Back Wash Manifold Rig

[pool_clueless]

So, I had to drain my pool to get rid of some metal staining that just wasn't going away. My back wash dumps into my yard, which drains down hill into my neighbor's yard. Not good for good neighbors. So what to do? I bought the 2 inch back wash hose at lowes. I needed 150' of it, so I bought three of them. connected them together with 1.5" pvc pipe and hose clamps. It lasted about 5 minutes, then started springing leaks everywhere. I have to pump uphill to get to the street storm drain, so the hose has to take a little bit of pressure. My sons and I chased leaks for about 3 hours and then gave up, deciding to come up with a different solution. Being the electrical engineer by degree, I was determined to re-engineer this. So I gathered up the hose pieces that had split apart, shoved them in a trash bag, and off to lowes I went to get my money back. I was miffed at lowes, so I went over to Home Depot. While I was there I started searching the plumbing aisle for ideas. Then it dawned on me, garden hose fittings. 3 garden hoses will give me an equivalent volume of 1.5 diameter pvc pipe, or close enough to it. So I bought 3 pvc hose fittings, 3 1.5 x 3/4" x 1.5" T fittings, a 1.5" cap, and a ball valve. I had some 3/4 pipe and some 1.5 pipe at home. So this was the result:

I had plenty of garden hose laying around to make three 100' runs. So i bought some cheap 50' hose and completed the length for each hose to the street drain. Cranked up the pump and had the pool drained overnight. I plan on using this from now on to back wash. Hope this helps anybody else who doesn't want to spend $200 on discharge hoses if you have a long run to your drain point.

 

[jblizzle]

Interesting setup.

But I want to point out that it is generally not a good idea to backwash a lot of water through a DE or sand filter. Hopefully you were really using the waste option.

I also have a little bit of concern about it being effective when doing a backwash, you are adding a fair amount of back pressure so it may not backwash as well and hopefully it will not clog up.

 

[pool_clueless]

I drained it thru the waste option. I also monitor the pressure gauge on my filter when I backwash just for that reason.

 

[jblizzle]

Great! Glad it is working!

 

[pool_clueless]

And speaking of backwashing, I never backwash longer than it takes for the site glass on my multiport valve to show clear water. Usually only takes about 2 min or so. When we had a lot of pollen and tree debris at the beginning of spring, it would take a max of 5 min.

But here is a question, Do I need to use the rinse option after backwashing a DE filter? I am not clear on what the "rinse" option does.

 

[jblizzle]

You should be alternating between backwash and rinse multiple times. I have done this 4-5 times, opened the filter and still had all kinds of DE stuck in there.

See: Use and Care of DE Filters

 

[pool_clueless]

So after reading use and care of DE filters, and going off of what the filter manual says, I am wondering if I am backwashing too much. I never get my pressure gauge to read more than 22lbs. That is the clean pressure. I have been backwashing and adding DE once a month. Manual says to do it once a month. So, is there a risk of overloading the filter with DE if I backwash too much? Also, I am pretty sure the gauge is working well - when I run the pump at half speed it reads half the pressure, 11lbs. I have another guage in my spares, just don't want to go thru the hassle of changing it if I don't have to.

 

[jblizzle]

There is certainly a risk of overloading the filter if you backwash often and add back in too much DE. And there is no reason to backwash unless the pressure is rising and the flow rate is decreasing.

Pump at half speed will not read half the pressure. I see 11 psi on high and basically 0 psi on low (half) speed.

Did you also read the link in that article about how to break down the filter? Because I would recommend you do so if you have been packing in the DE.

 

[pool_clueless]

I broke the filter down and replaced the grids last fall. Original owner of the house must not have ever done this because the grids were so bad that they were not holding any DE at all. It was just blowing back into the pool. Once I replaced the grids and recharged the filter with DE, I never got more than 22psi on the gauge at full speed. Several weeks ago when I drained the pool, I also backwashed and drained the filter until no more DE was coming out. I wasn't planning on breaking it down again until this fall. My water is crystal clear by the way. I can read the date on a quarter in the deep end with binoculars.