Figure 8-4. - Ion-exchange unit for water softening.

Every 6 months, each individual valve should be inspected and tested for leaks and repacked if necessary.

Where multiport valves are used, they should be serviced and lubricated under the manufacturer's instructions. Lubricate this type of valve with grease as follows:

1. Add grease by a pressure gun to each grease fitting while the valve is set in "service" or "wash" position.

2. Turn valve one-half turn and add more grease.

3. Give valve several full turns to spread the lubricant.

This lubrication does not require that the softener be removed from service, but when the water flow is stopped, no grease will get into the water.

Quarterly, flush ion-exchange beds with chlori- nated water containing at least 2 ppm of chlorine. Do not use water with a hardness greater than 170 ppm, and be certain that the pH of the water is about neutral. Also, follow these directions.

1. Check the bed surface for dirt, fines, organic growths, and smoothness. Scrape excess foreign matter off and replace with new resin. When the surface is uneven, the gravel bed underneath is not distributing the wash water evenly. The remedy consists of removing the resin and gravel and replacing both in proper fashion.

2. Check the height of the ion-exchange bed surface; remove or add ion-exchange resin to maintain proper elevation. (A low elevation will allow excess fines and foreign matter to accumulate on the surface of the bed; a high elevation allows resin to be washed out during backwashing.) Extra ion-exchange resin may be 8-6