root, the slideout system (HWH, Powergear or Atwood) should still have a warranty that covers a problem like you have. It sounds like you may have an HWH system with a bad solenoid valve. HWH has a three year warranty and most all RV repairs facilities has a working relationship with HWH. I recommend you get a shop to diagnose and help you out with correcting the problem under the slideout system manufacturer. Good luck and keep us posted.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7