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Air-Cooled Diesel Generator- The Definitive Guide 2024

Table of Contents

Introduction of Air-Cooled Diesel Generator

Air-cooled diesel generators also called portable diesel generators are one type of small power-generation equipment.

Typically, the power range of air-cooled diesel generators is from 2kW/2KVA to 16kW/16kVA.

air-cooled silent diesel generator

How is The Air-Cooled Diesel Generator Cooling?

Air-cooled diesel generators equipped with the air-cooled system, cooled by air and heat dissipation.

The working principle is the air-cooled diesel engine takes in cooler air from the atmosphere when working, blowing this air internally across the generator set, keeping the generator from overheating.

They use air as a cooling medium to transmit the heat from the heated parts of the diesel engine, and this cooling method consists of a heat sink fan and a guide cover.

air-cooling fan

How Does The Air-Cooled Diesel Generator Generate Electricity?

Through the diesel fuel, the diesel engine is the prime mover to drive the generator power.

air-cooled diesel engine

The whole generator is generally composed of a diesel engine, alternator, control panel, fuel tank, starting battery, protection devices, and other components.

What Are The Different Types of Air-Cooled Diesel Generators?

Air-cooled diesel generators are available in silent and open-frame type.

air-cooled silent diesel generator
Silent Type
  • Silent generators, as the name suggests, silent generators have been fully enclosed in a robust soundproof enclosure, which makes for a quieter design and makes it ideal for providing backup power to a home or small business. Perfect solution to get your home or business through blackouts or load-shedding periods.
  • Open-frame generators, as the name suggests, open frame generators are manufactured without canopies. The open design allows for greater airflow with better heat dissipation. Particularly suitable for hot working environments
air-cooled open-frame diesel generator
Open-Frame Type
Silent generator: lower noiseOpen-frame: noisy
Silent generator: larger fuel tank, longer running timeOpen-frame: small fuel tank
Silent generator: weatherproofOpen-frame: not rainproof design
Open-frame generator: recoil and electric start method 
Open-frame generator: convenient maintenance and access 
Open-frame generator: better heat dissipation 
Silent and open-frame generators: durability 

Power Range of Air-Cooled Portable Diesel Generators

WALT Power offers a minimum power range of 2kW/2kVA to 16KW/16kVA air-cooled diesel generators in silent & open frame generators.

This supply range meets the needs of the vast majority of individuals, families, and on-site mobile power.

air-cooled open-frame diesel generator onsite working

Application Fields of Air-Cooled Portable Diesel Generators

Air-cooled diesel generators can be widely used in homes, hotels, shops, UPS backups, offices, power tools, construction sites, agriculture, medical clinics, event parties, etc.

Can be moved at any time, easy to carry, strong output power

Benefits of Air-Cooled Diesel Generators

  • Purchase costs are low, if the budget is limited, you can choose the air-cooled diesel generator which can meet most usage scenarios.
  • Since there isn’t a cooling water radiator system for the air-cooled diesel generator, thus the maintenance is simple and costs are low.
  • Compact size, reduced packaging, shipping, and less space are required to house the unit.
  • Lightweight, in most cases, the air-cooled diesel generator can be moved by a single person. The user doesn’t need a forklift to move the generator, saving the money.

Air-Cooled Portable Diesel Generator Buying Guide:

Buying guide

Before choosing the right model of the air-cooled diesel generator, consider what features & functions are most important to you.

Below, we’ll discuss some of the most important considerations that can help you make a decision.

Genset Output Power Selection

The most important thing when purchasing a generator set is to determine the required output power of the generator set. It can be calculated according to the purpose of the generator set.

air-cooled generators

For example:

3kW-5kW: entertainment, power tools, small appliances, lights, heating and cooling, and medium-sized appliances (air-conditioner, refrigerator, oven, microwave oven, mixer, etc)

6KW-10KW: emergency power supply, heating and cooling, large electrical appliances, water heaters.

10KW-16KW: Emergency backup power for the entire home.


