Solar Pool Heating

Description
Pools and spas heated by the sun need to have an accurate controller for two reasons. First, it is important to maximize the utilization of the solar energy available by circulationg water through the collectors when heat can be picked-up and not circulating when heat could be lost through this circulation. The second reason for a controller is to allow the pool ownwer/operator to accurately adjust the maximum desired temperature. For these two reasons the Helio-Matic has been selected above any other competitors for the Olympic Games in Atlanta and elsewhere when the criteria is accuracy and reliability.

Choice of Models
JED Engineering offers two different Helio-Matic models to facilitate control of solar pool heating:

 

HM4000C
The HM4000C utilizes the existing pool's circulation pump for solar heat pick-up. The HM4000C has a front panel switch which provides for nocturnal pool cooling instead of heating. Cooling is used in conjuction with the pool's filtration pump being allowed to run during the early dawn, cooler hours. The HM4000C works in conjuction with the Flo-Verter 12VAC valve (or other manufacturer's 12VAC valve.) The valve allows circulation by the pool's filtration pump either through the solar collectors or not through the solar collectors. During nocturnal cooling the solar collectors serve as a source of a lower temperature than the pool water and thus reduce the pool's elecated temperature casused by excessively warm days. Fusing is accessed by removal of a barrier attached to the front panel. The HM4000C has the additional feature of being able to be used with either 12 or 24 volt valves.

 

HM5000C
The HM5000C is identical to the HM4000C except that in addition to operating either a 12 or 24 volt valve, the HM5000C will also operate a separate pump that is dedicated to solar circulation only. The pump can be sized up to 1HP with 120VAC and 2HP with 240VAC.


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A unique feature of the HM5000C is a built in time delay for pool sweep considerations. When the HM5000C calls for solar heat pick up, the valve will immediately activate. However, there is an approximate 8 minute delay before the pump turns on. This feature prevents pool sweep malfunction due to the introduction of air into its pumped line. This function can be disabled. When using a valve system only, the pool sweep pump may be wired to the HM5000C output (must be the same voltage as the pool filtration pump.) This method of pool sweep hook up will allow the pool sweep to operate only when the solar collection is taking place and the piping system will be purged of any air.

 

Flo-Verter
The Flo-Verter valve can be used with either of the Helio-Matic models. The Flo-Verter valce is a 12VAC, 2" valve. The Flo-Verter never needs lubrication, utilizes permanant magnet synchronous motors, has an extremely low CV factor due to the curved/directed flow channel inside the diverter, and may be mounted in any position except upside down.


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One port is identified "FLOW TO COLLECTOR." An adequate length of three wire color coded cable is permanantly attached to the Flo-Verter valve and these three wires connect to the color identified terminatls at the Helio-Matic controller. There is never a need to check flow direction as an error is impossible if the same colors are connected together. The Flo-Verter is a non-positive seal valve and the diverter has a small hole, which allows the collector to drain when the system is off. This draining prevents collector damage due to freeze ups.

 

Sensors
The standard sensors are one AS-2-10 aluminum sensor for collector simulation and one IS-1.0 sensor which is clamp inserted into a drilled hole in 1 1/2" or 2" pipe. If a glazed collector is used, specify the SAS-10 sensor instead of the AS-2-10. Other substitute sensors are the BP-25-10 and BP-50-10 which are brass threaded 1/4" and 1/2" MBT.

 

Freeze Protection
Freeze protection is accomplished in a valve controlled system by the collector draining back to the pool when the circulation pump is off. The air venting and vacuum relief valves allow air to enter the collectors at the highest point. On non-draining types of collectrs such as those mounted below pool level and on certain system designs where the collectors do not drain back to the pool, a different method of collector freeze protection must be provided. For these systems the FS-4 freeze sensors are available which, when wired with an HM5000 unit, will cause the pump to turn on at 42 degrees farenheit, thus preventing the collector from freezing. Helio-Matic and Flo-Verter valve are manufactured by Heliotrope Pool, and distributed by JED Engineering, Inc.