Boiler Service in Dover

How Hydronic Heating Systems Work

A boiler is the heart of a hydronic heating system. It circulates heated water or steam through a closed loop of pipes to radiators, baseboard heaters, or radiant floor tubing. Unlike forced-air systems, there’s no ductwork and no circulating air, which means fewer drafts and more even heat distribution throughout the home.

Proper sizing allows the system to maintain steady heat through a Strafford County winter without unnecessary cycling and premature component wear.

Zone heating is one of the practical advantages of a boiler-based system. Because the distribution loop can be divided into independently controlled circuits, different areas of the home can be held at different temperatures without running the full system at full output.

Pre-season maintenance gives the system attention before sustained cold weather arrives. A no-heat failure during winter calls for an emergency service call rather than waiting for the problem to correct itself.

Common Boiler Problems & the Repair-vs-Replace Decision

Schedule service if you notice any of these boiler problems:

• No heat or insufficient heat
• Banging or kettling noises
• Unexplained pressure drops
• Pilot light or ignition failures
• Water leaks around the unit
• Steadily rising fuel bills

None of these problems should be deferred into the heating season.

Carbon monoxide deserves its own mention. It’s an odorless, colorless byproduct of incomplete combustion. A cracked heat exchanger or a blocked flue is a safety emergency, not a maintenance item to schedule around convenience. If you have any reason to suspect a combustion issue, leave the home and call for service immediately.

The choice between boiler repair and replacement depends on the system’s condition, the specific failure, the work required, and the replacement equipment available for the home. Repeated breakdowns and components that are no longer manufactured also weigh into that decision.

When Repair Makes Sense

Repair is a practical choice when the problem is isolated, the rest of the system is in sound condition, and the required replacement parts remain available. Examples include a failed circulator pump, ignition component, control, or pressure-related component that can be replaced without rebuilding the system. A diagnosis identifies the failed part and helps you compare the scope of the repair with the condition of the boiler as a whole.

When Replacement Is the Better Answer

Replacement deserves consideration when the boiler needs repeated repairs, has extensive deterioration, or relies on parts that are difficult to obtain. The available replacement equipment, required output, existing distribution system, and whether the home uses steam or a water-based system also affect the decision.

AFUE should be considered alongside proper sizing rather than used as the only basis for selecting a replacement.

Boiler Fuel Types, Output & AFUE Ratings

Residential boilers are classified partly by their energy source and whether they produce steam or circulate heated water. Annual Fuel Utilization Efficiency, or AFUE, measures the ratio of annual heat output to the fuel energy the equipment consumes. Fuel type affects the applicable product class, efficiency standard, and compatibility with the home’s existing system.

Common residential boiler energy sources include:

• Electricity: Equipment powered by single-phase electric current
• Natural gas or propane: Gas-fired equipment connected to the appropriate fuel supply
• Home heating oil: Oil-fired equipment supplied by an on-site storage system
• Combined energy: Equipment designed to use electric current and fuel

Federal minimum efficiency standards in effect as of 2026 require gas-fired hot-water boilers to achieve at least 84% AFUE. Oil-fired hot-water boilers must achieve at least 86% AFUE. These minimums apply to specific federal product classes, so a steam boiler shouldn’t be compared directly with a hot-water boiler solely by looking at the AFUE number.

Output must also match the home’s calculated heat loss. Square footage alone doesn’t determine boiler size because insulation and window area affect how much heat the building loses. Matching output to that calculation helps avoid an undersized unit that struggles during cold weather or an oversized boiler that repeatedly short-cycles.