Hi all -

I ran across a test for the boiler fill solenoid valve by pulling the power to the pump and then turning the machine on. The solenoid is supposed to engage, opening the valve. The ECM Giotto uses a Giemme RLO IE/IS/4C/F controller and a Parker 2 way with the WB4.5 coil.

On initial testing the Parker made a clicking noise when the machine was switched on, but heard nothing when switched off, as if it barely opened momentarily then closed. Not sure, but it seems that it should have been held open until machine is switched off. No experience with how these circuits are supposed to work, so apologies if I'm missing something obvious.

I opened the Giemme and drilled down a bit further. Found three relays, two of which are clear - RL1 and RL2 that seem to be used for the solenoid. No schematic so not sure. Test results follow.

Machine off - RL1 and 2 are both open.
Switch on - RL1 closes then RL2 closes momentarily, the solenoid clicks, and then RL1&2 both open. Sometimes RL1 opens before RL2 can close, and sometimes nothing happens.
Switch machine off and RL2 clicks.

Hopefully someone can make sense of this. My best guess is the controller is bad.

Thanks for any assistance.

Solenoids commonly turn on much harder then they turn off so it does not seem at all surprising that it would be louder turning on than turning off.

Ira

The person who really knows this controller would be jpboyt, but I checked and looks like he hasn't visited this forum in over a month. EricS is another who might have some expertise here.

My controller is different, but I'll weigh in with what I think FWIW. Hopefully someone with more direct experience will chime in.

I took the liberty of annotating an image from the farmroast post ( Giotto Problem ) about an ECM Giotto with this type of controller:

(All I did was add those red numbers so that it's clear which wires correspond with the numbered labels on the circuit diagram.)
1 - hot
3 - neutral
4 - pump
5 - autofill solenoid
6 - pStat/thermoswitch/element
7 - group lever switch
8 - ground (reference ground for sensor probe circuits)
9 - boiler probe sensor
10 - reservoir sensor

Does this look like yours?

If so, here's how I would troubleshoot.

I assume you're experienced at working with energized circuits. You do have dangerous voltage on many of those wires into the controller. (Or as jpboyt would say, Mr Snappy lives here.)

First, get the low voltage leads (wires at 8, 9, and 10 in the pic) out to where you can safely remove and connect them to a common ground without getting your fingers near anything hot. Initially start with all three connected to that common ground to simulate a full boiler and a full reservoir. If your boiler is empty, disconnect the element so that it doesn't overheat and burn, and disconnect the pump.

When you turn it on, the K1 relay should switch over to the other contact, and K3 should close.

When you un-ground the lead that normally goes to the reservoir (Pin 10, S. Serb) the K1 relay should switch back (and I believe that the K3 would open also.) You can ground and unground the wire and hopefully hear the relays click. May be a delay.

When you un-ground the lead that normally goes to the auto-fill (pin 9, S. Liv) the K2 switch should close, energizing the pump and auto-fill solenoid. And I'm pretty sure (don't know for fact, though) that at the same time K3 should open (protecting the element from an empty boiler.) When you ground and un-ground this one, you probably will notice a delay, maybe even a few seconds.

Listening for clicks might be good enough. If not you may want to wire in a voltmeter in turn on each of the wires out of 4, 5, 6, and 7 to be sure your relays are closing as expected and that the contacts are good.

cuppajoe wrote:Switch on - RL1 closes then RL2 closes momentarily, the solenoid clicks, and then RL1&2 both open.

I'm not completely clear about which relays RL1 and RL2 refer to, but that does seem a little odd. Make sure you have a good ground, so that the level sensor wires and the ground wire from the controller are all well connected to a common ground. There may be some extra smarts coming into play here I that don't know about.

p.s.
Here's another thread from someone who had troubles with this controller: Gicar controller blown again - wiring help?

Thanks guys.

