Manual 04 - Section 08







Solar Pool Heating Installation Manual
SECTION 8: Solar Pump, Pipework And Control Devices

8.1 GENERAL REQUIREMENTS

The pump and control devices should be installed as close as possible to the existing filtration equipment and wherever possible use the preferred connection configuration shown below.










Important Details

Note: To modify this Check Valve drill a 3 mm hole in the flap. This allows controlled drain back of the Collector Array without damage to the Solar Pump.

Note: This Check Valve is used to prevent recirculation through the Solar Pump.

8.2 PUMP SIZING

Two standard sizes of Solar Pump are available

Note: A separate Solar Pump should always be used to ensure that the filtration unit is not overloaded and damaged.

The following table will guide in the selection of the Solar Pump


 Roof Height     or  Total pipe length  or     Collector area       Pump

  Up to 5 m            Up to 40 m             Between  0 and 35 m2        500 watts (min)
  Up to 8 m            Up to 50 m             Between 10 and 45 m2        750 watts

If any of the conditions are greater than those in the last row of the above table a Solar Pump size larger than 750W may be required. The PVC pipe may also need to be increased in diameter from the normal 40mm.

8.3 RECOMMENDED PUMPS

General Requirements

Examples of Acceptable Pumps

     ONGA POOL PUMPS -   Model 464 - 550 watt
                         Series  600 - 750 watt and above

     DAVEY POOL PUMPS -  Model XB 90   - 600 watt
                         Model XB 130 - 750 watt

8.4 PUMP CONTROLLER

To obtain the optimum efficiency from the Solahart Solar Pool Heating system it is recommended that an Solahart Automatic Pool Controller be fitted to all systems.

          The Recommended Controller is 
 Solahart "Solar Heating Control" Model SC100D

The Solahart Automatic Pool Controller is plugged into a 10 amp power outlet which may also be time clock controlled to operate the pool filtration unit. Both the filtration unit and the Solar Pump should be plugged into the marked sockets within the Solahart Automatic Pool Controller . This ensures that the filtration unit and the Solar Pump are switched ON and OFF in the correct sequence thereby preventing damage to either system.

The Solahart Automatic Pool Controller uses two sensors to determine whether the Solar Pump should be operating. One sensor measures the temperature at the Collector Array while the other measures the pool water temperature.

The Collector Array Sensor (long lead) should be inserted into a 150 mm section of HYDROMAX Absorber Strip and fixed with Black Silicon Sealant to the roof in a convenient location between the Absorber Strips. The Pool Sensor (short lead) should be fitted into the suction line of the Filter Pump by drilling a 12.7 mm (1/2") hole and inserting the grommet and socket supplied with the Solahart Automatic Pool Controller. The leads from both sensors are to be connected to the marked terminal strip within the Solahart Automatic Pool Controller.

Although the filtration unit connection is within the Solahart Automatic Pool Controller enclosure it is not switched by the Solahart Automatic Pool Controller, it is controlled directly by a separate remote time clock or manual switch.

(a) Solahart Automatic Pool Controller Operating Instructions

Under normal circumstances the Solahart Automatic Pool Controller mode switch located under the Solahart Automatic Pool Controller should be in the automatic (centre) position. The desired pool water temperature is set by holding down the "Press To Set Temperature" button on the Solahart Automatic Pool Controller face and rotating the black knob located under the Solahart Automatic Pool Controller until the desired temperature is indicated on the digital display on the Solahart Automatic Pool Controller face.

The Solar Pump will only switch ON when the following conditions are met:

       The remote control time clock (or manual switch) is in the ON condition
                                and
       Pool temperature is less than the set temperature
                                and
       The Collector Array temperature is higher than the pool temperature

(b) Other Functions

8.5 CONNECTING THE SOLAR PUMP TO THE COLLECTOR ARRAY

The 40 mm supply and return lines should now be run from the Solar Pump to the roof mounted Collector Array. Wherever possible these pipes should be arranged such that there is a continuous fall from the Collector Array to the filtration unit. This aids with the drain back operation thereby ensuring there is no water left in the Collector Array when the system is switched off.

All pipes should be secured at regular intervals, Saddles should be sized so that the pipes can move freely to accommodate thermal expansion.

The method of connection to the Collector Array was described previously.

The first Saddle fixing of the supply and return lines should not be closer than one metre to the array. This will ensure that expansion in the Collector Array will not damage the connections.