Generac Generators: Models, Costs, Reliability & Buying Guide

Generac Generators at a Glance

Are Generac Generators Good?

Generac generators are a strong mainstream choice for residential standby power, particularly where there is good local dealer and service support.

The brand's practical strengths include:

• Wide range of residential standby generators
• Established US dealer network
• Natural-gas and propane options
• Automatic transfer equipment
• Load-management systems
• Remote monitoring
• Replacement-parts availability
• Strong installer familiarity

That does not mean Generac is automatically the best choice for every house.

There is not enough independent population-level failure data to credibly claim that Generac is universally more reliable than Kohler, Cummins, Briggs & Stratton or every competing brand.

With a permanently installed generator, the installer is effectively part of the product.

A correctly sized Generac installed by a competent dealer with good local service support can be a very different ownership experience from the same generator installed poorly or supported by a weak contractor.

What Types of Generators Does Generac Make?

Generac sells several different types of backup-power equipment.

Generac Home Standby Generators

Home standby generators are permanently installed outside the house and connected to the home's electrical system.

When utility power fails, a properly configured standby system can:

1. Detect the outage.
2. Start the generator.
3. Transfer the selected household loads onto generator power.
4. Continue supplying power until utility service returns.
5. Transfer the house back to utility power and shut the generator down.

These are the Generac systems most homeowners mean when searching for a whole house Generac generator.

Compare current Generac standby generator sizes and models →

Generac Portable Generators

Portable generators are manually deployed rather than permanently installed.

They can provide much cheaper emergency backup where automatic whole-home power is not required.

Read the portable generator guide →

Generac Inverter Generators

Inverter generators are portable units designed around quieter operation, portable power and cleaner electrical output.

They serve a different purpose from a permanently installed standby generator.

Read the inverter generator guide →

Which Generac Generator Size Do You Need?

Do not choose a Generac generator from house square footage alone.

Two homes of identical size can have very different backup-power requirements.

The loads that matter include:

• Central air conditioning
• Heat pumps
• Electric heat
• Electric water heaters
• Well pumps
• Sump pumps
• Pool equipment
• Electric cooking
• Refrigeration
• Medical equipment
• EV charging
• Other large motor loads

The correct process is:

1. Decide what you want powered during an outage.
2. Calculate the running load.
3. Account for motor starting requirements.
4. Determine which high-demand loads need to operate simultaneously.
5. Decide whether load management will be used.
6. Select a generator with sufficient output on the fuel you will actually use.

Do not buy the generator first and try to make the house fit it afterwards.

Calculate your required generator size →

Compare Generac standby generator sizes →

Popular Generac Home Standby Generator Sizes

Generac's residential standby range covers smaller essential-load systems through larger whole-home configurations.

Common buying categories include:

• Smaller essential-load systems
• Mid-range residential standby generators
• 18-22 kW-class systems
• 24-28 kW-class systems
• Larger liquid-cooled generators

A headline model size should not be treated as the complete specification.

Rated output can vary between natural gas and liquid propane, so compare the actual fuel-specific output of the model being quoted.

That becomes particularly important when your calculated load is close to the generator's maximum capacity.

See current Generac models, sizes and specifications →

Generac Natural Gas vs. Propane

Many Generac residential standby generators can operate on either natural gas or liquid propane.

Natural Gas

Natural gas can be attractive because it provides a utility-fed fuel supply without requiring a large storage tank.

Potential advantages include:

• No manual refuelling
• No large propane tank
• Convenient extended operation while gas service remains available

However, the property's gas system must be able to supply the generator.

Depending on the installation, that can require:

• Larger gas piping
• Meter upgrades
• Regulator changes
• Utility coordination

Propane

Propane stores the backup fuel on the property.

Potential advantages include:

• Works where natural gas is unavailable
• Known on-site fuel reserve
• Independence from the natural-gas network

The trade-off is storage capacity.

