SWIMMING POOL & SPA
TOLL FREE (888) 297-3826
HOW A HEAT PUMP WORKS
The Aquatherm heat pump utilizes proven refrigerant technology to capture the heat in the outside air and transfer it to the pool water. Refrigerant is used because of its ability to absorb and transfer heat energy. The fan circulates air through the evaporator coil that acts as a heat collector. The liquid refrigerant in the air coil absorbs the available heat in the ambient air, transforming it into a gas.
The refrigerant gas is then pumped into the compressor. When this warmed gas is compressed, it intensifies or concentrates the heat, like a magnifying glass in the sun. The intensely hot gas is then pumped into the heat exchanger condenser, where the actual heat transfer takes place. As the pool water passes through the heat exchanger, the hot gas gives up its heat to the cooler pool water.
The refrigerant returns to a liquid state and is pumped through the expansion valve then into the evaporator air coil to start the process all over again. The result: a warm pool!
FREQUENTLY ASKED QUESTIONS
Why is a heat pump best for me?
For most people in Florida an Aquatherm swimming pool heat pump is the best choice for heating their pool, however not always. We sell thousands of solar systems a year to people who want no operating cost and don't object to the appearance of the solar collectors on the roof. Heat pumps are more than 5 times as efficient as a gas heater however they generate heat slower. You can't usually turn on a heat pump tonight and go swimming in the morning.
How long does it take to heat my pool?
Rule of thumb is that you will gain around 1/2 a degree an hour with a properly sized unit under normal conditions in Florida. This is an average net gain after you factor in your heat loss of the pool during the hour. Weather conditions will greatly affect the temperature of your pool. A 5 MPH wind can double your heat loss. Heat output and efficiency of the unit increases as temperature and humidity rise. An average 500 gallon spa will gain around 10 degrees an hour under normal conditions.
Should I use a pool blanket?
There is little doubt a pool blanket will cut your heat loss by 75% or more. By cutting your heat loss your heat pump has to run less and cost less to operate. On our website we will do an audit for you showing operating cost with and without a cover. There is an alternative to the plastic pool blanket. It is called "liquid pool blanket." It puts a molecular film over the surface which is invisable to the eye. It is not as good as a plastic pool blanket however it can cut your heat loss by 30 percent or more.
I've heard pool chemicals can damage a swimming pool heat pump. Is this true?
Yes, excessive chemicals and extremes in PH can affect some heat pumps, however nearly all heat pumps manufactured today have a titanium heat exchanger. Titanium is virtually bullet proof against pool water chemicals and we offer a 15 year warranty on those units. Bulletproof comes at a cost and the titanium units are substantially more expensive than the old cupronickel units. We have used cupronickel heat exchangers for over 10 years and have had little problem with them as long as they are installed properly and the pool water chemistry is kept in balance. Unfortunately some pool owners don't keep their pools in balance and that can cause a cupronickel heat exchanger to fail. When a cupronickel heat exchanger is breached it destroys the compressor as well and when pool water mixes with the freon gas, the entire unit is compromised.
Is it true a pool heat pump will only work down to 45 degrees Farenheit?
For the most part yes. The heat pump absorbs heat from the air and at around 45 degrees Farenheit the discharge air from the heater is around freezing. Condensation, created by this heat transfer runs off the evaporator coil and if the coil is below freezing ice will form. If the coil is frozen there is no heat transfer and damage can be done to the compressor, so the unit automatically goes into a defrost mode around 45 degrees. Keep in mind if it is 45 degrees outside very few people are inclined to go swimming. We used to build a swimming pool heat pump with a feature called "hot gas defrost." In the event the air coil would freeze up we would divert the hot gas, intended to heat pool water, back through the air coil to melt the ice. Considering the heat loss of the pool under those conditions and then only having the unit actually heating the pool water half the time adds up to wasting money. Proper sizing of the unit to do the job during the day eliminates the need for this feature.
What about the "new" alternative refrigerants I've heard about?
About 5 years from now refrigerant and heating manufacturers are going to have to stop using R22 Freon. Any unit produced prior to that will be able to be serviced as long as it is still in service. The reason the regulations don't go into effect for 10 years are in part due to there are a lot of bugs to be worked out. The alternate refrigerants operate at much higher pressures that R22 Freon. This creates additional stress on the entire unit. For instance none of the Scroll compressor from Copeland Corporation we use is approved for 410A refrigerant. We cannot predict how these increased pressures will affect our units over the long run especially in at high ambient temperatures and very warm pool/spa temperatures.