magtag dishwasher

[vegmate]

I made a post on the appliance section but thought I would also post to plumbing....having trouble with dishwasher cleaning properly. The reason I feel it may be a plumbing problem is because I just had a new dishwasher installed and same problems happening as old one. Thought if I replaced old one problem would go away...it didn't. Soap and food particles left on dishes. Have tried different soaps, adjusted water temp., used rinse aid, checked elevation of hoses, repairman says disposal isn't the problem, tried vinegar, had new hoses connected with new dishwasher so no clogs there, dishwasher fills up and drains correctly but not only is soap left on dishes but soap film left on inside of dishwasher and on bottom coil. Have tried using less soap, but soap film still left. After running complete cycle, if filled again and again, soap bubbles appear at begining of cycle without using any soap at all. I'm at my wits end!
please help, thanks

[HayZee518]

ok let's examine what's changed since you installed the dishwasher...... just the dishwasher, the discharge hose and air gap is the same, the water inlet is the same. I trust the thing is levelled and secure to the floor. Only thing I can figure is the discharge hose that goes to the air gap retained a bit of the previous water and fed back into the dishwasher by gravity. You see the motor acting as a pump really can't totally empty the tub because after the tub is empty there's no water to pump, but when the thing shuts down, what water is left in the discharge hose, because of the air gap, bleeds back into the tub. When it fills up, that water mixes with the new water and has some soap left in it so it washes with used soap and you add more detergent to the new load so it just keeps building. it's miniscule but enough to cause you headaches.