Dissolve the Main Drain? No Problem!
A phone message 'You won't believe this' along with a Winter Park address was about all the info we had on this call.
The pool was completely empty; not unusual for a total pool renovation job.
'But it was filled two days ago' explained the contractor. 'I filled this pool two days ago and this morning and it was empty, just like you see'.
The main drain cover looked like it had been melted in a fire. The plastic main drain sump was brittle enough to shatter. There was black sooty sand under the sump, the droopy end of a 2 inch PVC pipe and not much else.
One of my guys had seen this problem before. 'Any trouble with the chatt guy?' he asked. The contractor looked startled. 'Well, he's got a large section of deck to chip up and do over and I'm holding his check until we get that worked out' the contractor admitted. 'We had some words, yeah.'
'Only one thing I know can do this' my guy stated. 'They use it to clean chatt mixers when people forget to clean the rental equipment; it can dissolve dried resin.'
It's a mix of a dibasic acid ester, hydroquinone, tartaric acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid, hydroxy carboxylic acids and a few other things you wouldn't want in your neighborhood. Heavier than water and not water soluable, when this material is poured into a pool it gravitates in a cloud to the deepest area and proceeds to dissolve anything, like plastic, that contains a resin.
How much would it take? No idea, but the stuff comes in gallon cans.
So, how do you repair a melted main drain?
We filled the main drain void with concrete and topped the repair with a new main drain cover to ease the anxiety of a pool owner used to seeing a main drain cover sitting there. The contractor bought a vacuum-side pool cleaner with the chatt mans money (who never reappeared). We cappped the old main drain line at the equipment and tied the original cleaner line (along with the skimmer line) to the suction side of the pump.
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