Heat Pumps

HEAT PUMP

A heat pump is an air conditioner that contains a valve that lets it switch between air conditioner and heater. When the valve is switched one way, the heat pump acts like an air conditioner, the other way it reverses the flow of Freon and acts like a heater.

The first thing that we must keep in the back of our mind while thinking air conditioner, heat pump and Freon would be to remember  that Freon can and does pick up heat all the way down to 360 degrees below zero.

The hotter the weather the more heat that Freon can pick up from air and the closer the temperature gets to 360 degrees below zero the less heat that it can pick up.

However, Freon can still pick up some heat at 359 degrees below zero.

I know, I sound like my high school science teacher but, by remembering this can help in understanding why we can save money with alternative energy.

For one thing a geothermal heat pump works just like the ones that have been around for years except because the ground water that it is working with started out at around 55 degrees not outside temperature the compressor stays on a lot less therefore less expensive to run.

The heat pumps in use now run on 220 volts however, if we use wind and solar power to run the compressor, fan and relay the electric company will be used only as a backup system.

Heat pumps can be extremely efficient in their use of energy. But one problem with most heat pumps in colder weather is that the coils on the outside air unit collect ice. The heat pump has to melt this ice periodically, so it switches itself back to air conditioner an electric coil heater comes on to heat up the coils. To avoid pumping cold air into the house in air conditioner mode, the heat pump can light up burners or electric strip heaters to heat the cold air that the air conditioner is pumping out. Once the ice is melted, the heat pump switches back to heating mode and turns off the burners.

Please check out these links below to help learn more about alternative energy.

A GEOTHERMAL HEAT PUMP WORK?

The heat exchanging tubes are in the ground, instead of in the air. In a geothermal system, water-filled tubes buried in the ground pick up the ground's heat

about 50° to 55° year round-and circulate that water to the heat pump.

You have to use a compressible gas system, Air conditioner, when you compress the Freon from a large volume to a small volume, you also compress the larger volume's heat, so by definition, there's a lot more heat per unit in the smaller volume, the surface of what's holding the compressed gas gets hot, too.

Now, if you blow air across that hot surface, you can heat your house.

When you blow air across the hot surface, you take the heat out of the compressed gas (cooling it), and the gas turns into a liquid. In order to turn it back into a gas, you have to warm it up and take the pressure off (give it a place to expand into). At this point in the cycle the fluid is now just about freezing temperature (32°), so the 50° water from the ground has plenty of heat to warm it up unlike the outside air in colder weather.

When you want to cool your house, the system runs in reverse: heat from the house expands the liquid into a gas and the warmed water in the ground loops stores its heat in the earth from warm water temperature to the 50 to 55 ground temperature.

Ground source (geothermal) heat pumps have several advantages over fuel-burning furnaces. They're environmentally friendly and efficient. Since the energy to heat your house comes from the sun and the earth's core, all you pay for is the electricity to run the compressor, the blower and the water pump. It's common to get 3 to 5 times the energy out of a heat pump than what you put into it.

Geothermal systems help heat your hot water. Compressors are not 100% efficient and produce a little "waste" heat (called "superheat", since the compressor's job in the heat pump is to make gas hot). Today's geothermal systems have a water-filled jacket, called a "desuperheater" which takes that extra heat and pumps it into your water heater. Every time the compressor runs to either heat or cool your house you're getting "free" hot water.

Geothermal systems are versatile and quiet. It's really easy to have forced-air heating and cooling, or radiant in-floor heat, say, in your basement or garage.