During a prolonged outage, runtime is limited by the amount of propane available and the generator's fuel consumption.

The same Generac model may also have different rated power output on natural gas and propane.

Always size the generator using the specification for the fuel you intend to use.

Generac Dealers and Installers

For a permanent Generac standby system, the quality of the installer matters almost as much as the generator you buy.

A competent installer should be able to handle or coordinate:

• Load calculation
• Generator sizing
• Site assessment
• Electrical work
• Natural-gas or propane connection
• Automatic transfer switch installation
• Load management
• Permits
• Generator commissioning
• Warranty requirements
• Ongoing maintenance

Before hiring a Generac installer, ask:

1. Who performs the load calculation?
2. Why are they recommending this generator size?
3. What is the model's output on your chosen fuel?
4. Is the transfer switch included?
5. Is load management required?
6. Are permits included?
7. Does the quote include all electrical and fuel work?
8. Who handles warranty service?
9. Do they provide annual maintenance?
10. What happens if the generator fails during a major regional outage?

The cheapest installer is not necessarily the cheapest system to own.

Compare generator installers and quotes →

Generac Automatic Transfer Switches

The automatic transfer switch allows a Generac standby generator to restore household power without the homeowner manually connecting the generator.

During an outage:

1. Utility power fails.
2. The generator starts.
3. Transfer equipment isolates the appropriate loads from the utility.
4. Generator power is supplied to the house.
5. Utility power returns.
6. The system transfers back and the generator shuts down.

Different Generac installations can use different transfer-switch and load-management configurations.

Do not choose the generator and transfer switch independently.

Read our automatic transfer switch guide →

Generac Load Management

Load management can reduce the amount of generator capacity required for a house.

Consider a home with:

• Two air conditioners
• Electric water heater
• Electric dryer
• Pool equipment

Sizing the generator for every heavy load to operate simultaneously can push the project into a much larger generator class.

A managed system can temporarily prevent lower-priority equipment from running while higher-priority loads are using generator capacity.

That can potentially:

• Reduce required generator size
• Reduce equipment cost
• Reduce fuel consumption
• Avoid unnecessary oversizing

For many houses, smarter load management is better than simply buying the biggest generator available.

Generac Mobile Link and Remote Monitoring

Compatible Generac systems can provide remote generator monitoring.

Depending on the generator and connectivity configuration, monitoring can include:

• Generator status
• Exercise activity
• Maintenance reminders
• Fault notifications
• System alerts

Remote monitoring can be particularly useful for:

• Second homes
• Rental properties
• Frequently vacant properties
• Homeowners who travel

It is a useful ownership feature, but it should not outweigh generator sizing, installation quality or local service support when choosing a system.

Generac Warranty

Generac warranty terms can vary by model, product generation, purchase date and manufacturer promotion.

Before buying, verify the warranty for the exact generator being quoted.

Check:

• Standard warranty duration
• Parts coverage
• Labour coverage
• Registration requirements
• Travel or service limitations
• Extended coverage
• Promotional coverage
• Installation requirements
• Local warranty provider

A long written warranty is only valuable if somebody locally is prepared and able to perform the service.

Generac Maintenance

Generac standby generators require routine maintenance.

Depending on the model and operating conditions, maintenance can include:

• Engine oil
• Oil filter
• Air filter
• Spark plugs
• Starting battery
• Exercise-cycle checks
• Fuel-system inspection
• General inspection
• Monitoring and fault checks

Follow the maintenance schedule for the exact model rather than a generic interval found online.

Before choosing an installer, ask what annual servicing costs and whether the company provides service during prolonged or widespread outages.

Are Generac Generators Reliable?

Generac is an established residential standby-generator manufacturer with a large installed base and dealer network.

However, there is not enough credible public failure-rate data to assign all Generac generators a meaningful universal reliability percentage.

Long-term reliability depends on more than the logo on the enclosure.

