Euretic Plates - Some Plates not cooling at all but compressor is fine.

[Potia71]

I need help and advise from anyone who is familiar with a Eutectic plate refrigeration system.

I have 3 refrigerate trucks, all with eutectic plates. The problem is, on first purchase, they worked fine but after a few months, each started having issues.

The problems started gradually.

I have a Mercedes Eutectic plate refrigeration system with stainless steel plates which works like fire, but recently, I noticed one side, quite close to the edge no longer freezes on all the plates along that side.

Then I have 2 IVecos with metal plates Eutectic; Now, one is a Eurocargo and the other is a small truck. The problems are identical. The eurocargo has about 6 plates in total, but 3 works, 3 dont cool at all. The 3 that works, only one cools very well and quite quickly. But when I first bought it, it was super. The smaller Iveco, same issue, out of 5 plates, oly 2 works, the other 3 has no cooling.

Now, on this aspect, I am not very knowledgeable and technical but I would appreciate any advise given simply and clearly. We have cleaned the condenser for the Eurocargo and that did help with the 3 plates that cools quite abit. Especailly, with the one that cools fast.

We have also tried adding gas, but that don't seem to be the issue. We are struggling to find a qualified engineer to truly check this out due to where we are. Its hampering the usual.

Some people say its chemical in the plates, I feel its just water which might need replenishing. Simplistic, I know. But I truly dont know much at all about this plates and their maintenance.

Please help anyone.

[seanf]

I wouldnt think it would be just water.

Are the plates connected on the refrigeration system in series with each other or does each one have its own inlet / expansion valve?

What gas are the systems running on?

Do you have running pressures for the high and low side of the systems?

Do the refrigeration systems have a liquid line sight glass? for looking at the flow of the refrigerant.

If you say roughly where you are, someone might give a suggestion on who to try.

[NH3LVR]

I have some experience with Eutectic Plates and designed and installed a system once.
I can assure you that they are not filled with water.
Please answer Seanf's question and include any details you can.
Strange that they are all misbehaving. Perhaps someone who does not understand them has changed something.
Are the Plates marked with a Eutectic point? Are the compressors cycling.?

[Potia71]

I wouldnt think it would be just water.

Are the plates connected on the refrigeration system in series with each other or does each one have its own inlet / expansion valve?

What gas are the systems running on?

Do you have running pressures for the high and low side of the systems?

Do the refrigeration systems have a liquid line sight glass? for looking at the flow of the refrigerant.

If you say roughly where you are, someone might give a suggestion on who to try.

Thank you for taking the time to even reply. I truly know nothing about this Eutectic plates an their maintenance. The cooling systems with a blower and evaporators, are much more easier for local engineers to repair, but none seem to have a clue on these Eutectic systems.

I am going to ask someone later on today about some of your question and maybe get some photographs to see if it might help to understand it.


The only question I can answer right now is that, the plates are connected in series to each other and not individual outlet that I can see or expansion valve.

I will check out some of the info in a couple of hours and be back on here. The vehicle of worry if an Iveco Eurocargo 75E18.

I purchased it in a couple of years back to the day, from Belgium. The vehicle is in a small town in Mauritius - Tamarin.

The vehicles have not really been touched at all. The only issues they had was with the Eurocargo, the compressor got burnt after about 12 months of use, and It was "rewind". Then it was noticed it wasn't done properly, and it was repeated again in about 2 months.
And to be honest, the cooling system was not as cold after that point but the plates were working then.

Slowing, I noticed those two plates were not working well, and then a third. And now they almost don't work at all.

The mercedes and smaller iveco, has not been touched at all in anyway.

I actually do prefer Eutectic plates refrigeration because of the way they cool and retains the coolness, but with 3 vehicles having a similar issue, I am just not keen on purchasing such a type of refrigeration again.

[Potia71]

Thanks for your prompt response.

As I replied to seanf, I have no clue about this Eutectic refrigeration system at all. I am not a engineer. I did get someone to open the valve on one of the plates that wasn't working, because I assumed it might be like the home heating system, where it just needs bleeding. When we opened it, abit of water came out. So I just believe it might be filled with water.

Plus we had an old iveco truck bought locally that the plates were rusted some years old. We changed the system to the blower and evaporator which local people have knowledge of. We cut the plates out and drained them before they were sold, and I thought the liquid that came out was just water but no one else agreed.
Beyond the Compressor being rewind for the Eurocargo, nothing has been changed.
And yes, its strange to truly have 3 vehicles with the same issues.

