5	15	Closed valve or air lock

Power Consumption

Power consumption relates to both flow and head:

Power ∝ Flow × Head

Typical Power Draw:

ALPHA HWR 15-29: 2-21 W
ALPHA HWR 15-55: 2-38 W

Energy-Saving Strategies:

Use AUTOADAPT mode to automatically optimize flow/head based on temperature
Enable scheduling to run pump only when hot water is needed
Configure flow limits appropriate for your pipe diameter
Set minimum head just sufficient for system (don't over-pressurize)

Temperature Metrics

Media Temperature

What it is: Estimated temperature of the water flowing through the pump.

How it works: The ALPHA HWR doesn't have a direct water temperature sensor. Instead, it estimates media temperature based on thermal sensors on the pump housing and internal algorithms.

Typical Values:

Cold water: 10-20°C (50-68°F)
Hot water recirculation: 35-60°C (95-140°F)
Warning threshold: > 60°C (140°F) may trigger protection

Why it's important:

System Performance Verification: Confirms hot water is actually circulating
Temperature Control Modes: Used by AUTOADAPT and Temperature Control modes to regulate pump operation
Thermal Protection: Pump automatically reduces speed if water is too hot
Comfort Monitoring: Ensures hot water availability meets user expectations

Accuracy Limitations:

±5°C typical accuracy
Best accuracy when pump has been running continuously
Less accurate immediately after startup or during rapid temperature changes

PCB and Control Box Temperatures

What they are: Internal electronics temperatures.

Typical Values:

Normal operation: 30-50°C (86-122°F)
Warning: > 60°C (140°F)

Why it's important:

Indicates pump ventilation and ambient conditions
High electronics temperatures can trigger thermal protection
Useful for diagnosing overheating in enclosed installations

Motor Metrics

Speed (RPM)

What it is: Motor rotational speed in revolutions per minute.

Typical Range: 1000-4500 RPM (varies by model and control mode)

Why it's important:

Direct indicator of pump activity (0 RPM = pump off)
In Constant Speed mode, this is the controlled parameter
Correlates with flow rate (higher RPM = higher flow, generally)
Can reveal pump health (erratic RPM changes may indicate motor issues)

Power Draw

What it is: Electrical power consumed by the pump motor.

Why it's important:

Energy monitoring: Track operating costs
Efficiency analysis: Compare power vs. flow/head to evaluate system efficiency
Fault detection: Abnormal power draw can indicate:
Motor overload (too high)
Bearing wear (fluctuating)
Electrical issues (too low)

Monitoring Best Practices

1. Baseline Your System

When first installing or after system changes:

# Monitor for 5 minutes to establish baseline
alpha-hwr monitor --interval 2 > baseline.log

Record typical values:

Flow during normal operation
Head at typical flow
Temperature when fully warmed up
Power consumption averages

2. Watch for Anomalies

Flow Anomalies:

Sudden drop (< 50% of baseline) Check for blockage/closed valve
Gradual decline Check for scaling or sediment
Excessive flow (> 150% of baseline) Check for leaks or open bypass

Head Anomalies:

Sudden spike Air lock, blockage, or closed valve
Gradual increase Scaling or sediment buildup
Sudden drop System leak or bypass valve opened

Temperature Anomalies:

Not reaching target Heater issue or excessive heat loss
Fluctuating rapidly Water heater short cycling
Declining over time Check for heat loss in pipes

3. Optimize for Efficiency

Goal: Minimum flow and head that maintains comfort

Process:

Monitor temperature at furthest fixture
Gradually reduce setpoint (pressure/speed) until temperature just meets minimum
Set flow limit to prevent waste
Enable scheduling to run only when needed

Example Optimization:

from alpha_hwr import AlphaHWRClient

async with AlphaHWRClient("YOUR-DEVICE-UUID") as client:
    # Start with baseline
    await client.set_constant_pressure(3.0)  # 3.0 m initial

    # Monitor and verify comfort at all fixtures
    # If adequate, reduce gradually
    await client.set_constant_pressure(2.5)  # Reduce to 2.5 m

