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Oil or Gas Boiler Replacement

Installed correctly, new oil or gas boiler can cut utility expenses while improving comfort.

Preparation
All accessible piping, radiators, and other components shall be inspected for damage or asbestos, and any observed problems shall be reported to the homeowner with recommendations for remediation before proceeding with the work. Alternately, in the case of hydro coil forced-air heating systems, the duct system shall be inspected, and any damaged, disconnected, undersized, unsupported, or overly long ducts shall be repaired or replaced.
Equipment shall be selected and sized in accordance with the Air-Conditioning Contractors of America (ACCA) manuals J and S.
Installation
An ENERGY STAR-certified, high-efficiency, sealed-combustion, direct-vent boiler shall be installed.
The boiler shall be installed in accordance with the ANSI/ACCA Standard 5 HVAC Quality Installation Specification.
For improved efficiency, the boiler shall include a multi-stage or modulating burner with adjustable output to better match heating loads, reduce the number of on-off cycles (and cycling losses), and allow operation for longer hours at lower firing rates.
The boiler shall be equipped with electronic controllers, which can increase equipment life, improve boiler efficiency, and enhance comfort by adjusting boiler water temperature, creating time-delay relays, performing automatic post-purge, preventing warm weather boiler operation, controlling the position of mixing valves, and controlling pump speeds.
The condensate line shall drain to a sewer or to outdoors. If condensate is drained to outdoors then the drain pipe shall be protected from freezing with either insulation or heat tape. Also a drain pan shall be installed under the boiler as a backup measure.
A minimum of a 20°F temperature differential shall be maintained between the supply and return temperatures under design conditions.
The temperature setting on the boiler reset curve shall be below the boiler’s high limit setting.
The warm weather shutoff shall be verified to be set at a high enough temperature to prevent no-heat situations during the swing seasons.
An outdoor reset sensor shall be placed away from any exhaust vents including kitchen, bath, dryer, and mechanical system vents and it shall not be in direct sunlight during any portion of the day. For condensing boilers, an outdoor reset control shall be installed matching system output to actual load and a recommendation shall be provided to homeowners to not use a night-time temperature setback strategy. Settings for the boiler reset curve and flow rates shall be selected to optimize the performance of the system and to ensure that the return temperatures are low enough to promote condensing.
Where present, the gas line shall be tested for leaks and a combustion safety test shall be performed after installation is complete.
If installing a direct-vent boiler results in an orphaned water heater still connected to an existing vent or chimney, that may now have inadequate draft to remove the water heater combustion emissions, the contractor shall inform the homeowner of necessary remediation steps (e.g., installing a chimney liner) to provide proper venting and code compliance.
If installation of a new direct-vent sealed-combustion boiler results in a vacated entry point in the chimney, the hole in the chimney wall shall be sealed.

BASC Guides

This guide can help you assess an existing Heating, Ventilation and Air Conditioning (HVAC) system for potential intervention such as repair, upgrade or expansion, or replacement.

Guide describing gas-fired boilers and hot water heat distribution systems used for home heating.

Guide describing oil-fired boilers and hot water heat distribution systems used for home heating.

Guide describing condensing boilers and hot water heat distribution systems used for home heating.

Tips to Sell Quality Installed Home Improvements

Home Improvement Expert (HIE) is a valuable tool for organizations committed to quality installed work. The following tips help optimize the value of this tool when selling home improvements:

  • Be the Expert: Take advantage of Building America Solution Center comprehensive guidance on ‘Existing Home’ retrofits.
  • Earn Trust: Inform homeowners how your work conforms to U.S. Department of Energy (DOE) world-class expert guidance and recommend homeowners visit the DOE website as evidence these are indeed official best practices.
  • Clarity with Contrast: Tell prospective homeowner clients to compare your expert recommended best practices with other contractors.
  • Ensure Equivalent Pricing: Tell prospective homeowner clients to insist other bids also include DOE checklists to ensure equivalent quality work.
  • Translate Value: Note your company uses DOE HIE Checklists based on world-class expert recommendations for home improvements on all your public-facing communication including websites, advertising, and signage.
  • Create Emotional Experiences: Provide visual evidence contrasting the difference between poor and high quality work such as infrared images for good and bad insulation and air sealing; pre- and post-energy bills following quality installed work; short and long warranties for standard and high-efficiency equipment; and charts showing amounts of contaminants in homes that can be reduced with effective fresh air systems.

Oil or Gas Boiler Replacement Background

Installing an electronic controller to a boiler

Systems for heating and cooling your home cost more money and use more energy than any other system in your home—typically over 50% of your utility bill. High-efficiency sealed-combustion direct-vent oil and gas boilers have efficiencies exceeding 90% and improve safety by drawing combustion air from outside instead of indoors and exhausting emissions through sealed flues. However, a quality installation is integral to a well-performing system. Nearly half of all heating and cooling systems in U.S. homes are not installed to the manufacturers’ instructions and perform below rated capacity and efficiency.