HVAC 101


SEER stands for Seasonal Energy Efficiency Ratio.It is the unit of  measurement for the cooling efficiency of air conditioners and heat pumps. The higher the seer rating, the more energy efficient the unit. All models must be above 13 Seer as of 2012.

Split System

A split system is what you think of when you envision a home air conditioning system: an air conditioning condenser outside and an air handler inside. It is the pairing of an outdoor unit (air conditioner/heat pump) and an indoor unit (furnace/air handler).

Air Handler

The inside portion of an air conditioning system. It contains the compressor, fan, refrigerant, and coils.

Heat Strip

The electric(not gas) heating option in a split system. It is inside the air handler.


BTU stands for British Thermal Unit. In our context, BTU represents the measure of heat generated when gas/oil is burned for heating.

Heat Pump

A heat pump is an air conditioner and a furnace in one convenient unit. A heat pump uses electricity, not gas, to keep your home warm in the winter and cool in the summer.


The evaporator copper tubing inside an air handler.

Package Unit

A package unit is both a heating system and cooling system contained in one outdoor unit. Only a thermostat will be inside.


AFUE stands for Annual Fuel Utilization Efficiency. This is the gas furnace’s equivalent to air conditioning’s SEER. It is a rating of a gas furnace’s efficiency in converting gas/oil into heat. A rating of 78 means that 78 percent of the gas/oil is used to provide heat.

Heat Exchanger

 The heat exchanger transfers heat to the surrounding air, which is then pumped throughout your home.


“Fins” are aluminum heat dissipators outside. You will remember these as the things that you push in as a child that look like the outside of a radiator.


A condensor is the outdoor “air conditioner”.

Replacing Existing Equipment

As a rule of thumb, it pays to replace your existing home comfort system when the cost of repairs reaches 30% of the price of a new purchase – or when utility bills have increased by 50%. Learn how replacing your system can actually pay you back.

Energy Efficient Savings

When you understand what different energy ratings mean, you’re better able to choose a heating and cooling system that can save you money and energy. See how the efficiency of today’s ENERGY STAR qualified central air conditioners, heat pumps and furnaces can reduce your utility bills.

Improving Indoor Air Quality

Did you know that indoor air can be from five to 100 times more polluted than the air outside? Learn the difference between humidifiers, dehumidifiers, ventilation systems, UV lights and air filter technologies and how they can dramatically improve your indoor air quality.

Selecting a Dealer

You want to feel confident that you’re getting the home comfort system that best meets your needs. Our York Dealers are specially trained to make sure your system is installed and serviced right.

Installing a New HVAC System

In new homes or remodels, a central home comfort system is the best solution. Why? A central system makes your entire home more comfortable, with greater efficiency and better indoor air quality.


Areas Of Expertise

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Residential Service

We specialize in installing new Air Conditioning systems in your home as well as servicing your older HVAC system. At Jolly, we take pride in the quality of our residential products and services.


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Light Commercial

Light commercial installations and repairs are a major part of our business. Schedule an appointment today!



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System Replacement

Air conditioners and heating systems become very inefficient as they age and their lifespan shortens with each passing summer. When it is time to replace your unit, choose a high-efficiency 17-seer unit that will save you thousands over the life of the unit.



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New Construction

Let Jolly engineer your new construction HVAC system to spec. We account for square footage, radiant heat/light, btu’s of heat generated, among many other variables.

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Gas Logs

We carry the most popular brands of gas logs in the industry including Real Fyre and Ventless varieties. Visit our gas log showroom and let Johanna walk you through the different options.



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Tankless Water Heaters

Highly efficient tankless water heaters only heat water when you want hot water. It heats the water immediately and never runs out. Tankless varieties conserve an astounding amount of power/gas saving you thousands over the life of the heater.