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How to Troubleshoot Swimming Pool Chlorinators

Pool chlorinators eliminate the daily chore of manually adding and measuring chlorine into your swimming pool. Composed of a canister installed right into the pool water return line after the filter, or in a bypass loop which diverts a little flow of pressurized water from the pump round the filter and back into the return, a chlorinator meters the flow of water above chlorine tablets or sticks that gently dissolve. Normally, the pump contains approximately 9 lbs of chlorine, sufficient to chlorinate a residential pool for about two weeks before refilling is required. With few moving parts and only a single manual adjustment, most troubles with pool chlorinators are limited to water flow issues.

Installation Errors

Dissolving the chlorine pills relies on water flowing in the right direction through the canister. A bypass chlorinator requires water by a “T” fitting immediately following the pump and carries it through a hose into an injection fitting from the chlorine canister. Chlorinated water leaves the canister in a hose which connects to the main return line after the filter. If the chlorinator was accidentally installed with these hoses reversed, then the injection process which dissolves the chlorine won’t function. Arrows on the side of the majority of chlorinators indicate the appropriate direction of water flow during the hoses.

Obstructed Water Flow

The injection fitting in which the inlet line connects into the canister contains very little water jets which will clog with debris, preventing sufficient water flow to dissolve the chlorine. Inserting the bent end of a paper clip into the flames to clear the blockage may restore water flow. An accumulation of calcium and other hard water deposits inside the pump can limit circulation in and out of the canister and bring about slow-dissolving pills.

Air Locks

Air which has entered the system elsewhere, typically through a leaky O-ring from the pump, may be trapped in the chlorinator pump and also cause an air lock. This may become evident by unscrewing the canister lid with the pool pump turned off. A very low water level in the canister signals the existence of air. Restarting the pump with the lid removed and permitting the canister to fill with water and purge the atmosphere may restore circulation through the system. After the canister fills with water, the lid ought to be reinstalled.

Improper Adjustment

The flow of water into the canister is controlled by a dial on the top or side of the chlorinator. Turning up the water flow dissolves the pills quicker, raising the concentration of chlorine from the pool. If the chlorine dissolves too gradually to adequately chlorinate the pool, turning the adjustment dial to a higher water flow may alleviate the issue.

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