There are many reasons not to install a furnace yourself. Perhaps you just purchased a new home, built one from the ground up, or must suddenly replace your old heater while balancing other expenses. A DIY furnace installation won’t save you money. It can also be extremely dangerous. As a general rule, you should always hire a licensed and trained contractor for furnace installation.
Here are 8 reasons not to install your own furnace:
Some manufacturers supply furnaces to wholesalers, but not many. Furnace manufacturers and suppliers rarely sell heating equipment directly to consumers. Most of them work directly with HVAC installers, so product availability (and finding a reputable source) can be a problem.
An experienced technician knows where to find the right equipment and likely has a business relationship with a reputable supplier. In addition, other parts, such as gas connection fittings, exhaust pipes, a condensate pump, and a drain line may be needed, even if replacing the old unit with the same type. And, you’ll need tools like pliers, screwdrivers, drills, hammers, multimeters, tube cutters, and others (the exact equipment required depends on the furnace model).
Given the complexity of furnace installation and everything needed to accomplish it, you should never attempt it yourself.
Every state has its own rules and regulations. In California, installing a furnace or other major HVAC component requires pulling a building permit, which is issued by the city or county. A permit ensures a project is inspected and meets safety and structural standards. Generally, only a professional installer has the access and resources to obtain a permit, especially when installing a gas-powered appliance.
As a homeowner, you could also pull the permit. However, any agency overseeing the process will see you as the contractor. You’ll be liable for any issues with the installation (the municipality may require you to start over if there are questions about compliance, costing time and money). A contractor is familiar with the installation and inspection process, so they’ll approach the project with every legal requirement in mind.
From shutting off the old system to removing it to connecting the new furnace, a professional contractor understands the entire process. Installation also often involves custom cutting and fitting pipe, duct, and vent connections and ensuring everything is properly sealed. Do you know the best-sized PVC pipe for the exhaust or the right lengths and fittings for the gas connection? Or, do you have the proper wiring or electrical capacity for a new electric furnace? Forgetting or skipping any of these considerations can have dire consequences.
Most homeowners who try to install their furnaces don’t know how to perform a load calculation. Improper sizing can result in inefficient heating; plus, it can strain a furnace, leading to frequent repairs or early replacement. A trained contractor can determine the best-sized furnace based on the square footage of your home, the number of rooms, window sizes, the quality of insulation, and many other factors. The size and condition of ductwork are also important considerations.
Hooking a furnace up to a natural gas line requires a permit. Any mistakes can lead to a gas leak that can trigger an explosion and destroy your home. Using the wrong fittings or not properly securing connectors with the right tools can have devastating results. Professionals have the tools to secure and seal gas lines and detect potential leaks.
No matter what type of furnace you have, the electronics, blower, and ignition system require electricity. In most cases, the heater requires a dedicated circuit. A technician can install one and configure the hot, neutral, and ground wires. They also know where to mount the switch and other control features.
If you’ve never attempted furnace installation before, chances are your knowledge of thermostat wiring is limited. The more complex a thermostat, the more wires it has. Even a basic modern system may have up to four wires and those with advanced controls, multi-stage heating and cooling, etc. may require as many as 10 wires. Each wire must be fit into the correct terminal for the system to run properly.
Furnace manufacturers typically require a professional to install their equipment. This is often explicitly stated in the terms of the warranty. Therefore, installing a furnace yourself can void the warranty, which can have costly consequences if you make a mistake or something randomly goes wrong. You’ll have to pay the full cost of repairing or replacing the unit.
Also, your home insurance may not cover damage due to DIY furnace installation. Or, the company can cancel your policy if it finds out the work was done without a permit.
A good reason to hire a professional installer is they’ll ensure your furnace works. The slightest mistake or lack of precision can lead to combustion problems, which can prevent the unit from effectively heating your home. These can also cause carbon monoxide leaks, which can lead to illness and death. The system can be strained by operational, ventilation, and air distribution problems as well, so it may require frequent and costly repairs, erasing any savings you thought you’d achieved with a DIY installation.
NexGen is a residential heating installation and replacement company serving Southern California. Fully licensed and insured, our technicians install many types of heating equipment, including single- and two-stage multi-speed units and modulating variable-speed systems. Comprehensive maintenance plans and extended warranties are available. To request professional furnace installation and a free evaluation and estimate, contact us online or call (805) 301-6788 today.