I have a 1969 Airstream Ambassador travel trailer with the original air-conditioner.  I like to upgrade things while keeping them as original as possible.  I decided to rebuild the air-conditioner (new compressor, new fan motor), but while I was at it, I figured I would turn it into a heat pump as well! A heat pump is just an air-conditioner that can change the path of the refrigerant.  In cool mode, the refrigerant goes from the compressor to the heat exchanger outside the cooled space (condenser), through the capillary tube (or thermal expansion valve, TXV), into the heat exchanger inside the cooled space (evaporator), and then back to the compressor.  In heat mode it goes from the compressor to the heat exchanger inside the heated space (condenser), through the capillary tube (or TXV), into the heat exchanger outside the heated space (evaporator), and then back to the compressor.  Remember, heat flows out of the evaporators and into  condensers. This unit uses a capillary tube to restrict refrigerant flow and generate the pressure needed to condense the refrigerant.  

Modern units use TXVs to regulate the pressure of system.  While they are more efficient, they generally only work when the refrigerant flows in one direction unless they are specifically designed for heat pumps.  A capillary tube is a long, thin tube that is a specific diameter and length to generate a specific pressure.  There are no mechanical parts in a capillary tube, therefore refrigerant can flow through it in both directions.  So in order to make this A/C a heat pump, I only needed to add a reversing valve and reroute the copper tubing. Here's what I did: -Remove unit from roof of trailer. -Get part numbers of compressor and fan motor to find compatible replacements, if needed.   -Measure copper tubing diameter so you can but a compatible reversing valve.  Reversing valves come in different sizes based on how big the unit they are designed for.  Try to find a valve that has the same size fittings as the copper tubing in the A/C unit.  If not, you'll have to get adapters to step up or down sizes.  

Remeber, refrigeration copper is "tubing" and is measured on the outside diameter and not "pipe" which is measured on the inside diameter. Step 1: Install the piecesShow All Items« PreviousNext »View All Steps DownloadGeothermal Heating and Cooling is often referred to as Geoexchange, Geothermal, or Ground Source Heating and Cooling. They all mean the exact same thing, so don’t get confused by these names being interchanged. We are NOT talking about geothermal power (involving power plants generating electricity). Geothermal heating & cooling is not to be confused with a geothermal power plant. A geothermal power plant generates electricity using the core of the earth – we are not referring to this, ever. We are talking about using the crust of the earth to heat and cool a home or building; there is no lava or electricity generation involved. Geothermal works because the ground beneath our feet is warmer then the outside air in the winter and cooler in the summer. Inserting a series of small pipes into the ground allows heat to be transferred to and from your home.

In this process heat is not created, it is transported therefore no fuel is burned. 1. Heat Pump - the inside unit known as the heat pump 2. Ground Loop - underground pipes which connect to the heat pumpwindow ac units vertical Winter Operation: The underground pipes, called a ground loop, circulate water which absorbs the heat from the earth and returns it to the indoor heat pump. self contained ac and heat unitThe heat pump extracts the heat from the liquid then distributes it throughout your home as warm air. air conditioner split system costWith the heat removed, the water is re-circulated to collect more heat from the ground. In this case the loop water is warmer when it comes into the home than when it goes back into the earth since the heat is being removed.

Summer Operation: The indoor heat pump takes the hot air from your home and removes the heat. This leaves behind cool air to be distributed through your vents as air-conditioning. The removed heat from the air is rejected into the earth through the ground loop. In this case the water is warmer leaving the home then when it returns since heat is rejected into it. This is not a new technology, this is not a science experiment, this not rocket science. In fact in many European nations geothermal heating and cooling is the standard. In Sweden and Switzerland more than 75% of new homes have geothermal. The EPA has acknowledged geothermal systems as the most energy efficient, environmentally clean, & cost-effective space conditioning systems available. This is a high level explanation of geothermal, for more specifics read about loop fields and system sizing. You should also watch the video below. There are many benefits of geothermal you should learn before you contact your local geothermal contractor.

Heat pumps draw heat energy from outdoor air using refrigerant to keep your home warm during the winter. In the summer, the cycle is reversed to expel heat from the home and cool the air. Unlike a standard furnace or air conditioner, heat pumps offer a high level of energy efficiency to keep utility costs low. An inverter, or variable-speed, heat pump maximizes efficiency and reduces energy lost during the refrigerant cycle. Inverter heat pumps reduce cycling to keep your family more comfortable and to eliminate cold drafts. By minimizing energy lost during cycling, they also improve your home's overall energy efficiency and reduce energy consumption. This not only helps keep your heating and cooling bills in check but also protects the environment from the effects of air pollution and greenhouse gas emissions. In some heat pumps, the inverter technology may also reduce operating noise and extend the life of the compressor and other system components. Manufacturers often use the terms "variable speed" or "multispeed" to refer to heat pumps with built-in inverter technology.

Consumers should be aware that these terms are also used to describe the heat pump blower. While variable-speed blowers offer advantages of their own, they are unrelated to variable-speed compressors. Some inverter heat pumps also cost more than standard models and may require additional maintenance because of a more complex operating system. Both ducted and ductless heat pumps may use inverter technology to improve energy efficiency. Ducted units work just like your air conditioner or furnace, transporting air to each room through a network of ducts. Ductless, or mini-split systems, include an outdoor compressor and indoor condenser connected by a series of tubes. The tubes carry refrigerant between the two units, eliminating the need for ducts. Because inverter technology increases a heat pump's energy efficiency rating, many inverter uses qualify for federal and state tax credits. Before you buy, make sure the unit you're considering qualifies for these incentive programs.