Delonghi rialto eam4500: Lost Hot Water Spout. Where to get one?

Based on the information provided, it is possible that there is an issue with the machine's internal circuitry or wiring. It could also be a problem with the control board or the sensors that detect the presence of the milk jug or hot water spout.

One possible solution is to try resetting the machine to its default settings. To do this, turn off the machine and unplug it from the power source. Wait for a few minutes before plugging it back in and turning it on again. This may help reset any internal settings that could be causing the issue.

If resetting the machine does not work, it may be necessary to have it serviced by a professional technician. They can diagnose and repair any underlying issues with the machine's components.

It is also worth noting that regular maintenance and cleaning of the milk frother and hot water spout can help prevent issues from occurring in the first place. Be sure to follow the manufacturer's instructions for cleaning and descaling these parts of the machine.

Overall, if the issue persists, it is recommended to contact Delonghi customer support or a certified technician for further assistance.

Sounds like milk steam apparatus is clogged. Try to disassemble this portion and clean thoroughly. Descaling will not help this section.

Check the heating coils for proper resistance or no resistance. If the machine is sending a signal to check the coils before turning them on AND it is not getting any resistance then it cannot continue. However if you have the machine plugged in near the microwave oven, then a power surge may have blown the control board or caused it to lose its progamming. The control board is expensive!
http://www.appliancefactoryparts.com/smallappliances/delonghi/esam5500-b-perfecta.html

Delonghi Perfecta won't froth milk or allow hot water to come out from waterspout

Delonghi EAM, ESAM, ECAM, Nespresso

Over time, the continuous heating up of the water used to make the coffee leads to lime scale building up in
the inner circuits of the appliance.
When the appliance displays the message:
DESCALE
you should perform the descale cycle.
Proceed as follows:
• make sure the appliance is ready.
• press the button (the light over the button comes on) then press the button repeatedly until
the appliance displays:
DESCALE No
• Press and the appliance displays the message:
DESCALE Yes
• Press the button to start the descale programme.
• Empty the water tank and add the contents of one bottle (125 ml) of DURGOL descaler plus
one litre of water. For subsequent descaling, use descaler of the same type and brand as supplied
(available from technical service centres authorised by the manufacturer).
• attach the water spout to the nozzle;
• place a container with a minimum capacity of 1.5 litres under the hot water spout (Fig. 3);
• press the button. Descaler runs off from the hot water spout into the container below. The appliance
displays:
APPLIANCE IN DESCALE
• the descale programme automatically performs a series of run offs and pauses to remove lime scale
deposits from inside the coffee maker.
• After about 30 minutes, the appliance displays:
RINSING FILL TANK
The appliance must now be rinsed through to eliminate residues of descaling solution from inside the appliance.
Proceed as follows:
• empty the water tank, rinse and fill with clean water.
• Reposition the tank.
• Empty the full container and then put it back under the hot water spout.
• Press the OK button. Hot water is run off from the spout into the container below and the appliance displays:
RINSING
• When the water tank is empty, the appliance displays the message:
RISRINSING COMPLETE PRESS OK
• Press the OK button and refill the water tank with clean water.
• The descale programme is now terminated and the appliance is ready to make coffee again.
NOTE: if the descaling cycle is interrupted before completion, the appliance continues to display the descale
message and the programme must be started again from the beginning. Empty the water tank, rinse, fill with
clean water and run off a cup of hot water.
IMPORTANT: FAILURE TO DESCALE THE APPLIANCE REGULARLY INVALIDATES THE GUARANTEE.

Delonghi EAM, ESAM, ECAM, Nespresso

Over time, the continuous heating up of the water used to make the coffee leads to lime scale building up in
the inner circuits of the appliance.
When the appliance displays the message:
DESCALE
you should perform the descale cycle.
Proceed as follows:
• make sure the appliance is ready.
• press the button (the light over the button comes on) then press the button repeatedly until
the appliance displays:
DESCALE No
• Press and the appliance displays the message:
DESCALE Yes
• Press the button to start the descale programme.
• Empty the water tank and add the contents of one bottle (125 ml) of DURGOL descaler plus
one litre of water. For subsequent descaling, use descaler of the same type and brand as supplied
(available from technical service centres authorised by the manufacturer).
• attach the water spout to the nozzle;
• place a container with a minimum capacity of 1.5 litres under the hot water spout (Fig. 3);
• press the button. Descaler runs off from the hot water spout into the container below. The appliance
displays:
APPLIANCE IN DESCALE
• the descale programme automatically performs a series of run offs and pauses to remove lime scale
deposits from inside the coffee maker.
• After about 30 minutes, the appliance displays:
RINSING FILL TANK
The appliance must now be rinsed through to eliminate residues of descaling solution from inside the appliance.
Proceed as follows:
• empty the water tank, rinse and fill with clean water.
• Reposition the tank.
• Empty the full container and then put it back under the hot water spout.
• Press the OK button. Hot water is run off from the spout into the container below and the appliance displays:
RINSING
• When the water tank is empty, the appliance displays the message:
RISRINSING COMPLETE PRESS OK
• Press the OK button and refill the water tank with clean water.
• The descale programme is now terminated and the appliance is ready to make coffee again.
NOTE: if the descaling cycle is interrupted before completion, the appliance continues to display the descale
message and the programme must be started again from the beginning. Empty the water tank, rinse, fill with
clean water and run off a cup of hot water.
IMPORTANT: FAILURE TO DESCALE THE APPLIANCE REGULARLY INVALIDATES THE GUARANTEE.

Hi sounds like a blocked boiler. Remove the water inlet line going into the boiler and use a 3mm drill bit and drill the inlet pipe out. Could also be a faulty hot water solenoid. Dazza REPAIRER

Either the grind is too fine and the water cannot go through or the brew unit is blocked.

use 1/4 cup of vinegar and fill pot with cold water, run through machine

You need to descale the machine with descaling solution.
look at following link for instructions

DELONGHI