Above ground pool assist needed...? Does anyone know what would cause a sand filter in an above...

Does anyone know what would cause a sand filter in an above ground pool to blow sand backbone into the pool?
Heat pump section is working but not heat...
mine did this and the guy told me its lead to i had added 2 much sand and that it would work itself out.it did...

Do they receive in-line surge protectors?
you need to back flush the filter and system, the filter is probilly cloged.
I run out of saline for my freezing...
nope.. IM SURE YOU CAN CALL A NUMBER ON THE instructions.. lol
Is in attendance such piece as a fireproof...
Answers:    A broken lateral,too much sand,or a faulty backwash valve heres a page devoted to sand filter: http://www.swimming-pool-information.com... and another page on filter problems: http://www.swimming-pool-information.com...