I poked at it a bit and finally figured out how to test the solenoid by running just the valve assembly with the two back flow preventers. Took a bit of head banging to work out how the thing was engineered, and figured out the grounding the fill sensor lead thing.

It seems that it is working properly at the moment. With the fill sensor lead grounded, water only routs to the HX direction and not in the boiler direction when the group switch is activated. There is still very little pressure coming out of the HX side of the assembly, even with the boiler side closed. Before doing these tests I had drained the HX tube and the amount of water was about right for the top of the HX injector, so it seemed the HX tube wasn't filling all the way with any sort of pressure.

The machine seems to be a 2002 and guess it's the original pump. Wondering if the pump is the culprit.

Wondering if the pump is the culprit.

Now that your labooooooratory is all set up, ya need to measure pump pressure vice flow and compare to this:



Unless you are 100% positive that the controller is working as intended, I would be inclined to send it off to jpboyt for a look-see - http://www.yelp.com/biz/boyt-enterprises-wilkeson . Furthermore, I would THINK ABOUT letting that 15 amp relay take a long rest and install an SSR controlled by a much simpler pstat and let the SSR do the dirty work of controlling the heater.

Thanks for the input Eric. Well, turned out to be the pump. Seems it had been disassembled prior to me getting ahold of it and I just put it back together as it was. The small O-ring that seals the through-tube on the armature(or whatever it's called) had been improperly installed. Was all set to replace it with an EX5 I had sitting around, but pulled both apart to see what the differences might be and noticed the wayward seal.

Put it in it's proper place and all is good. So now the machine is up and running and so far the shakedown runs have been good. Except...

Was reinstalling the priming valve assembly on the pump outlet and it deconstructed on me. Was doing my best to avoid over tightening, but guess the 11 year old plastic had had enough. Poor choice of material, all things considered.

I now have the outlet tube attached directly to the pump outlet. Any problem with using it this way 'till I get the part in?

Thanks again for everyone indulging me in all this. It has been a good learning experience and now have a better idea how these things function. My brain hurts.

The priming valve/deaeration valve is sealed to the pump outlet by an o-ring:



There is no problem in temporarily running with it out of the system. Replacement valves do not normally ship with an o-ring but your local hardware store can help - the correct size is a "-010" (6.07 mm ID x 1.78 mm width)

erics wrote:Now that your labooooooratory is all set up, ya need to measure pump pressure vice flow and compare to this:

<image>

Unless you are 100% positive that the controller is working as intended, I would be inclined to send it off to jpboyt for a look-see - http://www.yelp.com/biz/boyt-enterprises-wilkeson . Furthermore, I would THINK ABOUT letting that 15 amp relay take a long rest and install an SSR controlled by a much simpler pstat and let the SSR do the dirty work of controlling the heater.

Hi Eric -

Thanks for all your input on this. The more I look at the situation with the Sarai, more unhappy I get. It's just hanging there by the tube and in order to get the side cover on you have to just force it on and cram the Sarai between it and the water tank. Very sloppy work on the part of whoever did the mod.

I have a "SSR-40 DA" SSR with an input of 32VDC and load spec of 24-380VAC, rated at 40A/250V. What PSTAT would you recommend to run with it and the Giotto. As it would be bypassing the Giemme's relays, would also need to know where to tap the PSTAT into the system. Any links to play by play instructions would be most helpful.

The machine is up and running now and the first coffee out of it was not too bad, quite good in fact.

David -

That SSR, having a control input of 32 VDC (probably 3-32 VDC) is intended to be used with a PID having that signal output. SSR's installed in espresso machines (Quickmill, Isomac) have a control input of 120 VAC which is what you would need if you went that route.

The ECM Giotto, I BELIEVE, was originally fitted with a MA-TER pstat because the "heavy-duty" switching is performed by RL3 in the Gicar control box. You can download a Quickmill electrical schematic from my FTP site (below my sig) and modify it to reflect your existing machine.