Important variables include:

• Generator model
• Installation quality
• Correct sizing
• Fuel supply
• Operating hours
• Climate
• Maintenance
• Battery condition
• Transfer equipment
• Local service support

Our practical conclusion is simple:

Generac belongs on the shortlist for residential standby power, but the installer, system design and service network should be evaluated alongside the generator itself.

Common Generac Complaints

Owner and installer discussions commonly involve issues such as:

• Dealer support
• Warranty handling
• Maintenance
• Service availability
• Battery problems
• Fuel-supply problems
• Installation faults
• Individual component failures

Individual reports are useful for discovering questions to ask.

They should not be converted into a made-up brand-wide failure rate.

Some problems blamed on the generator itself can actually originate from incorrect sizing, inadequate fuel supply, installation quality, transfer equipment or poor maintenance.

Generac vs. Kohler

Generac and Kohler are two of the most commonly compared residential standby-generator brands.

Generac's practical strengths include:

• Broad residential range
• Large installer network
• Extensive residential familiarity
• Load-management ecosystem
• Monitoring options

Kohler can be equally compelling where the local Kohler dealer and service network are stronger.

Compare:

• Correctly sized models
• Natural-gas output
• Propane output
• Transfer equipment
• Load management
• Warranty
• Monitoring
• Installed price
• Installer quality
• Local service support

The best brand can therefore differ from one market to another.

Compare Generac vs. Kohler →

Should You Buy a Generac Generator?

Generac should be on the shortlist for most mainstream US residential standby-generator projects.

A Generac makes particularly good sense when:

• You want automatic permanent backup power
• Natural gas or propane is suitable
• The range contains a correctly sized generator for your load
• A reputable local Generac installer is available
• The complete installed quote is competitive
• Ongoing service is available

We would be more cautious when:

• Local Generac service is poor
• Another brand has significantly stronger dealer support nearby
• The installer cannot explain the load calculation
• The generator appears unnecessarily oversized
• The quote does not clearly state what is included
• Warranty responsibility is unclear

Do not buy a standby generator from the brand name alone.

Buy the complete backup-power system:

generator + sizing + fuel + transfer equipment + installation + warranty + service.

How to Choose a Generac Generator

Use this order:

1. Calculate Your Backup Load

Start with the loads you actually want powered.

Use our Generator Size Calculator →

2. Decide Your Backup Strategy

Choose between:

• Essential loads
• Managed whole-home backup
• Broad whole-home backup

3. Choose the Fuel

Determine whether the system will use:

• Natural gas
• Propane

4. Check Fuel-Specific Generator Output

Do not assume the headline kW number applies equally to both fuels.

5. Compare Appropriate Generac Models

Once you know the required capacity, compare the models that can actually meet it.

Compare Generac standby generators →

6. Compare Installers

Get multiple quotes where practical.

Find and compare generator installers →

7. Compare Complete Installed Price

Include:

• Generator
• Transfer switch
• Load management
• Electrical work
• Fuel work
• Permits
• Warranty
• Maintenance

8. Compare Another Brand

Where local availability allows, compare the proposed Generac system against at least one credible Kohler, Cummins, Briggs & Stratton or Champion alternative.

The exercise tests whether Generac is genuinely the best system for your house rather than simply the first quote you received.

Find a Generac Generator Installer

For a standby generator, the installation should be considered part of the purchase rather than an afterthought.

Compare contractors on:

• Generator sizing
• Experience with Generac systems
• Electrical scope
• Fuel-system scope
• Permit handling
• Transfer equipment
• Warranty support
• Maintenance
• Total installed price

Compare local generator installers →

Next Steps

If you're actively considering a Generac, do these three things next:

1. Calculate the capacity your house actually requires.
2. Compare the Generac models that satisfy that requirement.
3. Get more than one complete installed quote.

Calculate generator size →

Compare Generac models →

Compare generator installers →