    # Continue until minimum effective setpoint found

4. Use JSON Output for Logging

# Log to file for long-term analysis
alpha-hwr monitor --format json >> pump_log_$(date +%Y%m%d).json

# Analyze later with jq or Python
jq '.flow_m3h' pump_log_20260130.json | awk '{sum+=$1; count++} END {print sum/count}'

System Diagnostics

Interpreting Common Scenarios

Scenario: No Flow, High Head

Flow: 0.00 m³/h
Head: 5.5 m
Speed: 3500 RPM
Power: 15 W

Diagnosis: Closed valve or complete blockage
Action: Check all valves in return line, verify no closed isolation valves

Scenario: Low Flow, Very High Head

Flow: 0.3 m³/h
Head: 4.8 m
Speed: 4000 RPM
Power: 28 W

Diagnosis: Partial blockage or severely restricted system
Action: Check for:

Sediment buildup in pipes
Partially closed balancing valves
Undersized pipe sections
Air trapped in high points

Scenario: High Flow, Low Head, High Power

Flow: 3.0 m³/h
Head: 0.5 m
Speed: 3800 RPM
Power: 38 W

Diagnosis: Oversized system or bypass open
Action:

Verify all bypass valves are closed
Consider flow limiting to reduce energy waste
Check for unintended parallel paths

Scenario: Normal Flow/Head, Excessive Power

Flow: 1.2 m³/h
Head: 2.5 m
Speed: 2800 RPM
Power: 45 W

Diagnosis: Motor/bearing issue
Action: Contact service - motor may need maintenance

CLI Commands for Monitoring

# Real-time monitoring
alpha-hwr monitor

# Compact single-line updates
alpha-hwr monitor --format compact

# JSON for logging/automation
alpha-hwr monitor --format json

# Custom update interval
alpha-hwr monitor --interval 5

# Get single snapshot
alpha-hwr monitor --format json | head -1

Python API Examples

Basic Telemetry

from alpha_hwr import AlphaHWRClient

async with AlphaHWRClient("YOUR-DEVICE-UUID") as client:
    telemetry = await client.get_telemetry()

    print(f"Flow: {telemetry.flow_m3h:.2f} m³/h")
    print(f"Head: {telemetry.head_m:.2f} m")
    print(f"Power: {telemetry.power_w:.1f} W")
    print(f"Temperature: {telemetry.media_temperature_c:.1f} °C")
    print(f"Speed: {telemetry.speed_rpm:.0f} RPM")

Continuous Monitoring with Analysis

import asyncio
from alpha_hwr import AlphaHWRClient

async def monitor_with_analysis(duration_seconds=60):
    async with AlphaHWRClient("YOUR-DEVICE-UUID") as client:
        flow_samples = []
        head_samples = []

        for _ in range(duration_seconds // 2):  # Sample every 2 seconds
            telemetry = await client.get_telemetry()

            flow_samples.append(telemetry.flow_m3h)
            head_samples.append(telemetry.head_m)

            await asyncio.sleep(2)

        # Calculate statistics
        avg_flow = sum(flow_samples) / len(flow_samples)
        avg_head = sum(head_samples) / len(head_samples)

        print(f"Average Flow: {avg_flow:.2f} m³/h")
        print(f"Average Head: {avg_head:.2f} m")
        print(f"Flow Stability: {max(flow_samples) - min(flow_samples):.2f} m³/h range")
        print(f"Head Stability: {max(head_samples) - min(head_samples):.2f} m range")

asyncio.run(monitor_with_analysis())

Understanding Pump Telemetry

Core Metrics

Flow Rate

Head Pressure

Performance Relationships

Pump Curve

Power Consumption

Temperature Metrics

Media Temperature

PCB and Control Box Temperatures

Motor Metrics

Speed (RPM)

Power Draw

Monitoring Best Practices

1. Baseline Your System

2. Watch for Anomalies

3. Optimize for Efficiency

4. Use JSON Output for Logging

System Diagnostics

Interpreting Common Scenarios

Scenario: No Flow, High Head

Scenario: Low Flow, Very High Head

Scenario: High Flow, Low Head, High Power

Scenario: Normal Flow/Head, Excessive Power

CLI Commands for Monitoring

Python API Examples

Basic Telemetry

Continuous Monitoring with Analysis

See Also