hankmillerusa
Member
Help!!! I have been RVing for many years and dont think I am doing anything wrong before having to look in owners manual (lol), but it seems I can not get black tank to ever drain past 3/4 full. I have a Cyclone 4250 with two places to drain tanks, Gray water tank 1 box and Gray water tank 2 box. Both have 2 valaves. I am assuming if you open all four valves, both gray tnks and black tank will drain at same time. I seem to have good flow coming out of drain pipe. Why isnt the black draining more than 3/4 tank? I am thinking, possible clog or bad sensor. I dont know, but dont want to get caught on a trip where I cant use toilets. Please tell me what each valve does in each tank box. And how do I specifically drain black tank so I can tell if it is sensor or clog? Thank you very much. Hank Miller