engel fridge

Thanks, I have only used the 240 outlet from the generator for the fridge when running direct

I connected to auxiiary battery on caravan.
The black wire from the 12v supply heated up considerably but because polarity was wrong it didn't blow inline fuse (did melt casing surrounding fuse though)

I am located in Geelong Victoria

Hi Mezza, Any chance of posting a clear photo of the component side & the track side of the Board ? Most boards are repairable, unfortunately im not familiar with Engel Except have seen on other forums an inductor on the board can burn out. I find it annoying that there are no circuits avalable. Ime familiar with Waeco CDF-40 fridge having repared one & drewup the circuit of the board & posted pictures of the PCB & circuit diagram on GreyNomads forum in Techies corner. Un fortunately cant post pics on this Forum. Cheers Daryl

Thanks for your help and interest Daryl. Will endeavour to get picture to you, may take some time as I am only a beginner at this computer stuff. How to you suggest I get the pictures to you? Will I need your email address or will I have to switch over to the grey nomad site? Thanks mezza

OK, well the fella I'm thinking of, who I believe 'knows his Engels' is a bit far from you to be of any help directly... (He's west of Brisvegas)...

However, if you can get no sense elsewhere you may wish to give him a buzz on the ol' dog'n'bone and see what he reckons >> Mark Pennington (Mini 'Fridge Man) 07 46 976666

I'm inclined to think that if the motor still runs, you have a problem other than the power supply...

Regards, Ed C

:)

Mezza its probably at least worth trying Ed C sugestion. As far as I know there is a 240V to 12v power supply then a circuit which drives the compressor(solenoid basicly) with a voltage of about 20V RMS @ about 40Hz. Is there 2 boards in the unit? Its veasier for me to use Grey nomads as you can PM me there & its free to join. Daryl

A Short cycling Engle 40 just cost me $600. This was the second repair in just over 12 months.

That's right just out of warranty and Egle will not help. The previous repair was for the same problem. That repairer identified a problem with the board and charged about $400 again just out of warranty and again Engle did not want to know me.

I would have chucked it but what do you do. Every new product on the market has problems. Any new fridge was going to cost me over $1000 so the repair was really the only option. I think they know they have got you and charge accordingly.

Oh and I told the Engle guy I would tell this story at every opportunity. He reckoned that was up to me.

Duncs

Duncs

I'm sure it has been discussed on EO before but if your Engel was 'newish' when the first problem arose then you would have had grounds for a claim against Engel (or the importer) under 'implied warranty' (Trade Practices Act). Just happened to be reading about it the other day - try a web search.

In general implied warranty applies for 'expensive' items irrespective of the manufacturers warranty. Might be a little late to pursue but if you still have documents/communications from Engel I'd be inclined to enquire thru your State consumer body and/or the ACCC. Just the mention of 'consumer afairs complaint' might be enough to get some action from 'Engel'.

The specification sheet nominates the compressor voltage at 13-16vAC.
The current I am measuring is 20-21v AC.
The compressor cuts in and out at intervals of 2 or 3 seconds.
I am wondering if the circuit board (there is two boards opposite each other, 1 to change 240 AC to 12v DC and the other board does the rest) is heating up on of the components and causing the current to switch on and off. thanks guys for your input. You have been more informative than 3 agents I have approached.

Mezza I would be looking at the compressor Drive board for the fault, would be interesting to see a pic of the board. DeBe

Could be, but these fridges usually run continuously without refrigerant, there's no low-pressure cut-out installed to stop them when the refrigerant leaks out. Reverse polarity is quite detrimental to Engels, not sure of other brands, I have a fridgie mate who works on Waeco's, so I give him any Waeco's to work on, and I get the Engels. I haven't ever worked on any other brands of car fridge.....

Cheers

Brian

That seems to be an odd system? I do a fair bit of refridge work though never touched an Engel.
So without a low pressure cutout what stops the compressor when the box is down to temperature? Normally the thermostat will shut off the solenoid at temp, then the compressor pumps down and stops when the suction pressure around +1psi and LP cuts out.
If the compressor runs "continuously" without refrigerant rather than short cycling then every Engel that loses gas would have a compressor failure also due to no lubrication and sucking into a vacuum wouldnt it?

Sorry not questioning your knowledge but trying to get a handle on how these "iconic" fridges work.
It would seem to be a very crude system if this is the case?

"Normally the thermostat will shut off the solenoid at temp, then the compressor pumps down and stops when the suction pressure around +1psi and LP cuts out.
If the compressor runs "continuously" without refrigerant rather than short cycling then every Engel that loses gas would have a compressor failure also due to no lubrication and sucking into a vacuum wouldnt it? "

100% correct, in a commercial cool room/freezer situation. Also, you can control the fridge temp via a LP control, without a solenoid, by setting the cut-out at a setting that corresponds to the temperature desired in the fridge. (Not for capillary systems, more for tx valve.)

But the most common form of control is a simple thermostat that operates the compressor. No pump down. This is the system that is in most domestic fridges, and also used in the Engel, Waeco and Trailblaza fridges, although in these the thermostat actually operates the compressor via the electronic box. The down side is, as you mentioned, the risk of compressor failure due to overheating with no refrigerant return to cool the windings.

"Sorry not questioning your knowledge but trying to get a handle on how these "iconic" fridges work."

No need to apologize fisho, you had a question and you asked it. And you asked in a way that can't be taken offense at.

"It would seem to be a very crude system if this is the case?"

Crude, yes but popular. Keeps the manufacturers cost down, wall mount split system air cons and window units mostly don't have any safety pressure switches either..... the only one I have ever seen was a Benson unit, that runs R290, which is basically, BBQ gas. (I worked on one, and one only. I will never work on another one!)

