Either you have an above or underground swimming pool and would like to extend the swimming season for days or weeks, consider checking this buyer’s guide for swimming pool heat pumps and get informed about the advantages, benefits, troubleshooting, maintenance, top rated models and comparisons.
In this article:
Pool heat pump works in a similar way as the conventional type. It uses electricity and hot surrounding air (heated by the sun) for heating water - fan moves the heated air over an evaporator coil where the heat is transferred to the refrigerant.
The compressor and condenser then consolidate the heat. Water from your pool passes through a filter into coils near the condenser and picks up the heat before returning to your now nice warm pool.
Because of how they work and as large amount of energy is needed, swimming pool heat pumps are typically best used in moderate to warmer climates; due to the abundance of sun exposure and optimal pool water temperature throughout the season.
There are different types of heaters for heating the pool. The heaters can be powered by gas or electricity, or they can run on solar power. While all of them have the capability of being energy efficient, none of them do dual duty like a heat pump swimming pool heater can.
Solar powered units are certainly capable of transferring the sun’s energy into heat for your pool water, but the solar panels have to be very large for big pools, thus making them less than ideal for many homeowners. That’s why a swimming pool heat pump makes sense on several levels – it is energy efficient, it has low operating costs, it is reliable and durable, and it can have a small footprint.
The main advantage of the pool heat pumps over other types is that it offers an economical way of heating. They are very efficient and have very low operating costs. They don’t have to have a lot of work done to keep them up and running, and can often run for ten years or more worry-free or nearly twice the life expectancy of the gas heater. These heat pumps do not use fossil fuels and so they don’t put any pollution out into the atmosphere.
On the other side gas and electric are more expensive to operate while solar cannot provide enough BTU or extend your swimming season, plus there are installation restrictions.
If you already have an existing gas heater, by adding a heat pump you can reduce the pool heating costs by 50% and reduce even more the pollution.
There are only few drawbacks – they heat the water more slowly than an electric or gas model, and they cost a lot more upfront, more than $3,000, depending on the size and brand.
Also, the efficiency significantly drops with the decreasing temperature of the ambient air as the electrical demand is increasing.
A swimming pool heat pump is more expensive up front than a standard pool heater, but since they are much cheaper to operate in the long run, they can end up paying for themselves over time. These types of HVAC units can easily operate for ten years or longer.
They use either a scroll compressor that provides continuous compression, for varying temperatures, maximum efficiency and quiet operation, or a reciprocating one that utilize pistons for refrigerant compression which has more moving parts, but it does cost less up front.
A high quality material for the heat exchangers is very important due to the effectiveness of heat transfer and durability. For example, copper heat exchangers are becoming replaced by the aluminum or titanium as they are more resistant to mechanical and thermal stress and different water conditions.
An oversized pool heat pump is better than undersized. It costs more money, but at least you know that you will have a perfect water temperature. Undersized units cost less, but in the end it will run constantly, it won’t provide the comfort you need, it will consume more energy and will last shorter.
Sizing a swimming pool heat pump should not be a problem for an experienced contractor; it includes some calculations and some guess-work, but it depends on the following variables:
One of the calculations we have found online takes into account the above factors and give you the amount of heat in BTU per hour to maintain desired temperature:
Length x Width (pool area) x (Water temperature – Air temperature) x 12.
Or you can simply use this heat pump calculator from peintair.com.
Swimming pool heat pumps have another measure of efficiency called COP, or coefficient of performance. It is calculated as the ratio between the energy output and energy input. With the higher COP, unit is more efficient and the costs are lower. Also lower the COP, initial cost of the heat pump is lower while the operating costs are getting higher.
Another explanation of the COP - for each unit of electricity your heat pump’s compressor requires in order to operate, you should see an increase in the amount of units of heat that it can produce to heat your pool with.
For instance, a COP of 5 will give you 5 units of heat for one unit of electricity, or for 1 kW of energy used operating a heat pump, and with the COP of 5, 5 kW of energy will be produced. The COP and BTU output are important factors when selecting the right swimming pool heat pump.
The cost of the heat pump is probably one of the most important factors when buying a pool heat pump. But, initial price is not all that counts; there are also installation cost, operation cost, repair and maintenance cost. As mentioned before, the unit can easily cost you over $3,000.
You need to look at the few factors when selecting your swimming pool heat pump. The most important factors are the efficiency rating of the unit, the size of your house and the size of the pool, and how much you plan to use the pool. An HVAC or pool heating expert can help you determine the proper capacity heat pump for your unique situation. The contractor will also factor in the environment where you live, as factors like temperature variations, humidity, and high winds will affect your heat pump’s operation.
Note: You should also consider getting a cover for your pool, as this can save you as much as 90% on energy to heat it.
Swimming pool heat pumps can be purchased from the authorized dealers (recommended by manufacturers), online stores, and retail stores such as big chain stores: Lowe’s, Home Depot…
Look at the warranty conditions before buying a heat pump because it can save you significant amount of money due to unplanned repair costs. The warranty duration for the main components such as the heat exchangers and compressors is important factor when selecting the model and the most offered ones are five and ten years, while some companies such as AquaCal offer lifetime warranty.
Check out the review of the best heat pumps for swimming pools.
As it can be seen from the above buying guide tips, selecting the right swimming pool heat pump can be hard as there are many factors to take into account. Recommendation is to contact the authorized HVAC dealer or contractor for sizing, but sizing can also be done by the homeowner with the help of this guide, some calculations and available online tools. The heat pumps vary by size and capacity, and since the one you choose has to heat the water in your pool, it requires a little different rating than a standard heat pump would.