I have an older Leisure Bay SPA with ProShield controls and am planning on replacing all of the components with a new spa pack (controls/heater, pump, blower). I am trying to determine the proper spa pack to purchase for this rebuild. The question I have is where should the spa control/heater be in relation to the pump – before on the suction side of the pump or after on the pressure side of the pump. My spa control/heater is currently installed on the suction side of the pump (see flow below). However, it seems like the majority of spa controls/heater are located after the pump. Does it matter what side of the pump the spa controls/heater is installed?

Also, any reccomendations on a spa pack to replace my current one are welcome. Thanks in advance for the help!


My Spa:
Drain / Skimmer >flow> Control Pack / Heater >flow> Suction side of pump >flow> Discharge side of pump >flow> Return line to filter >flow> Jets

Common Recommendation:
Drain / Skimmer >flow> Suction side of pump >flow> Discharge side of pump >flow> Control Pack / Heater >flow> Return line to filter >flow> Jets

Of the equipment I am familiar with (last 5yrs) it doesnt matter which way round (suction/pressure side), and theoretically, it should make no difference anyway as long as there is sufficient flow and the system allows trapped air to escape above the heater.

Our new system by Spa Net Australia can have the heater mounted either side of the circ.

Always mount the heater horizontally where possible (unless instrctions say otherwise), with a slight incline in the direction of flow so that water flows upwards slightly as it travels thru the heater. This prevents air collecting inside the heater tube which can cause problems.

The most crucial thing is to get the flow direction thru the heater correct, otherwise the spa may overheat or not heat enough, depending on the design. This is because the heater normally has heat sensors before/after it in the heater tube.