Selecting Your Heater

Once you have determined the heating technology that best suits you, the next decision will be how to select the correct sized heater and how to differentiate differing quotes for installation.

The heat transfer capacity of the heater should then be your first point of comparison of heating systems. It will be the size of heater selected that determines the temperature, swimming season and length of time to heat the pool.

Each pool and home is unique. However, most of the heat loss from a pool is suffered through the surface. A pool loses heat whenever the surrounding air temperature is less than the pool water temperature. The rate of heat loss is quantifiable, and this rate is used to determine the amount of heat needed to keep a pool at a given temperature. The determination of the rate of heat loss for your pool based on several factors, including the size and shape of the pool, pool shading, geographic location, swimming season, desired pool temperature, wind exposure, blanket use, etc

Solar systems will be compared according to the total collector area, measured by m2 and expressed as a percentage of the pool surface area. Increased collector provides a direct proportional increase in heat transfer.

Gas heaters are rated by energy input, expressed as Megajoules (MJ) per hour. The higher the MJ rating, the higher the heat output. Gas heaters are also tested to Government standards to provide an output efficiency. This is the efficiency of the heater in transferring heat input (gas consumed) to water heating.

Heat pumps are also rated by heat output, in this case expressed in Kilowatts (KW). The manufacturer determines the KW output at a specific water/air temperature and relative humidity value. To accurately compare one unit to another, these test values must be the same. Look for the KW output and efficiency at a common rating value to ensure a valid comparison.

In NSW, a standard modelling software is applied by the pool industry. The Poolheat Model was developed by the University of NSW and this will examine the hourly heat loss characteristics of a pool, based on all the variables of design. The output of this program will give you good indicative information on comparative heating costs, energy input, etc.

New or Existing Pool Heating

Whether your pool is new or old presents no difficulty for the addition of pool heating. With new pools, your pool builder will most probably provide separate suction and return piping for the heating circuit. This allows the heater operation to be independent of the filtration cycle and ensures that the heater does not interfere with the pressures needed for in-floor cleaners, etc. With existing pools, the heater is readily connected to the return line, after the filter and upstream of any chemical treatment.

Pool Blankets

Pool blankets are one of the most cost effective elements of any heating system. Since 70% of all heat loss is evaporative and convective, the blanket provides a simple barrier and cut almost all of these losses when in use. The net result is significant savings in heating costs.

Installation

The design and installation of any heating system should only be undertaken by experienced people who know all of the considerations involved.