ECM Giotto diagnosis assistance needed - no green light

#1: Post by **wimpee** » May 5th, 2013, 1:13 pm

Hi - my aging Giotto all of sudden will not start. No green light, no heat, nothing.

It has the newer Rocket control box and wiring harness.

Power is present at control box and goes on and off with the switch.

Thermal cut-off appears fine.

What should I check next? I'm getting frustrated with control box issues

#2: Post by **homeburrero** » May 5th, 2013, 1:54 pm

How are you verifying that it has power? I think you have a dpst switch that switches both hot and neutral see diagram: /downloads/ ... .03.09.pdf

If the neutral side of the switch was not working you would see voltage coming out of the hot side of the switch (measured against ground), but no light and no heat because the neutral side is open. With the machine unplugged and the switch on make sure you have continuity between the neutral wire on the cord side of the switch and the neutral wires that lead from the switch to the lamp, pump, element.

#3: Post by **mikekarr** » May 5th, 2013, 9:52 pm

Have you checked the water level in the tank, or made sure that the probes are making contact with the sensor? This has bitten me before.

#4: Post by **Tonkajoe** » October 13th, 2013, 4:07 am

Hi, did you ever get this fixed. Mine just did this same thing this morning. Was working fine and then nothing.

thx

Wade in Calgary

#5: Post by **homeburrero** » October 13th, 2013, 1:28 pm

I'm also curious also as to if/how the OP resolved this.

Note that the OP said his Giotto had the newer style of wiring, which would imply that his light was fed by the on/off switch rather than being connected to the controller. The links to the wiring diagrams that I posted above show one version of the Giotto (with the RL30 controller) that has the light wired through the controller.

Wade: I bet your Cellini has a light wired through the controller. (And may even have the feature where it will blink when the reservoir water is low?) So you should make sure your reservoir sensor is working right, because as mikecarr pointed out, that is prone to flakiness.

(Of course, be sure you have power - haven't simply tripped a GFI on your plug.)

P.S.
On the Rocket Giotto circuit diagrams that I pointed to above, it shows the newer wiring, and a diagram for a "RL30 modification pre-2005". Some older machines (including my 2002) have wiring very different from either of these two diagrams. If anyone needs an older wiring diagram (for machines with GiCAR 9.9.04.77G) let me know and I'll draw and post a pic of mine.

December 1st, 2013, 5:06 pm

Sadly, OP has been working a lot and just had time to return to this today.

There is continuity on both sides of the switch when it is in the on position.

What's next?

#7: Post by **homeburrero** » December 2nd, 2013, 10:48 am

wimpee wrote:Sadly, OP has been working a lot and just had time to return to this today.

That's a long stretch without coffee.

wimpee wrote:There is continuity on both sides of the switch when it is in the on position.
What's next?

If your switch is good and the light does not come on (and assuming the light is good) then you don't have the wiring that I thought you had. The online diagram for the newer Giottos that I was looking at looks like this:

I bet yours is different - has the light connected somewhere in the circuit off the Gicar. So if that's true, I can't help much without knowing how the machine is wired. But mikecarr's tip about the reservoir sensor is a good one, especially if you have the old type with two long probes into the tank (as seen in this post: Giotto overpressure problem - boiler won't stop heating .) Make sure the connections there are good, especially where the sensor probe rests on a metal cradle. You can sometimes press and wiggle that side and see the machine come on.

#8: Post by **homeburrero** » December 2nd, 2013, 10:58 am

Oh, and I guess I should mention that the water in the reservoir has to have some electrolytes - if it's 100% distilled, that reservoir probe (and the boiler probe as well) may not work.

#9: Post by **Randy G.** » December 2nd, 2013, 11:17 am

Here is the schematic with the switch schematics changed. To me, the diagram in the previous post of the wiring seems to indicate that the A and N are shorted when the switch is activated.

December 2nd, 2013, 12:12 pm

Randy G. wrote:To me, the diagram in the previous post of the wiring seems to indicate that the A and N are shorted when the switch is activated.

Yes, but which obviously can't be true, so one must interpret that diagram (which comes in a parts catalog from a couple Giotto parts vendors) to simply be a confusing way of representing a standard DPST switch. I've seen it represented like that in other diagrams, but your way is much better (and more common.)