Gas Boiler Installation

  • 10-20 hours
  • Advanced
  • 5,000-8,000
What You'll Need
Gas Boiler
Pipe Wrenches
Boiler Accessories

A gas boiler installation is a complex procedure and many states require you to be licensed or certified for the installation to conform to building codes. Before you begin, check whether you need a permit with your local authorities, otherwise you may be wasting your time. Some states may also have regulations about the type of boiler you can install based on efficiency and carbon dioxide production levels.

Step 1 – Choose Your Boiler

The gas boiler that you install will depend on personal budget and preference, as well as the type of gas supply that you have in your home. Before buying a boiler, you should research the possibilities thoroughly and check with your local authorities as to what regulations there are regarding the type of boiler you require, or the installation process in your area. Once you have chosen, you will need to order any accessories such as vents, pumps or valves that are not included in the original purchase.

Step 2 – Prepare Installation Area

Before the boiler arrives, check that the area you want to install it in is suitable. You will need water, gas and electrical supplies available, and no combustible items should be stored in the same area. There also needs to be somewhere to install an external vent and you will need easy access for future regular maintenance visits.

Step 3 – Unpack and "Dress" Boiler

When your boiler arrives, remove it and any enclosed accessories from its packaging. To do so, you will need to remove the screw securing the boiler to the wooden pallet underneath. Unpack the valves and accessories and collect any you bought separately. "Dress" the boiler by installing all of the accessories in the correct places.

Step 4 – Install Water Piping

Your boiler needs to have a feed and return for the hot water system. Normally, flo-checks are installed on the feed side and circulators on the return. However, zone valves are an acceptable option if you prefer them. It's important to make sure that you use the correct width of piping and enough circulators to cope with the size of the system. If too few circulators are used, you will have persistent problems with the pump.

Step 5 – Install Venting and Flue

A gas boiler must have sufficient venting for safe operation. The type of venting required will depend on your boiler, so check the installation instructions that came with it for the manufacturer's recommendation.

Step 6 – Connect Gas Supply

The connection of the gas supply will vary slightly depending whether you use propane or natural gas, so you will need to check the manual for exact details. If you're not licensed to work with a gas supply, consider employing a professional to complete this stage safely.

Step 7 – Fill and Start

When all of the connections have been made correctly, turn on the water supply to the boiler and use the automatic feed valve to obtain the recommended operating pressure advised. Normally this will be between 18 and 22 psi. A licensed professional needs to adjust the carbon dioxide output and verify that the installation meets the required standard before a service technician gives the go ahead for use.