S2 Boilers No Heat

[svennn]

I'll try to provide as much info as I can in this post.

I have an S2 that I bought in 2008 from Chris' Coffee. It's been a great machine.

I've had my 2nd ever problem with it this week. When I turn it on nothing heats up. The machine is on a dedicated 20amp circuit and plumbed in. The the lights and electronics power up as usual but neither boiler heats.

Typically the brew boiler will warm up and then I'll hear the steam boiler fan kick in. Now....nothing.

So where to start? How common is it for both heating elements to go bad at the same time? I have no problem pulling it apart to work on I just need some direction.

Thanks.

Steve

[chas]

As you noted the brew boiler always heats up before the steam boiler will turn on. So the problem is most likely just in the brew boiler circuitry.

The first and easiest thing to test is to check the voltage across the brew boiler leads when you turn it on. If there is 115VAC there then the brew boiler element is shot and you can stop there. If this happens, you can also try one additional test to validate the conclusion. With power off and the brew boiler element's power leads unplugged, check the resistance across the element connectors. It will probably read infinity.

If there is no voltage across the brew boilers leads, then it could be that the triac board is toast. One of the easiest ways to test for that since both boards are identical is to either swap the boards or just swap all the wires if they are long enough. If that is the problem, then the brew boiler will heat up but the steam boiler won't. Should this be the case you can at least make coffee until you can order a new triac board and replace it.

BTW: If you leave the machine on for more than 5 minutes, do you get an alarm?

[svennn]

Great.

I'll try and check the voltage tonight. It's good to know for sure that the brew boiler not heating will stop the steam boiler. I had a suspicion.

I did not have an alarm. Should I have?

[chas]

I did not have an alarm. Should I have?

Good question. Under the temp probe alarm it indicates that there should be an alarm indicating a temp probe failure if the temp does not exceed 60C after being on for 5min. However, if the temp does not exceed 60C for 5 minutes I am not sure how the software knows whether it's due to the heater element, the temp probe, or the triac board failing.

[svennn]

Thanks.

I'll do some testing and pay more attention to an alarm. I'll report back with what I find.

I did not have an alarm. Should I have?

Good question. Under the temp probe alarm it indicates that there should be an alarm indicating a temp probe failure if the temp does not exceed 60C after being on for 5min. However, if the temp does not exceed 60C for 5 minutes I am not sure how the software knows whether it's due to the heater element, the temp probe, or the triac board failing.

[svennn]

I have everything apart.

I'm getting 25VAC on the boiler. If I unplug the leads and check the resistance it reads 35 ohms.

One point of clarification, you said if I have 115VAC than the element is bad. Did you mean if I don't get 115VAC?

Thanks again. It's a huge help to the input.

As you noted the brew boiler always heats up before the steam boiler will turn on. So the problem is most likely just in the brew boiler circuitry.

The first and easiest thing to test is to check the voltage across the brew boiler leads when you turn it on. If there is 115VAC there then the brew boiler element is shot and you can stop there. If this happens, you can also try one additional test to validate the conclusion. With power off and the brew boiler element's power leads unplugged, check the resistance across the element connectors. It will probably read infinity.

If there is no voltage across the brew boilers leads, then it could be that the triac board is toast. One of the easiest ways to test for that since both boards are identical is to either swap the boards or just swap all the wires if they are long enough. If that is the problem, then the brew boiler will heat up but the steam boiler won't. Should this be the case you can at least make coffee until you can order a new triac board and replace it.

BTW: If you leave the machine on for more than 5 minutes, do you get an alarm?

[chas]

No I meant if you have 115V and the boiler doesn't heat the element is bad. Same as if you plug in a lamp and the light doesn't come on the bulb is probably bad.

In this case you DON'T have 115V so the element is probably OK. I would try my 2nd option to swap the triac boards. Those triac boards use a signal from the controller board to turn on the Triac which switches on the 115V to the heater element. This isn't happening.

[svennn]

Right, I understand now.

Any tips on location and access to the Triac board? Facing the back of the machine on the left below the black box? The box itself has a small diagram on it and labels the Triac for the two boilers. I don't don't see how to get access to the board below the box. I also don't want to just randomly move plugs around without knowing I have the correct ones.

[svennn]

I just did a google image search which turned up your pictures on this site. I removed the small flat metal piece on the front of the machine and now see the two boards. The steam boiler Triac with the fan under it is in front.

So to test the Triac, swap the two plugs on each board over to the other board? That is it?

[chas]

That's it. If the brew boiler triac is shot, then after the swap, the brew boiler will work fine and the steam boiler will not heat.

[chas]

I had a failure myself a few hours ago. The Vacuum Breaker Valve popped wide open. I was lucky to be in the next room and heard the water running off the counter and onto the floor. Fortunately, I keep a couple of spares so as soon as the machine is cool enough to work on I should be back up and running.

[chas]

BTW: If you do need a new triac board, they are $36.

http://www.chriscoffee.com/La-Spaziale- ... p/7388.htm

[svennn]

That was an exercise in frustration. I got all 4 wires swapped over and fired it up this morning. Nothing from the brew boiler but the steam boiler heated up.

I think there is a good chance I mixed up some of the wires. I should have labeled them before removing them. With such limited space I didn't see how I could. Now I need to figure out the next step.

That's it. If the brew boiler triac is shot, then after the swap, the brew boiler will work fine and the steam boiler will not heat.

