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Why did the class 175s set themselves on fire in 2023?

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JulienD

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With the 175s going to GWR, let's hope we don't have a repeat of the problem that caused the 175s to randomly light on fire.
 
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Malkemy

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In addition to looking ugly, they also spontaneously combusted? What a weird class of rolling stock. Alstom had one massive brain fart with the Coradia 1000 series.
 

JulienD

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In addition to looking ugly, they also spontaneously combusted? What a weird class of rolling stock. Alstom had one massive brain fart with the Coradia 1000 series.
3/3/2023
More than 100 services have been cancelled across Wales after trains were withdrawn for safety checks following a number of fires.

The shortage of available trains will mean disruption into early next week, Transport for Wales (TfW) said.

The work was prompted by three "mechanical failures" which caused fires on Class 175 trains.
Source: BBC news https://www.bbc.co.uk/news/uk-wales-64834688
 

BillStampy

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In addition to looking ugly, they also spontaneously combusted? What a weird class of rolling stock. Alstom had one massive brain fart with the Coradia 1000 series.
It wasn't really the fault of Alstom, as far as I know the main player in the thermal events of 2023 was CAF. As the 175s were in their last year at TfW and the 197s required maintenance from CAF, Chester depot was given to CAF and they covered the maintenance of both fleets. Clearly they didn't do as good a job as Alstom as the aforementioned fires took place. Considering Laira has Alstom to help them out I'm sure the units will not have repeats of these thermal events if they maintain them correctly.

As a personal thing, I actually quite like the look of them, it fits a regional train and I think they'll do great in Devon and Cornwall as that role, especially when paired up into 4/5 coach formations.
 

The Prisoner

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The issues with the maintenance have been discussed over and over. CAF didn’t maintain them properly which led to the fires. When Alstom maintained them there were few issues.

There needs to be a responsibility for members not to post speculation like this. A potential customer might read this thread and assume all class 175s are powder keg infernos ready to spontaneously combust at any moment mid journey. Clean them properly to prevent a build of of debris (which GWR and Alstom will do) and there is no risk.
 

XFeed

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Without going into detail not all of the thermal incidents were caused by the same issue, some were a combination of factors.
 
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It wasn't really the fault of Alstom, as far as I know the main player in the thermal events of 2023 was CAF. As the 175s were in their last year at TfW and the 197s required maintenance from CAF, Chester depot was given to CAF and they covered the maintenance of both fleets. Clearly they didn't do as good a job as Alstom as the aforementioned fires took place. Considering Laira has Alstom to help them out I'm sure the units will not have repeats of these thermal events if they maintain them correctly.

As a personal thing, I actually quite like the look of them, it fits a regional train and I think they'll do great in Devon and Cornwall as that role, especially when paired up into 4/5 coach formations.
This is correct. Chester depot transferred from Alstom to CAF in June 2022, a few months prior to the 197s entering service. From what I've heard, the 175s have a tendency to accumulate leaf litter and other debris in their undercarriage. Naturally, with the engines and other hot components located in the undercarriage, if enough debris builds up, it's quite easy for it to ignite. Alstom had implemented a cleaning regime to make sure they never got to that stage while they were in charge of the 175's maintenance - it is rumoured (though not confirmed AFAIK) that CAF didn't carry this regime forward (or at the very least significantly cut down on it) which resulted in these fires taking place in quick succession of each other in early 2023, which in turn necessitated the entire 175 being pulled from service in order to have their undercarriages cleaned to prevent any further fires, before returning to service. I'd be very surprised if Laira weren't very much aware of this and put in place their own cleaning regime as Chester had prior to CAF's takeover.
 

rmHawk765

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Unlike the 180s their diesel hydraulic transmission doesn't just catch fire, because they're not constantly being thrashed at their top speed. They're really not bad units.

Even so, the reliability of the 180s has gone a very long way from the FGW days.
 

tfw756rider

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Wales (sometimes in England), thanks for replying!
Maybe @XFeed could confirm, as they've provided great information about trains that have been maintained at Chester depot (especially the 175s),

but another member of this site (I can't remember who) has said more than once that the underframe wash was programmed to work specifically for the 175s in terms of sensitive areas or something like that,

but then when the 197s started to come in, that was no longer the case, and the 175s just got the same underframe wash as the 197s?

Happy to be corrected if I didn't quite get that right.
 

Tetragon213

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Unlike the 180s their diesel hydraulic transmission doesn't just catch fire, because they're not constantly being thrashed at their top speed. They're really not bad units.

Even so, the reliability of the 180s has gone a very long way from the FGW days.
Sadly, the reputation of those units is firmly down the toilet. "You'll be going nowhere" is probably the most well known thing about them.
 

XFeed

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Chester
Maybe @XFeed could confirm, as they've provided great information about trains that have been maintained at Chester depot (especially the 175s),

but another member of this site (I can't remember who) has said more than once that the underframe wash was programmed to work specifically for the 175s in terms of sensitive areas or something like that,

but then when the 197s started to come in, that was no longer the case, and the 175s just got the same underframe wash as the 197s?

Happy to be corrected if I didn't quite get that right.

Initially the underframe wash for the 175s caused regular "Earth Faults" on the units during its wash cycle. To combat this the wash was subsequently reprogrammed to avoid sensitive areas of the underframe along with the wash pressure being reduced.

I`m unsure whether the wash was ever set up for 197s
 

simonmpoulton

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The units are fine for over 20 years with only the odd issue. CAF get a hold of them and you get many many fires in a short period of time = it's pretty obvious from simple logic who is to blame for that and it's got absolutely nothing to do with the units themselves!
 
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