Similar problem with my new Thor Vegas 25.4. I get hot water when I'm not using city water but the water pump. When hooked up to city water, might get hot water in bathroom sink, sometimes, but not in sink to do dishes. Just bought a meter to control the PSI at the water connection and will try to fool around with that next time I'm out but what you say about number of turns in plumbing might be "it".
Safe-T-Plus Steering Control
Rear Track Bar
Progressive Industries EMS-HW30C Electrical Management System