Gas Boiler Fitting. DIY or Professional Installation?

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Gas boiler fitting is a very complicated process that requires proper knowledge, skills, experience and license, of course. Before hiring a professional it is also highly important to check whether you are to have a special permit with local authorities. If you don’t do it, you risk spending much time and money, as in many locations they have special regulations about the boiler type that can be fitted based on carbon dioxide production and efficiency levels.

gas boiler fitting

Fitting Different Types of Gas Boilers

Today there are three main types of gas boilers offered on today’s market:

  • conventional (regular) boilers
  • sealed system boilers
  • combination (comb) boilers

If we speak about their fitting, they have different levels of difficulty.

Conventional ones require the fitting of a tank, a cylinder and a boiler itself. System boilers should be attached to the water and gas lines, according to the guidelines that are provided by the manufacturer of the chosen appliance. In case of system units, one should also pay special attention to proper venting in order to prevent the release of dangerous gases during the combustion.

Sealed system units don’t require the fitting of a separate tank, as the majority of vital parts are already contained in a boiler. However, some appliances still require the installation of a cylinder along with the boiler fitting. Water and gas lines should be tapped as well.

Combination (combi) boilers do not need a tank or a cylinder. Such systems should be installed to the provided directions and then attached to the lines.

Though most manufacturers provide detailed instructions, it still doesn’t mean that the units can be easily installed by an inexperienced person. To avoid possible negative consequences and complications, we suggest hiring a professional with experience in installation procedures.

Fitting Costs. How Much Will You Spend?

It is hard to say there is one certain amount of cash that is spent by everyone. There is no fixed sum, but there is a list of approximate expenses:

  • in case of 80% efficiency: if you are about to replace an old boiler, the installation costs will vary from $2,500 to $4,000
  • in case of 90-97% efficiency: if you are about to replace an old boiler, the installation costs will vary from $5,000 to $9,000

There is also a number of additional factors that influence the installation costs (they can go higher or lower):

  • professional old unit removal ranges from $300 and to $1,500
  • a new chimney liner is needed if you are upgrading to a boiler with higher efficiency level. This will cost about $300-$700 for gas boilers
  • units that are rated at 95 % efficiency and even higher are usually eligible for a $150 federal tax credit through Energy Star. Some places have other tax credits that curb the cost of high-efficiency systems.

In any case, there is always a chance to cut down on additional unexpected expenses, if you hire a professional, who’s well-acquainted with the gas boiler fitting procedure.