[Potia71]

I have some further information, I am told the gas it uses is 404. I hope that is some kind of standard type gas. This is for the Eurocargo. But i'm told all the vehicles uses the same. But we've not had to put gas in the other trucks.

I noticed something however, whilst recording. We plugged the Eurocargo in overnight from last night just to see how good or worst the situation has become. And you can see from the video, only 3 plates are well frosted after 13 hours.

But I noticed the pipes connecting the plates, are frosted, for the plates that properly iced. But the plates that are not frosted, the pipe going into them are not even cold at all, but the second pipe from them linking the main pipes is quite cold but not frosted. So I'm just wondering if this is where the problem lies. And how is it that, the plates that aren't working are spread between the working ones.

As regards your question about low and high running pressures. For now I do not honestly know what that means but am researching it to know more.

Then with regards to the liquid line sight glass, I didn't see anything of such but u can have a look at the vide and see if there's anything that is helpful.
https://youtu.be/nlb_6-IcWec
I also did a Recording for the Mercedes Sprinter. But it wasnt plugged in. Along the edge where the pipes are, are the areas thant don't get frosted at all. It like 2 inch from the edge of each plate on the pipe side of the plates. Other than that the sSprinter works like a dream. https://youtu.be/nlb_6-IcWec

[frank]

At 20 seconds into your video, the sight glass is flashing, suggesting that you have a shortage of refrigerant, possibly due to a leak somewhere.

[seanf]

Hi Potia71,

See links to pictures.

https://www.flickr.com/photos/s34n/5...posted-public/

No. 1 is the liquid line sight glass.
No. 2 is the liquid line filter drier.
No. 3 looks to be the liquid line solenoid valve.
No. 4 is the compressor suction line/pipe.

https://www.flickr.com/photos/s34n/5...posted-public/

No. 5 is an expansion valves buld.
No. 6 is an expansion valve.

I'm not as sure as frank is about the sight glass flashing (showing gas and liquid refrigerant in the pipe), I think its a bit hard to tell from the video as it could just be reflections in the glass that were seeing.

It would be good to get the running pressures for the high and low sides of the system, along with a video of the refrigerant flow in the sight glass (let the system run for atleast 15 minutes if its not already been running). When your giving the pressures and video include what air temperature the box is at and the outdoor air temperature.

404 gas (R404a) is a standard refrigerant, but I cant say how easily available it is to get in Mauritius. Youd need to ask the locals.

[Potia71]

Thanks again. seanf, I will check out what you pointed to and do another video as soon as the load in the truck is removed, which might be tomorrow. Gas was added again 2 days ago. We can get the gas ok, that is not an issue. And we've added several times but not made any difference.

The sight glass you mentioned, now I will not say its flashing, or would you call that flashing? I thought it was more of a circular motion. And I have asked why the little glass had movement, I cant remember the response but I know it is gas related. And yes while recording it did look like it was flashing. But I will go and observe again as soon as the truck is on. I take it the numbers there will provide further information.

There was something else I noticed, the plates are linked by to one main pipe, but each place is also linked to another plate, so they are like pairs. Now I can see that, its one of each pair that isnt working, which is strange. I don't know why we never noticed this before. And the issue is the same for the other iveco truck. Only the Sprinter's issue is slightly different.

[seanf]

Hi Potia71,

The pictures were just to show you what people on here mean when they say "expansion valve" or "sight glass" or..... as someone may suggest checking different parts in the system.

The running pressures and temperatures can be useful for fault finding, as well as seeing what is happening in the sight glass.

The expansion valve is what feeds the refrigerant into the plates. The large pipe that connects to all of the plates is the return pipe to the compressor.

Is it the plate that has the expansion valve connected to it, the one that is cooling well? And is it the second plate connected in series, the one that is not cooling?

There are a few reasons why the second plate is not cooling.
It could be like frank said, that there isnt enough gas in the system and you have a leak.
It could be that the expansion valve has a blockage in its strainer or that the valve is faulty.
It could be that the expansion valve is not set up correctly.
It could be something else, but its hard to tell without looking at the pressures and temperatures.

[Potia71]

Hi everyone,

Due to work commitment over the weekend which is our busiest time, I could get a minute to respond back.

I dont know if these figures will make sense but when the sight glass goes up what we can see is MWP500psig/1757

And when it goes down what we see is PB35bar/80.cSGN. I ssdont know if those makes sense.

Now I got an alternative possible solution from Cold car whom I believe are the creators of the cooling system. They believe that there might be air and a leak in the system and that we might need to drain or trap the gas, then infused nitrogen to check for any leaks and then afterwards vacuum the system for a while.

Now, how easy this will be, I do not know, but we have to try something because for now, we are desperate.