**Q&A | Common Questions for Beginners with Home Espresso Machines**
Many beginners using semi-automatic espresso machines encounter various challenges, such as:
- How to choose the right setup?
- What are the differences between different types of machines?
- Should I choose a vibration pump or a rotary pump?
- How do I adjust extraction parameters?
- How do I clean the brew head?
To help you navigate these concerns, we have compiled answers to six of the most common questions.
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### **Q1: How to Choose a Heating System?**
An espresso machine’s structure is complex, but the two most crucial components are the boiler and the pump—one ensures temperature stability, while the other maintains consistent pressure. The most common heating systems include:
#### **Instant Heating Block**
- Heats up quickly.
- Ready for extraction shortly after turning on.
#### **Water Storage Boiler**
- Provides more stable temperature and better steam frothing.
- Supports continuous brewing.
- Available in single-boiler, dual-boiler, or heat exchanger models.
**Tip:** Instant heating blocks are ideal for those seeking quick morning coffee, like office workers. If you prioritize flavor consistency and continuous brewing, opt for a water storage boiler—dual boilers offer the best performance.
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### **Q2: Should I Choose a Vibration Pump or a Rotary Pump?**
The pump type affects extraction stability and crema production. Generally:
#### **Vibration Pump**
- Smaller and more affordable.
- Suitable for beginners using home machines.
#### **Rotary Pump**
- Quieter, provides more stable pressure, and is more durable.
- Recommended for those with a higher budget.
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### **Q3: What Are the Differences Between Various Brew Heads?**
The brew head connects the machine, boiler, and portafilter, directly impacting flavor extraction. Here are the main types used in Gemilai machines:
#### **Composite Brew Head**
- Integrated with the extraction boiler in an up-down structure.
- Zero distance between the water path and boiler, reducing temperature loss.
- Water circulation heat exchange ensures stable and precise temperature control.
#### **Classic E61 Brew Head**
- Features heat exchange, siphon insulation, mechanical pre-infusion, and high thermal conductivity from pure copper.
- Uses the heat siphon effect to maintain consistent temperature and stable extraction.
#### **Saturated E61 Brew Head**
- Connected horizontally to a 300ml PID-controlled water storage boiler.
- The integrated design eliminates temperature fluctuation.
- Extraction temperature is visible and adjustable.
#### **Thermal Balance Brew Head**
- Equipped with a PTC heating element.
- Reduces temperature loss from water traveling through pipes.
- Ensures consistent extraction temperatures.
#### **58mm Commercial Extraction System**
- Features a 58mm commercial portafilter and metal brew head.
- High-density, single-layer dispersion screen for even water distribution.
- A signature design of Gemilai, bringing commercial standards into home machines.
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### **Q4: Why Choose a 58mm Portafilter?**
With the same amount of coffee grounds and extraction time, a 58mm portafilter allows:
- A thinner coffee puck, increasing the surface area in contact with water.
- Better water penetration and more efficient extraction.
- A professional, café-level coffee experience when paired with the 58mm commercial extraction system.
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### **Q5: How to Adjust Extraction Parameters?**
Extraction quality can be assessed by flow rate:
- **Over-extraction** → Slower flow rate.
- **Under-extraction** → Faster flow rate.
- **Final judgment** → Determined by taste.
#### **Standard Extraction Parameters:**
- **Coffee Dose:**
- Single Espresso: 9-12g
- Double Espresso: 17-20g
- **Water Temperature:** 194-205°F
- **Grouphead Pressure:** 9-12 bar
- **Extraction Time:** 25±5 seconds
- **Powder-to-Liquid Ratio:** 1:2 to 1:2.5
*Note: These parameters serve as a guideline. Adjustments should be made based on the machine, coffee type, and personal taste preferences.*
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### **Q6: How to Clean the Brew Head?**
Regular cleaning extends the lifespan of the machine and ensures optimal coffee flavor. Prepare the following tools:
- Cleaning brush
- Clean cloth
- Cleaning mat
**Tip:** Follow your machine’s maintenance instructions for the best results.
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### **Gemilai: Bridging Commercial Standards with Home Machines**
Gemilai is committed to bringing professional-grade technology into home espresso machines, continuously refining design and user experience to elevate coffee brewing at home.
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