Help? PH machine

[Busterffc]

PH machine. Make: Injecta. Model: Elite ph JE00PHWA0000. Water entering through the ph machine and then out into the ph minus bottle and not the other way / direction. Causes the ph- to run out of the bottle.

[waterbear]

This is a peristaltic pump used to inject acid into the pool to lower pH when it rises and is controlled by a pH probe in the pool. If this is a NEW INSTALLATION,it sounds like it was installed improperly and  the input and output lines are reversed causing water from the pool to run into the acid container instead of the acid being injected into the pool. IF THE UNIT WAS WORKING PROPERLY AND THIS PROBLEM RECENTLY OCCURRED then the system is malfunctioning and needs servicing by a qualified professional.

[RDspaguy]

The injector connection must face in the right direction in every one I've seen, and should be the LAST thing in the pipe before returning to the pool. Also, a check valve is recommended, which is often built in to the injector.

Rollers can become worn and tubing stretched such that injection pressure is reduced below water pressure, in which case backflow can occur (with a faulty or non-existent check valve) with the pump on or off. The pump itself should prevent backflow at normal pressures.

 

[waterbear]

Thanks @RDspaguy! I still have nightmares about malfunctioning acid pumps from the days I did commercial pool maintenance at a resort.