How Does Mini Heat Pump for Pool Work?

A heat pump is a device that uses a small amount of energy to move heat from one location to another. Heat pumps used for heating pools transfer heat from the outdoors into the water. Unlike gas heaters that require natural gas or propane, they use heat that is already available and just move it from one place to another, thereby using a cleaner heat via electricity, producing no carbon monoxide.

guangteng Product Page

Why Use a Heat Pump for Water Heating?

Reason #1: You Want to Use Your Pool Year-Round

Heat pumps are perfect for use in warmer climates! Heat pumps are most efficient when they’re heating outdoor air that’s above 50 degrees Fahrenheit. Anything below 50 and a heat pump does start to lose efficiency. In fact, heat pumps work more efficiently the warmer the air temperature gets.

Reason #2: Heat Pumps Yield Better Energy Savings

If you want to save on your energy bill, heat pumps provide great value.

Think of a gas heater as a muscle car and a heat pump as a bike. A gas heater will definitely heat your pool faster, but you’ll pay a price for it when the energy bill comes. On the other hand, a heat pump will provide an even and consistent heat once it reaches your ideal temperature, operating with much less effort. The U.S. Department of Energy confirms that if you run an average heat pump year-round at 85 degrees, you’ll experience up to $400 a year in energy savings.

Reason #3: Some Heat Pumps Can Cool Your Pool, Too!

If you’re in the market for a heater, you’re probably already invested in your pool, and making it an enjoyable experience. Why not go the extra mile?

A premium heat pump model won’t just heat your pool, but also keep the water cooler when the weather is too hot outside.

As the pool water circulates through the pool pump, it passes through a filter and the heat pump heater. The heat pump heater has a fan that draws in the outside air and directs it over the evaporator coil. Liquid refrigerant within the evaporator coil absorbs the heat from the outside air and becomes a gas. The warm gas in the coil then passes through the compressor. The compressor increases the heat, creating a very hot gas that then passes through the condenser. The condenser transfers the heat from the hot gas to the cooler pool water circulating through the heater. The heated water then returns to the pool. The hot gas, as it flows through the condenser coil, returns to liquid form and back to the evaporator, where the whole process begins again.

Higher efficiency heat pump pool heaters usually use scroll compressors versus the reciprocal compressors of standard units.

Heat pump pool heaters work efficiently as long as the outside temperature remains above the 45ºF–50ºF range. The cooler the outside air they draw in, the less efficient they are, resulting in higher energy bills. However, since most people use outdoor pools during warm and mild weather, this usually isn't an issue.

You should have a trained pool professional perform a proper sizing analysis for your specific pool to determine pool heater size.

Sizing a heat pump pool heater involves many factors. Basically, a heater is sized according to the surface area of the pool and the difference between the pool and the average air temperatures. Other factors also affect the heating load for outdoor pools, such as wind exposure, humidity levels, and cool night temperatures. Therefore, pools located in areas with higher average wind speeds at the pool surface, lower humidity, and cool nights will require a larger heater.

Heat pump pool heaters are rated by Btu output and horsepower (hp). Standard sizes include 3.5 hp/75,000 Btu, 5 hp/100,000 Btu, and 6 hp/125,000 Btu.

To calculate an approximate heater size for an outdoor swimming pool, follow these steps:

1. Determine your desired swimming pool temperature.
2. Determine the average temperature for the coldest month of pool use.
3. Subtract the average temperature for the coldest month from the desired pool temperature. This will give you the temperature rise needed.
4. Calculate the pool surface area in square feet.
5. Use the following formula to determine the Btu/hour output requirement of the heater:

Pool Area x Temperature Rise x 12

This formula is based on 1º to 1-1/4ºF temperature rise per hour and a 3-1/2 mile per hour average wind at the pool surface. For a 1-1/2ºF rise multiply by 1.5. For a 2ºF rise multiply by 2.0.

For an outdoor pool, use the following tables to help estimate your annual heat pump pool heater costs and savings compared to using an electric resistance or a gas pool heater.

For more Mini Heat Pump for Poolinformation, please contact us. We will provide professional answers.

Table 1 estimates annual heat pump pool heating costs by location, by water temperature, and with or without using a pool cover.