ApplianceWatts (kW)
Blender500 (0.5kW)
Coffee maker900–1200 (0.9-1.2kW)
Clothes washer350–500 (0.35-0.5kW)
Clothes dryer1800–5000 (1.8-5kW)
Dishwasher1200–2400 (1.2-2.4kW)
Dehumidifier785 (0.785kW)
Ceiling Fans65–175 (0.065-0.175kW)
Window Fans55–250 (0.055 – 0.25kW)
Furnace Fans750 (0.75kW)
Hair dryer1200–1875 (1.2-1.875kW)
Heater (portable)750–1500 (0.75-1.5kW)
Clothes iron1000 –1800 (1-1.8kW)
Microwave oven750 – 1100 (0.75 -1.1kW)
Laptop50 (0.05kW)
Refrigerator (frost-free, 16 cubic feet)725 (0.725kW)
19″ Television65–110 (0.065-0.11kW)
27″ Television113 (0.113kW)
36″ Television133 (0.133kW)
53″-61″ Projector170 (0.17kW)
Flat screen Television120 (0.12kW)
Toaster800 – 1400 (0.8 -1.4kW)
Vacuum cleaner1000–1440 (1-1.44kW)
Water heater (150 liters or U.S 40 Gal)4500–5500 (4.5-5.5kW)
Water pump (deep well)250–1100 (0.25-1.1kW)
Central Air Conditioner 24,000 BTU3800 (3.8kW)
Central Air Conditioner 10,000 BTU3250 (3.25kW)
Window Air Conditioner 10,000 BTU900 (0.9kW)
Window Air Conditioner 12,000 BTU3250 (3.25kW)
Furnace Fan Blower800 (0.8kW)
Tankless Water Heater18000 (18kW)
CFL Bulb – 40 Watt Equivalent11 (0.011kW)
CFL Bulb – 60 Watt Equivalent18 (0.018kW)
CFL Bulb – 75 Watt Equivalent20 (0.02kW)
CFL Bulb – 100 Watt Equivalent30 (0.03kW)
Band Saw – 14″1100 (1.1kW)
Belt Sander – 3″1000 (1kW)
Chain Saw – 12″1100 (1.1kW)
Circular Saw – 7-1/4″900 (0.9kW)
Circular Saw 8-1/4″1400 (1.4kW)
Disc Sander – 9″1200 (1.2kW)
Drill – 1″1000 (1kW)
Drill – 1/2″750 (0.75kW)
Drill – 1/4″250 (0.25kW)
Hedge Trimmer450 (0.45kW
If you cannot find the wattage on the appliance, check to see if the unit lists amperes instead.
If so, you can find the wattage by multiplying amperes by voltage using the formula:

KW =Watts/1000

If you want to know the kW of the appliance, you just need to use total watts/1000. Such as 5kW = 5000 Watts/1000.)

KW =(VOLTS x AMPS)/1000

If you have a device listed at 16 amps that uses 220 volts, you will have a wattage of 3.52KW (16 x 220 = 3,520)/1000.

Purchase Budget

budget calculation

The air-cooled diesel generator you choose will also ultimately depend on your purchase budget.

Before you start to purchase a generator, it’s important to know the budget you have to work with.

Generators come in a wide range of prices, with portable air-cooled diesel generators generally more affordable and water-cooled backup generators more expensive.

Select Genset Type

air-cooled open-frame diesel generator

WALT Power offers both open-frame and silent air-cooled diesel generators for different applications & budgets.

The open-frame models have better heat dissipation and the silent models are quieter. Both of them can meet your power needs.

Genset Voltage/Frequency/Phase


In 50Hz, most single-phase generators use 220v, 230v, 240v AC voltage.

In 60Hz, most single-phase generators use 110v, 220v, 230v AC voltage.

In 50Hz, most three-phase generators use 380v, 400v, 415v AC voltage.

In 60Hz, most three-phase generators use 220v, 230v, 460v, 480v AC voltage.

Thus, make sure the generator you choose matches the voltage ratings of the item you want to run.

You can contact a local electrician to get accurate information.

Genset Dimension & Installation

Genset installation

The overall size of the air-cooled generator set is compact, but due to different power and styles, the size of each model will vary.

Make sure that the installation space of the generator set is reserved for sufficient air intake and ventilation to ensure heat dissipation.

In addition, diesel power generation cannot be installed indoors.

