I've been fighting 3 Rainbow 320 10-tab chlorinators all summer on 3 different pools . When the pumps shut off for the night, the water drains from the chlorinators. When the pumps turn on in the morning, none of the chlorinators refill with water.
Random information and thoughts:
- I have replaced the check valves in the bottom of the canisters on 2 of the 3 with no change in behavior
I have replaced the lid gasket on 1 of the 3 with no change in behavior
At my next weekly visit, either 9 or 10 of the tabs still remain
Tabs are dry after turning off the valve, removing the lid, and the pump has been running
On one of the Rainbows, I can hear an actual hiss of air either escaping from or entering the Rainbow when removing the lid (not sure which)
On each of the 3, turning the valve from 'Off' to say 4 or 5, with the lid off and the pumps running, has water gushing into the canister
As long as the canister is full of water (by letting it fill up with the lid off), it works fine until the pump shuts off
It is as though the Rainbows are suffering from some kind of vapor lock. My assumption is that the water is supposed to drain from the canisters when the system shuts off. The chlorinators even say on the side that when recharging them, turn the valve to 'Off' and shut off the pump for 1 minute to allow the water to drain from the canisters before removing the lid.
I can't think of any reason why these Rainbows will not fill back up with water when the pumps turn on in the morning. Any ideas? How does air enter the canisters in order for them to drain anyway? These 3 pools represent 75% of the pools I service that use these types of chlorinators. This leads me to believe it is something I might be doing wrong. The other pool that uses the Rainbow runs 24/7 and regularly uses up most of its tabs each week (it never has a chance to drain). Thanks!