My rodi unit explodes under pressure

[Shawcabelguy]

Whenever my rodi is left on and the float valve closes in my bucket the Di resin cartridge lid explodes off and floods the place lucky I caught it soon but any ideas on how to fix this or how to like lower my income pressure down to like 35psi

 

[Ranjib]

You know how long it takes to fill your bucket. Just set a timer in phone and go shut it off right before it fills up. You can definitely glue the canister or use a solenoid to shut off the inbound water based on time of float switch state

 

[Saltyreef]

Use a real RODI system.

Standard 10" housings dont have this problem.

With 35psi you wont be pushing much of anything through your RO membrane anyways...

 

[KStatefan]

Replace the di with a standard 10" canister, add a auto shutoff valve.

 

[Gtinnel]

If you have a float valve you need an auto shut off valve as well, to stop flow from going into the membrane section and down the waste drain. The filter won't function properly if you drop your feed pressure to 35psi. The auto shut off valve I don't believe will change the pressure on th di canister though so I don't think it'll fix your problem. There is normally not all that much pressure on the output side of the membrane.

 

[KStatefan]

When you shut off the flow of water coming out of the DI the pressure will equalize with the incoming. Under normal operating conditions there is not much pressure past the membrane. The greater the pressure difference across the membrane the more efficient the membrane will run.

 

[Gtinnel]

When you shut off the flow of water coming out of the DI the pressure will equalize with the incoming. Under normal operating conditions there is not much pressure past the membrane. The greater the pressure difference across the membrane the more efficient the membrane will run.

So if the clean water outlet is completely closed (in this case on purpose by a float valve), then if there is no Auto shutoff valve to stop water from entering the membrane will the pressure equalize completely over the membrane? If so then that would explain the high pressure on the di.

 

[Saltyreef]

You guys rock.
@KStatefan & @Gtinnel

 

[Shawcabelguy]

Where would I get an auto shutoff valve

 

[KStatefan]

Where would I get an auto shutoff valve

BRS, @Buckeye Hydro , air water and ice, premium aquatics, saltwateraquarium.com, amazon

 

[Gtinnel]

Here is a link to one on BRS. But like @KStatefan said you can get them about anywhere.

1/4" Auto Shut Off Valve

Installation Instructions 1/4" Automatic shut off valves are used with float valves or pressurized tanks to shut off an RO system. It utilizes the back pressure created by the float valve or pressurized tank to shut off the water supply to the membrane. Without an automatic shut off valve...

www.bulkreefsupply.com

The auto shutoff valve blocks flow from going into the membrane when the flow after the di stops.

When you hook it up make sure to look for setup instructions. The tubes have to go in a certain way.

 

[anthonygf]

If you have a float valve you need an auto shut off valve as well, to stop flow from going into the membrane section and down the waste drain. The filter won't function properly if you drop your feed pressure to 35psi. The auto shut off valve I don't believe will change the pressure on th di canister though so I don't think it'll fix your problem. There is normally not all that much pressure on the output side of the membrane.

I have the pressurized water containment tanks and when it reaches 30psi is when the auto shutoff valve stops the flow, it will go higher without the valve.

 

[anthonygf]

If you have a float valve you need an auto shut off valve as well, to stop flow from going into the membrane section and down the waste drain. The filter won't function properly if you drop your feed pressure to 35psi. The auto shut off valve I don't believe will change the pressure on th di canister though so I don't think it'll fix your problem. There is normally not all that much pressure on the output side of the membrane.

Ihave the pressurized water containment tanks and when it reaches 30psi is when the auto shutoff valve stops the flow, it will go higher without the valve. If the incoming pressure is 70psi then the DI section will climb to 70psi to equalize pressure WITHOUT the shut off valve or if the water is not turned off manually.

 

[anthonygf]

Also get yourself several pressure gauges and place one at the INPUT to RO membrane and one at DI side or OUTPUT of RO. Before you install the auto shut off see what your pressure climbs to when the filter explodes. Do not hurt yourself.

 

[Gtinnel]

Ihave the pressurized water containment tanks and when it reaches 30psi is when the auto shutoff valve stops the flow, it will go higher without the valve. If the incoming pressure is 70psi then the DI section will climb to 70psi to equalize pressure WITHOUT the shut off valve or if the water is not turned off manually.

When I first though that the auto shut off valve wouldn't help I never though about the pressure equalizing across the membrane when there is no flow. With a proper setup the pressure on the di should never get very high, unless it does with a tank. I'm not very familiar with using the pressurized tank.

 

[anthonygf]

When I first though that the auto shut off valve wouldn't help I never though about the pressure equalizing across the membrane when there is no flow. With a proper setup the pressure on the di should never get very high, unless it does with a tank. I'm not very familiar with using the pressurized tank.

With or without the tank, if you do not turn off the water going to the RO the pressure will still increase to what the input pressure is. The tanks I have are for the RO systems designed for drinking water, the diaphragm air pressure is about 5-6psi. I have two 4 gallon and one 10 gallon all under 30psi water pressure. I have it setup this way because I also make drinking water with the DI water going through an alkaline filter for my drinking water, so when I need to fill up my counter top containers I have 10 gallons of water in those tanks to make drinking water. The pressure just from the DI/RO system and going through the alkaline filter will take hours to fill my 3 containers.