Genset Fuel Choose

Add Diesel Fuel

Usually, air-cooled diesel generator’s diesel fuel is available in two different grades as well as a mix (as in “cold weather mix” of #1 and #2):

  • Diesel fuel grade #1 (D1);
  • Diesel fuel grade #2 (D2); and
  • Winterized diesel (a blend of #1 and #2 diesel fuels).

These different grades are compatible with any diesel engine, which means you can use one during the winter and another during the summer without problems.

Genset Start Methods

Air-cooled diesel generators provide recoil start, electric start, and auto start in three ways.

Usually, less than 5kW open-frame generators can use recoil start or electric start.

For the silent diesel generator, we recommend equipping with an electric start for all models that will be more convenient.

Recoil start: also called plural recoil starts.

recoil start of air-cooled diesel geenrator

A method of starting an internal combustion engine by pulling a rope so that it uncoils around the end of the crankshaft, spinning it to crank the engine.

Electric start: Rather than requiring you to pull-start the engine, an electric start simply requires that you turn a key to start your generator.

electric start of air-cooled silent diesel generator

Automatic start: also called ATS (automatic transfer switch).

Automatic transfer switch ATS

It can achieve fully automatic start/stop when the mains power fails or is normal, without manual operation, and is very convenient for daily use.

But if the generator set is not used for a long time, it is recommended to turn off this function.

Low Oil Protection

Prevents small engines from running below the critical oil level to avoid engine damage.

All of WALT Power’s air-cooled diesel generators are equipped with this protection.

Fuel Gauge

fuel gauge

When the generator has a fuel gauge, the users easily see how much fuel it has left to know when to refuel.

Multi Outlets

multi outlets

Equipped with multiple waterproof outlets & plugs on WALT Power’s air-cooled diesel generators allows you to run more than one device at a time.

Through safely plug in multiple appliances and spread out the wattage usage.

Wheel Kits

wheels kits

Not all generators manufactured by WALT Power’s air-cooled diesel generators come standard with wheels, this kit can be purchased as an option.

Be sure to consider the charge of the wheel kit if sold separately.


China generator manufacturer and supplier, WALT Power provides generator spare parts, alternator covers, power cords, and transfer switches to meet any emergency power needs.

Genset Maintenance

generator maintenance

Regular maintenance and inspection of the air-cooled diesel generator is very important.

To ensure your generator is in good working condition and long service life

The following are the basic daily inspection steps for the air-cooled diesel generator:

  1. Overall condition/appearance of equipment (panel, leaks, loose wires)
  2. Fuel filter
  3. Lubricating oil level and viscosity
  4. Air-filter
  5. Battery connection wires
  6. Fuel capacity


  • Every month start 1 to 2 for the diesel generator and run 10 minutes at least.
  • If not used for a long time, please remove the battery connection cable.
  • Before using the generator set again, replace the fuel, and engine oil, and charge the battery.


  • The generator should be placed outdoors in a protective enclosure, where sufficient air for cooling and ventilation is available in an unobstructed manner.
  • The generator should be placed on a level surface, which is non-combustible and non-conducting, a little above ground level to prevent contact with rising water levels.
  • Follow the directions supplied with the generator.
  • To avoid electrocution, keep the generator dry and do not use it in rain or wet conditions.
  • Operate it on a dry surface under an open canopy-like structure, such as under a tarp held up on poles.
  • Do not touch the generator with wet hands.
  • Plug appliances directly into the generator or use a heavy-duty outdoor-rated extension lead that is rated in watts or amps at least equal to the sum of the connected appliance loads.

Buying And Contact

You can contact us in many ways:

You can go to our website (URL: and drop us a message

You can email us:

You can send online messages through WhatsApp at 008618717996108

Our Contact is: +8618717996108


All in all, Walt Power will not fail you or your power needs.

Your air-cooled diesel generators will provide continuous onsite electricity for your home or business.

All our products are made with reliable materials and components, and we test each generator so that you do not have to, providing the clients with the best products in the market.

Ke Wong

Ke Wong

Hey, I’m Ke Wong joined WALT POWER in 2011. I spent a dozen years focused on generator set & load bank technology and solutions for the power & energy industry. WALT Power is a reliable & leading manufacturer & supplier in China, as a business director, I am so proud of our knowledge is more and more popular not only for engineers, and generator distributors but also for end-users. Hope you are enjoying our article, if any questions or comments welcome to send me sales at