Tip # 36, from da Lone Ranger: On how to ruin your water tanks.......

You cannot pressure fill these light poly tanks. There have been suggestions about making up a tight fitting assembly to pressure fill your tanks faster…. This will ruin the tanks. The vent (on top of each tank) is smaller than the hose you can push down inside the filler neck, and if you seal it off to push in the water at a faster rate, the tank swells as the air cannot be expelled fast enough through the smaller vent on the top of the tank. This swelling eventually causes the tank to fail, even if you turn it off as soon as the first sign of water coming out the vent. It could work if the fill rate was slow enough, but at a high volume/rate, it stresses the tank. Air will compress a bit and blow out the smaller vent on top of each tank, if the rate is not too fast…. But water in this practical sense does not compress… As the tank fills up, and water starts to spurt out the top tank vent, the tank swelling will exponentially increase rapidly, as the vent on top is smaller than the filler hose.. This is also the case if you have too large and tight fitting hose jammed into the filler neck, and the water spurts violently back at you, same situation, and you are grossly shortening the life of your tanks… And getting wet…

We see them split at seams, fittings strip, all kinds of failures as a result of this. Now, the best way, is to use something like a piece of the grey hot water plastic flexible pipe that your HWS in plumbed in. It has an (I.D.) of about 3/8” and outside (O.D.) is still a little less than ½ inch. It is stiff enough to find the hole in the filler easily, and I just put snap fittings on it… But it also just slips up inside most hoses with a reasonably snug fit… And the most important thing is that when the tank is full and the vent on top of the tank is spilling water steady, it still will not spit the water back at you out of the filler. It just overflows and runs out gently onto the ground as there is plenty of clearance. This means you are not pressurising the tank, and so are not stressing it to failure on the first or tenth or hundredth time you fill the tanks… But trust me, it happens.

Better to have the vent on top of the tank overflowing onto the ground and the filler overflowing gently onto the ground when you are distracted by something and leave it running full… So, don’t use too large of a piece of hose to block off the small opening in the Filler! You want it to run out when full and you need to open another tank, not spurt out violently as that is too tight of a fit! As to one well meaning suggestion about putting a taper of tape on the hose to jamb it down the filler hole and seal it so you can pressure fill it at a high rate…. Three things: No, No, and furthermore No!…. It will blow the tank eventually… Maybe not the first or tenth time, but it will happen. We have a large stack of them out back from just that. I hate to throw away the carcasses so we save them for ……? Oil change pans, liners for …. Anyway, we have a stack of them from doing just that…

Cheers from the “Lone Ranger”, out on the Frontier…