I have a Delonghi Magnifica Rialto EAM4500 coffee maker. Recently it has stopped frothing milk. Per delonghi I have replaced all of the gaskets that connect between the milk container and the unit. When we go to froth milk we get tons of steam from the milk container, but no milk is ever dispensed. If I attach the hot water spout I get plenty of hot water from it.

I purchased a unit second hand for my wife's birthday today. It's only 4 months old, got it home, tested it, same problem... No froth!

I've read all the posts here and all were very helpful troubleshooting guides however they did not solve the issue.

Understanding how the frothing mechanism functions is half the battle in figuring out the solution. It's a simple vacuum type system. No doubt you've read about checking the orings. This is definately the first thing to check however if this is not the reason then consider the following.

The larger of the white tubes that has the red and black oring inserts deep into its port on the tap. Why? It pushes steam past the milk pipe directly into the chrome frothing tube which causes a vacuum essentially drawing milk up it's hose creating the froth. What you can't see without further investigation is that on the underside of the tube centered between the red and black orings is a small hole. This hole is responsible for drawing the milk upwards. If this is blocked, and it probably is then no milk and no froth. Use a really small screwdriver to carefully clean the white tube both from the front and the little hole underneath.

So in conclusion. Any air leak between the red and black orings will prevent the vacuum required to draw milk up the tube and alternatively any blockage of the milk channel will also obviously prevent the flow into the frothing mechanism. Hope this helps.

Frothing jug
For milk frothing issues, soak the milk jug cover in hot water and rinse several times. If it has a froth control that can be removed by sliding in the direction of travel towards the edge whilst jiggling it gently up and down. Clean off the little o-ring with a toothpick, be gentle. The control should easily slide and click back in place when done.

Froth still no good? Examine the milk coupling to ensure the o-rings are in the right spot and are pliable and undamaged. There should be an o-ring (usually green) on the top spigot, a (black) o-ring at the front of the bottom spigot and a (red) oring at the rear. The groove halfway along the spigot should be clear. Now with the toothpick and a hot moist cloth clean all the crud from the milk coupling, especially inside the smaller spigot. Check the tiny hole at the back of the larger spigot is not blocked.

Check the flow from the hot water spout is good. If not, there are internal issues, try descaling. If it is, test the frothing jug, if it is still weak either the jug cover or the milk coupling needs to be replaced. Get them to try a known good test jug at your local coffee service center to find out which, most will be happy to do this at the counter.

General Service
To keep these machines running right clean them out properly a couple of times a week, keep the brew unit serviced and always use the clean button on the frothing jug until the water runs clear.