Table 1. Costs by Location of Heating Outdoor Pools with a Heat Pump*

LOCATION SEASON TEMPERATURE 78° 80° 82° Miami 1/1–12/31 $ $ $ w/ cover 1/1–12/31 $293 $409 $559 Phoenix 3/1–10/31 $927 $ $ w/ cover 3/1–10/31 $49 $116 $158 Dallas 4/1–10/31 $491 $ $ w/ cover 4/1–10/31 $123 $191 $279 Atlanta 4/1–10/31 $ $ $ w/ cover 4/1–10/31 $211 $279 $395 Los Angeles 5/1–10/31 $ $ $ w/ cover 5/1–10/31 $116 $211 $327 Kansas City 5/1–10/31 $974 $ $ w/ cover 5/1–10/31 $198 $279 $368 New York 5/1–9/30 $ $ $ w/ cover 5/1–9/30 $143 $204 $273 Chicago 5/1–9/30 $ $ $ w/ cover 5/1–9/30 $143 $204 $266 Denver 5/1–8/31 $ $ $ w/ cover 5/1–8/31 $95 $136 $204 Boston 5/1–8/31 $ $ $ w/ cover 5/1–8/31 $164 $225 $320 Minneapolis 6/1–9/30 $899 $ $ w/ cover 6/1–9/30 $136 $170 $259 San Fran 6/1–8/31 $ $ $ w/ cover 6/1–8/31 $129 $225 $327 Seattle 6/1–8/31 $ $ $ w/ cover 6/1–8/31 $204 $293 $382

*Figures based on a 1,000 square foot, outdoor pool heated with an air to water heat pump with an average COP of 5.0 at $./kwh.

Table 2 estimates the savings for every $ in annual pool heating costs using a heat pump pool heater compared to using an electric resistance or gas pool heater with an efficiency of 55% (baseline).

Table 2. Annual Savings Comparisons of
Gas and Electric Pool Heaters*

EFFICIENCY ANNUAL COST COST W/ 5.0 COP HEAT PUMP SAVINGS Gas Pool Heater 55% $ $700 $300 60% $915 $700 $215 65% $845 $700 $145 70% $785 $700 $85 75% $732 $700 $32 Electric Resistance 100% $ $200 $800

*Based on an electric resistance heated pool, which costs $1,000 per year at an electric cost of $./kwh, and using a gas pool heater with a 55% efficiency (baseline) at a cost of $1.09/therm. A seasonal average COP of 5.0 was used to determine heat pump savings.

Operation of a Pool Heat Pump

Heat Exchange:

The operation of a pool heat pump may seem complicated, but it is actually quite simple. In essence, it involves capturing heat from the air and transferring it to the pool water. By seeking to capture heat from the outside air, one is essentially aiming to capture the calories present in the air. The warmer the air, the more calories it contains.

Refrigerant:

To capture the calories from the air, the heat pump uses a refrigerant fluid. The refrigerant is a fluid that enables the implementation of a refrigeration cycle. The fluid has the ability to absorb heat from the air when its temperature and pressure are low, and release heat when its temperature and pressure increase.

Heating a Pool: The 4 Steps of Heat Pump Operation

1 – Evaporator or Air Exchanger: Its function is to exchange air. When the fluid passes through the exchanger, it is in a liquid state (low pressure and low temperature). The fan circulates air over the air exchanger, capturing calories. This leads to a rise in the fluid’s temperature, turning it into a gas. This step explains why the air blown by the heat pump feels cold; it is actually 10 to 12 °C cooler than the ambient air as it loses calories.

2 – Compressor: At this stage, the gaseous fluid enters the compressor. The compressor, as the name suggests, compresses the gaseous fluid to increase its pressure.

3 – Water Exchanger: The high-pressure gaseous fluid then enters the titanium exchanger. Its function is to transfer the calories collected by the fluid to the pool water. The water circulates around the titanium exchanger’s coil and absorbs the calories from the fluid. This heat exchange has the opposite effect on the fluid, causing it to lose calories, cool down, and return to a liquid state while decreasing in pressure.

4 – Expansion Valve: Finally, the liquid fluid enters the expansion valve, which lowers its pressure again to capture as many calories as possible when it returns to the air exchanger.

Cooling the Pool:

If necessary, a heat pump can also cool the pool water. To do this, the heat pump is equipped with a 4-way valve that reverses the flow of the fluid in the refrigeration cycle. The air exchanger then releases its calories to the air, causing the refrigerant’s temperature and pressure to drop. In the titanium exchanger, the refrigerant absorbs the calories from the water, leading to a decrease in its temperature.

Defrosting:

When the temperature drops, ice can form on the evaporator and block the airflow. To remedy this, the compressor increases the pressure and, consequently, the temperature of the refrigerant. The hot fluid then passes through the evaporator to melt the ice.

Want more information on High Temperature Heat Pump Water Heater? Feel free to contact us.

Factors Influencing Heat Pump Performance