Isomac Tea not drawing water

[pjcheng]

I have an Isomac Tea. It is about three years old. When I start the machine, the pump starts to function. However, it is drawing water very very slow at first, then the water stops flowing. The pump is still running, but no water is flowing. Eventually, it stopped. I got a new pump and installed it. The problem still exist. Can anyone suggest what I can do next? Where is the problem? I need my espresso fix. Thank you.

[HB]

Does your machine have a water softener on the end of the intake tube (link)? Sometimes they clog.

[pjcheng]

Dan,

Thank you for your reply. I have always use reverse osmosis water for this machine. When I changed the pump, I did find any build up.

I am thinking is there a way to flush the system to get rid of any trapped air.

PJC

[another_jim]

Some line is clogged. Here's some diagnostics:
1. Run water from the hotwater tap. If the boiler refills properly and the pump stops running after a few seconds, goto 3.
2. If the boiler didn't refill right, replace the intake hose.
3. Run a the pump from the group without a pf, and check the return hose. If water is flowing back to the tank under no pressure, one of the over pressure valves is shot.
4. Do a blind filter shot. If the pressure doesn't rise to normal against a blind filter, again one of the opvs is shot.
5. If the pressure rises to normal very slowly, or doesn't rise at all, the line from the pump to the group is blocked. This is a major headache, since you'll need to disassemble the piping and group and look for it.

[pjcheng]

Thanks for the suggestion. Will give it a run.

[pjcheng]

Can some one post a picture of the back of Isomac Tea? I replaced a crack 'T-connector' and need to know how the water tubings are connected to the 'T-connector'. I am missing a connection. Thank you.

[HB]

Tea owners were regularly reporting cracked Y connectors a couple years ago on CoffeeGeek (e.g., ISOMAC TEA leak, Isomac Tea modification, and more recently with Tea is leaking AGAIN). And oddly enough I found no pictures. Oh well, I happen to have a picture of the backside of the Isomac Rituale from an earlier review:



They are internally similar. Jim explains that the Tea has two over-pressure valves, a non-adjustable safety one and the adjustable brass one shown in the forefront of the above photo.

[another_jim]

The picture Dan posted could be of the Tea. The Y connector is taking hoses from the two overpressure valves. The large one closest to the lens is the adjustable one (turn the shank with the hose barb), the other hose is originating at the nonadjustable safety valve. I can't post my pictures right now, since the disk (and computer) they are on has crashed. Once I have the new disk, I can get everything off the backup; but that will take the weekend to sort out.

If the pump is not drawing,

1. check the boiler refill by running water from the water tap. If the boiler refills, i.e. the pump stops, the pump is fine, and so is the first part of the line.

2. now run the pump and check the run off back into the tank via those hoses -- if it's around 2 ounces in 20 seconds you have full pump pressure, and the line to the group, or the group itself is blocked. If the run off is a lot more, like 3 to 4 ounces in 10 seconds, one of the pressure relief valves is stuck open.