[chas]

If the steam boiler is heating up first, then it sounds like whichever triac that now has the power leads going to the steam boiler is connected to the wire from the controller board that turns on the brew boiler.

I can't draw any conclusions yet about whether the back triac board is actually bad or not. If you have the wires wrong, then it is unclear if the power leads are still connected to the original boards and the control wires are swapped or vice versa.

IF the rear triac (one for brew boiler really is bad) then the only way you could get what you are now seeing is if you left the power wires connected to the original boards but swapped the control input wires.

[chas]

BTW:

Since you swapped the wires and not the boards, if you are actually running the steam boiler off the rear triac, don't let it run for too long. When the back triac is running the steam boiler, the cooling fan is now under the brew boiler triac instead of under the steam boiler triac. The triac running the steam boiler is the one that needs the forced air cooling.

[svennn]

I turned it off as soon as I saw what was happening.

I wish the 4 wires were color coded in some way. I guess I'll call Chris' and see if they have some sort of wiring diagram.

I really need to figure out which wires are power and which are control.

[chas]

Did you review section 6 of the manual? I doubt CCS has anything more than that.

[svennn]

I do have that. My best bet will be to use a multimeter to determine which is power and which is control.

I can't wait to figure it out. I'm using my old Expobar while this is down and there is a huge difference in taste.

Thanks again for the help. I won't be able to work on it anymore until next week.

Did you review section 6 of the manual? I doubt CCS has anything more than that.

[svennn]

I'm back and starting over. I have spent time tracing all the wiring and have a pretty good grasp of the order of things. I removed both of the Triac boards so that I would have better access and also so I could test each.

All tests with the multimeter yield the exact same results with both of the boards.

With the machine boiler ON I get no heat and 122VAC across the heating elements. Then I unplug the machine and the leads on the element and I get 13 ohms.

Did you review section 6 of the manual? I doubt CCS has anything more than that.

[chas]

In that case it does sound like you need to replace the group boiler heater element. When ordering it, don't forget to also order a new gasket for the back side of the boiler that you'll need to unscrew.

Strange that you only measured 25V the last time and now you see 122V. However, if you have 122V across the boiler leads and it's not heating up it's got to be the heater element.

[svennn]

I've double checked the measurements a few times.

I get 25V when I measure with the machine plugged in boiler off. That must be the mistake I made.

I'll call up to Chris' and order my element today.

Thanks again.

In that case it does sound like you need to replace the group boiler heater element. When ordering it, don't forget to also order a new gasket for the back side of the boiler that you'll need to unscrew.

Strange that you only measured 25V the last time and now you see 122V. However, if you have 122V across the boiler leads and it's not heating up it's got to be the heater element.

[svennn]

Good news and bad news for me.

I installed the new element today and everything heats up as normal.

The bad news is when I press the brew button I get flashing lights but no flow. When I press the double button the 94,95,96 lights blink one time then go back to normal. Must be an electrical connection. The steam boiler works as expected.

Any idea?

[chas]

Interesting. What happens if you press the Single Cup button?

[chas]

I assume that this is what you are seeing:

5.1 Coffee Group Water Dosing System Failure
This is a non-blocking alarm. When the flow meter isn't working properly or when the coffee
grind is too fine, this is indicated by the turning on of the lights 14-15-16; if you are making
one coffee dose, and the lights 17-18-19 if you are making two coffee doses.
This alarm is actually useful when back flushing as an indication of when to turn off the pump
and allow the 3-way valve to operate.

This means that either the coffee is ground too fine, the volumetric doser has failed, or else you've inadvertently disconnected the wire to the volumetric doser.

2015-07-10_19-14-23.jpg (28.12 KiB) Viewed 25313 times

On the other hand you could have knocked a chunk of mineral deposit loose while replacing the group element that is now lodged in the volumetric doser vanes so that they can't rotate. To check for this, shut everything down, let it cool, disconnect the wires and pipes from the volumetric doser unit, then remove the screws from the top. You should then be able to inspect inside the body of the unit and look for detritus that should not be there.

[chas]

Also, when you press the one-cup or two cup button does the solenoid click and/or the pump turn on? If not you might want to check to be sure you didn't knock the wire off the solenoid.

solenoid.jpg (35.38 KiB) Viewed 25313 times

[svennn]

No click or anything from the solenoid. Just the corresponding lights from the double or single brew button.

Also, when you press the one-cup or two cup button does the solenoid click and/or the pump turn on? If not you might want to check to be sure you didn't knock the wire off the solenoid.

solenoid.jpg

[chas]

OK, the light bulbs finally went off and I remembered what causes this. From the V2 FAQ page:

When I press the two cup button, lights 17 18 and 19 flash once and then back to the current temp light or when I press the one cup button lights 14, 15, and 16 flash once and then back to the current temp light. The pump never turns on.

These are the classic symptoms for those VII or VII Mini users that do not have the optional timer but have the timer enable switch set to ON on top of the black controller box. This switch MUST be set in the OFF position if you don't have a timer otherwise you will get the exact symptoms noted above.

To access this switch you need to remove the top cup warmer tray. This is done by removing a single recessed screw in the front center of tray. Once the tray is removed, look inside the machine for two switches on top of a black box. This is on the right side when facing the front of the machine. One switch is marked 15/20 and is set to whether you are running in 15A or 20A mode. The other is labeled On/Off. If you do NOT have a timer this switch MUST be set to OFF!

[svennn]

Bingo. That fixed the problem.

I can't thank you enough for all the help.

[chas]

Excellent. Glad to hear you are back up and running.