As required by New Jersey building codes, Oxford Energy has specified the right sized heating and cooling equipment for your home in accordance with the Air Conditioning Contractors of America (ACCA) Manual S based on building loads calculated in accordance with ACCA Manual J heating and cooling calculation methodologies. At the time your home was built, or your system was replaced, either the building codes did not require right sizing or there was a deficiency in enforcement. Right sizing the equipment is an essential step to maximizing energy savings and the comfort of the occupants.

Existing furnaces have up to 50% or more heating capacity than the home requires, therefore resulting in the furnace blasting a large amount of heat for a short period of time. This blast of heat causes the temperature in the room where the thermostat is located to reach the set temperature quickly causing the furnace to shut down long before enough heat reaches the farthest rooms in the house from the system. Houses with forced air heating systems are comfortable, or over heated, when the system is running, then cool down when the furnace shuts off. An oversized furnace results in this heating / cooling cycle to occur more frequently than a right sized system. A right sized furnace maximizes your comfort by extending the time the system runs to deliver and circulate the heated air in the home, providing more even temperatures throughout, even in the farthest rooms. The longer furnace run time does not increase natural gas usage, the amount of natural gas used is determined by the home’s heating load and the efficiency of the system.

An oversized air conditioner results in a decrease in the system’s ability to properly dehumidify, causing an uncomfortable cool humid feeling, homeowners often mistake this as their air conditioner being too small. In addition, new highly efficient air conditioners require the system to run longer than older inefficient systems to achieve a cold indoor coil necessary to remove moisture from the air. A right sized air conditioner at startup expends most of its effort toward dehumidification, as humidity levels decrease the system then cools very efficiently. An oversized unit is deficient at dehumidification and mostly just cools the air in the home.

Oxford Energy has reviewed all pertinent information regarding the obtainable details of your home, the heating and cooling load calculations, and the size of the equipment in your Scope of Work. Oxford Energy stands by the specified equipment as being the right sized systems for your home to maximize energy savings and your comfort.

There are several factors that can cause the room over the garage to be cold in winter or warm in summer. 

Wall Insulation – Some rooms over garages have “knee walls” (i.e., walls with open attic space behind), the insulation in a knee wall is often left exposed on the attic side, which degrades the effectiveness of the insulation. 

Floor Insulation – Houses in New Jersey prior to 2007 were built to comply with the 1995 CABO MEC Energy Code, which required insulation to be installed under rooms over a garage but with no requirement on the quality of its installation, the insulation was poorly installed down on the garage ceiling. 

Airflow – in houses with only one furnace in the basement, this room is the furthest from the furnace, resulting in longer duct runs and more bends than the ducts that serve the other rooms, thus reducing the amount of heating airflow that reaches this room.

Oversized Equipment –  In many old houses, the furnaces typically have 50% or more heating capacity that the home requires. The room where the thermostat is located reaches the set temperature causing the system to shut down long before enough heat reaches the furthest rooms from the furnace. Houses with forced air heating systems are comfortable when the system is running, then start to cool down when the system shuts off, oversized systems result in this heating / cooling cycle to happen more frequently than a proper sized system.

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