Hope this helps....

Cheers

Brian

Forgot to add.....

Without endorsing this as an instruction on how to do it... disconnect the fridge from ALL sources of power. Park it a long way from a power source so you won't be tempted to turn it on while you're in there poking around. Electricity and human flesh do not like each other as friends!!!!!!! Have a good look and you'll see the screws that hold it together, some are underneath so you need to find them all. Gently, remove the screws and thus the panels holding the casing together. Remember.... GENTLY! You shouldn't have to force anything. Once inside the compressor compartment, have a good look at the wiring looms to the electronic box, and from the box to the compressor. If you smelled burning plastic, you will see the damaged wiring. It may just be that the wiring is burnt and needs replacing, which will be a cheaper job. However, experience tells me that there will be damage to the board too, and you possibly will be able to see the damage there as well.

Cheers


Brian

Thanks guys
I have had power box apart and the only visible problem to the untrained eye is the black wire (I am assuming its the earth) going from the 12v dc input plug to the board shows signs of heating up. There are 4 components around the 12 input which I don't know the name of (the are not diodes) which look for want of a better description like black cylinders connected to each other in pairs (making a total of 8 cylinders) They connect between different parts of thr printed circuit. These cylinders look like they have a drop of glue where the wire comes out the top. Does anyone know what they are, what they do and should they look like this? mezza

Hi
I have taken some earlier advise and posted pictures on the Grey Nomads site under Techies corner. Hope this explains some of the circuitry but if you need more I will try to help. thanks guys - mezza

Hi Mezza, The black cylinders are L7 &L8 are just loops of single strand wire with 2 ferite beads on them, they should be ok if not blown, easy to repair if there is no continuity through them just use a piece of wire same thiknes through the beads. The large diodes one marked ZD4 Zenner diode Check neither diode is shorted, Solder joint betwean diodes looks iffy been hot. Check solder joints on other side of board with good magnifying glass for poor solder joints. Will PM you on GN. Daryl

Had a technician check diodes and loops - telis me they are OK - one solder doesn't look flash - will resolder and try it again - thanks mezza

resoldered joint - made no difference - still switches off and on at 3-4 seconds intervals. at a loss where to go from here - mezza

Mezza,
Might be a silly question, but have you replaced the burnt wire? If that is now a high resistance wire, your compressor won't operate correctly.


Cheers

Brian

Not a silly question because I haven't. but wouldn't that only come into play when the fridge is running on 12v DC? Mezza

Sorry, I misunderstood and thought it was the wiring from the board to the compressor that was burnt.

Another check to try, and do this VERY carefully, when the compressor cycles on, how much voltage is at the terminals of the compressor? If initially it has correct voltage, but "drags down" on the meter, there is an output problem somewhere. Burnt terminals/wiring can do this.

Not sure where you would go from here if that doesn't give results.

I'll give it some thought and post if I think of anything else.

Cheers

Brian

Hi guys
Have checked the voltage at connecting plug between power supply and compressor - reads between 20-21v AC but then switches off and on at about 2-3 sec intervals. Something is cutting the circuitry in and out maybe because it is to high, don't know - thanks mezza

Sunday - Been to a friend who is a former electronic technician. Checked lots of components and can't find anything shorted. Out of curiousity disconnected 240 input board and tried running the fridge from a battery through just the 12v board. This makes the fridge compressor run "normally" without the constant cutting in and out. After 15-20 minutes the fridge temperature was not altering. Is there some way of checking if the gas has leaked out? Or what else could be wrong? The voltage at the plug going to the compressor is reading 12.5V AC (this may be too low - the specification sheet says 13-16V).
Thanks mezza

Mezza,

Are you certain the compressor was running? Can I ask how you know that the compressor was running?

They don't have a service port for checking the refrigerant level. But after 20 minutes the condenser (the black piping around the compressor compartment) should be warm/hot and the evaporator inside the fridge should be getting cold. Where the evaporator (the bit inside the fridge that does the cooling) piping enters the fridge, there should be a frost line, wetting your finger with your tongue and then touching the evaporator should cause your finger to lightly "stick" to the plate.

If it cooled OK before the wiring fault, and now doesn't, I'd be surprised at the coincidence of a leak at the same time, unless you have broken a pipe in the fault finding process. Or is there a kinked pipe? (Not having a go at you, it's very easily done.) If there is no chance of either of the above, then I'd say that there is still an electrical issue.

Cheers

Brian

Thanks Brian - the fridge makes areasonable amount of noise when the compressor is running so I am assuming it is working OK. I have touched any pipes yet but the fridge makes a strong vibrating noise which is the condenser setting up a vibration at the extremity. I think this is a design fault as it doesn't have any packing or mounting near the end of the condenser. I have the intention of putting someting between the condenser and the casing shell if and when I get it running properly. I have wondered if maybe the condener piping has developed a crack because of the vibration which at times becomes quite audible. What do you think? Mezza

There is a possibility that the piping is cracked, but the only way to know is to pressure test. Without actually being there, I am kinda out of ideas at the moment Mezza..... If I can think of anything else, I'll get back to you.

Cheers

Brian

Thanks Brian - Do you think it is possible that with what I did to the circuit boards that the current could be reversed and the compressor is running in reverse? Oh for a circuit diagram! Changed the black wire which was scorched with no noticeable difference. thanks mezza

These fridges dont have a motor, The piston is driven by a solenoide so there is realy only one moving part. Daryl

Thanks Daryl - guess that rules out wrong polarity - looking more and more likely that gas line has fractured somewhere. Great. Will have to try and find a fridge man to check it out. thanks mezza