- Category: HVAC
How Geothermal Works - Geothermal Process
The Science Behind the Magic - Outdoor air temperatures vary greatly throughout the year while temperatures underground stay fairly constant. The earth absorbs and stores approximately 47% of the sun's solar energy. As a result, the temperature of the earth four to six feet below grade is fairly moderate and stable.
The underground temperature in northern climates is approximately 10 degrees Celcius or 70 degree Fahrenheit year round. The geothermal system takes advantage of this stored energy by using it to provide the most energy efficient heating and cooling system available.
Rather than generating heat, a geothermal system transfers heat from one place to another. The heat exchanger, commonly referred to as a closed loop system, is buried in the ground and circulates a water solution through a series of pipes. This solution captures the stored solar warmth and delivers it back to the geothermal system located in the house. The geothermal unit then transfers the solar heat throughout the house using standard forced air ductwork or radiant floor heat to deliver comfortable indoor temperatures during the winter.
The same geothermal unit and heat exchanger will reverse this cycle during the cooling season to provide air conditioning. The system removes heat and humidity from the air, transfers and deposits that heat back into the earth through the same loop system.
Heating and Cooling Cycles
During the heating cycle, the fluid circulates through the loop extracting heat from the ground. The heat energy is transferred to the geothermal unit. The unit compresses the extracted heat to a high temperature and delivers it to your home through a normal duct system or radiant heat system.
For cooling, the process is simply reversed. Because the earth is much cooler than the air temperatures on a hot day, the geothermal system removes heat from the home and deposits it into the ground. The fluid is cooled by the ground temperatures and returned to the unit for cooling your home.
- Category: HVAC
The Basics Behind How Your Furnace Works
You have your thermostat set to 22°C. The thermostat will regulate the air temperature by engaging the furnace whenever the temperature drops below your specified amount.
When a modern furnace engages a few things happen:
1. First, the signal from the thermostat is received – Many programmable thermostats will make a “clicking” sound when the signal has been sent.
2. Fuel is then sent to the burners – At the heart of a gas furnace are burners, designed in such a way so as to maintain an even, controlled flame.
3. Once ignited, the furnaces internal sensors check to verify that all burners are lit – If a burner has not lit the entire mechanism will shut down and wait a predetermined period of time (varies based on each furnace) before attempting to reignite.
4. The burners heat a device called a heat exchanger – A heat exchanger more efficiently warms air (compared to the burners on their own).
5. A blower engages to circulate air through the heat exchanger – Once the heat exchanger has reached its operating temperature the blower motor is engaged, circulating air that has been sucked in through cold air returns. This air is forced over/through the heat exchanger and then sent throughout the home.
6. A network of ducts directs the air throughout the house.
Modern furnaces are far more efficient at this process compared to older, antiquated furnaces. They also utilize a series of fail safes and safety mechanisms designed to protect both your home and the furnace from failure. Learn more about your furnace from the experts at Action Furnace.
Note that the process for electric furnaces is nearly identical, though instead of burners an electric furnace uses resistance coils/tubing to create heat.
- Category: HVAC
How Radiant Heating Works
In a radiant floor heating system, warm water flows through flexible plastic tubing called PEX that is located underneath or within the floors. (PEX is an acronym for crosslinked polyethylene.) The PEX tubing carries the warm water into specific rooms or “zones” to effectively heat people and objects in every corner of the room.
In addition to the PEX tubing, the other main components in a radiant heating system include a heat source, pumps, manifolds and controls. The heat source in a hydronic radiant floor heating system is typically a boiler or a hot-water heater. However, other heat sources can be used, including highly energy-efficient sources such as geothermal and solar.
And because a radiant floor heating system is designed in zones, you have the luxury of changing temperatures for each room, depending on its use. This makes the system even more energy efficient because unoccupied or lower-use rooms (such as a guest bedroom or formal dining room) can be set to a lower temperature than rooms with greater use (like a kitchen, bathroom or basement).