This blog has been relocated
This blog has been relocated
In our blog post ‘About Geothermal Heating and Air’ in May we explained the three major components of a Geothermal System: The earth loop which warms water in heating mode and cools down in cooling mode, the air duct system in the house to blow warm or cool air into the house and the unit in between, the heat pump. Today we want to try and explain in layman terms, how such a heat pump works.
To start we need to remember, that heat flows naturally along the temperature gradient, from hot to cold. So a heat pump must overcome physics and transport heat from cold to hot.
Heat pumps accomplish this by using physics again: When a gas is liquified, lots of energy is stored in the then liquid and this energy is being released as thermal energy when the liquid is allowed to evaporate into the gaseous state. In heat pumps these gases/liquids are called refrigerants.
From here let’s quote a section of Wikipedia about mechanical heat pumps, paragraph Principle of Operation (modified/shortened for the purposes of this blog post)
Mechanical heat pumps exploit the physical properties of a volatile evaporating and condensing fluid known as a refrigerant. The heat pump does work on the refrigerant to make it hotter on the side to be warmed, than at the cold side where heat is absorbed.
The working fluid, in its gaseous state, is pressurized and circulated through the system by a compressor (4). On the discharge side of the compressor, the now hot and highly pressurized vapor is cooled in a heat exchanger, called a condenser (1), until it condenses into a high pressure, moderate temperature liquid. The condensed refrigerant then passes through a pressure-lowering device, the expansion valve (2). The low pressure liquid refrigerant then enters another heat exchanger, the evaporator (3), in which the fluid boils, evaporates and absorbs heat. The refrigerant then returns to the compressor and the cycle is repeated.
A simple stylized diagram of a heat pump’s vapor-compression refrigeration cycle: 1) condenser, 2) expansion valve, 3) evaporator, 4) compressor.
In such a system the temperature properties of the refrigerant are extremely important as the compressed refrigerant in the condenser must be hot enough to heat and it must be cold enough after expansion to again absorb heat.
For the purpose of a geothermal heat pump the above process is designed reversible to allow for:
Now we understand the principle of a heat pump, no miracle, just physics and a great design by the manufacturer to provide us the effectiveness we expect.
As temperatures rise so does the complaint that it’s not the heat, it’s the humidity. A variation of this holds true inside the home, and that’s why comfort during Carolina summers is about more than keeping your cool. Indoor humidity—the amount of water vapor in the air—affects not only how comfortable you feel but also impacts air quality which, in turn, can impact your health.
Not too much – Ideally, indoor air should measure between 30 and 50 percent relative humidity, according to the EPA, and should never exceed 60 percent. That’s because high humidity means excessive moisture, leading to mold and other microorganisms as well as structural damage. Signs of high humidity include mold growth in closets, on ceilings, and behind wallpaper; foggy or damp windows, musty odors and rotting wood. Health concerns include itching, sneezing and coughing as common allergens—think mold and dust mites—thrive in high humidity.
But not too little either – humidity reading should not be too little, either. Low humidity, generally an issue only in winter, presents its own set of problems. Signs of low humidity include static electricity, dry and/ or irritated skin, dry sinuses and increased incidences of flu.
Common cold. Quite often, high humidity is caused by over-sized air conditioners; a too-big system runs short cycles, lowering the temperature quickly without running long enough to pull moisture out of the air. Another common cause is improperly sealed duct work with leaks that decrease your system’s dehumidifying capacity.
Simple fix. Sometimes the solution is as simple as installing a dehumidifier (or humidifier during the winter). Portable units are available but, for increased e f f e c t i v e n e s s , consider a whole house dehumidifier. Such a device improves air quality AND reduces electric bills by allowing you to raise the thermostat a few degrees without sacrificing comfort.
More questions about humidity and comfort?
Contact our home comfort specialists for answers. Carolina Heating Service specializes in indoor weather solutions and not just heating and air conditioning.
Call at 864.232.5684. It’s about more than keeping your cool!
Today’s blog is looking at geothermal heating and air conditioning and we want to answer some of the questions about geothermal in general.
To start, let’s quote a couple of facts Scott, owner and president Carolina Heating Service, has presented in a recent meeting:
Even when we assume that these facts are greatly overstated we can conclude that using the energy already present is a smart and money saving move.
How do geothermal systems work? Let’s look at the components:
How about the money saving?
While the heat to and from the earth is a free product of our environment electric energy is typically used to operate the system: run the heat pump, blow the hot or cool air into the house and to pump the water through the ground loops for energy transfer. The experienced ratio of electric energy used to free geothermal energy gained can be as high as 1:4. Compared to traditional heating and air using electricity and fossil fuels we can theoretically estimate savings of up 80%, a pretty good deal.
We already learned from the geothermal facts in the introduction, that even the EPA estimates somewhat lower energy ratio. We can easily imagine that house insulation and windows to name just two influences, influence this ratio drastically. So the actual numbers including equipment needed, thermal conditions of the house and finally an estimate of saving can differ widely from application to application.
For more information visit www.carolinageoheating.com.
Ask your locale heating and air contractor for a detailed estimate of your specific application. Or Contact the Carolina Heating Geothermal Specialists.
This much for now. We will dive into the theory and the practical function of the heat pump itself at a later blog.
For this weeks blog post we decided to start a new series of posts, the “Equipment of the Month”. We will be introducing only the equipment we install most often and our customers have only the best experience with.
And since summer is heading our way we want to start our equipment blog with an air conditioning unit, the Trane XL20i.
This air conditioner is designed for highest efficiency and exists in variants from 24,000 BTUH to 60,000 BTUH what make it suitable for a wide variety of residential and commercial applications. Here some of the highlights of the XL20i series of air conditioners, taken right from the Trane brochure:
And our sales team and the repair department can only confirm: satisfied customers praise the general function and usability, the comfort and the lower operating cost compared to old systems the XL20i has replaced. and when properly maintained, no repair needs since the introduction of the XL20i series.
More about the Trane XL20I can be found in the brochure or on the Trane website.
Carolina Heating Service Inc.
1326 Piedmont Hwy.
Piedmont SC 29673
Phone: (800) 261-0359