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TfW 158s air conditioning problems

Andrew888

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Having spoken with an a/c engineer, he doesn't really understand why so many would fail simultaneously (rather than evenly over time)

- system would be used all year because it also does dehumidifying and demisting in winter
- it's not like an engine that can overspeed, it should be able to run continuously at its maximum setting.
- gas won't leak from properly maintained pipes and seals

So is it the air con has just suddenly failed in last week or so, or is the truth that a lot of it it failed months ago, and sloppy maintenance didn't get it repaired many weeks/months ago.
As someone who's travelled the Cambrian line for well over a decade (Mach/BHI), I can tell you the A/C on those units is broken almost all of the time.

If you're lucky, you'll occasionally find a single carriage on a four-car set where it's doing the job, but mostly it just doesn't work.

Maybe you can find a guard to open the windows, and then you have to pray the train keeps moving and doesn't, say, stop for half an hour at the Caersws passing loop for the train coming the other way. But if the train is rammed, and it often is due to TFW running short trains, the guard won't be able to reach you.

The situation over the last week has been absolutely ludicrous. They've suddenly decided to try to fix all the A/C units *now*? In the middle of a heatwave? It's just nonsensical.

It's led to services either being cancelled (typically leading to another two hours travelling in this heat due to the low frequency), or being run with two carriages, hence absolutely rammed, and still with no A/C. They've made a bad situation massively worse.

This heatwave has been relatively mild compared to the last one, where I had one of my most unpleasant rail journeys ever on that line, so again, why now? (And yet they keep posting notices about extreme temperatures while cancelling trains due to unit shortages. 25° is not extreme.)

It's a scandal to be honest. No one in TFW management seems to know what the hell they're doing or what their customers are experiencing. Or care.
 
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Caaardiff

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As someone who's travelled the Cambrian line for well over a decade (Mach/BHI), I can tell you the A/C on those units is broken almost all of the time. If you're lucky you'll occasionally find a single carriage on a four-car set where it's doing the job, but mostly it just doesn't work. Maybe you can find a guard to open the windows, and then you have to pray the train keeps moving and doesn't, say, stop for half an hour at the Caersws passing loop for the train coming the other way. But if the train is rammed, and it often is due to TFW running short trains, the guard won't be able to reach you.

The situation over the last week has been absolutely ludicrous. They've suddenly decided to try to fix all the A/C units *now*? In the middle of a heatwave? It's just nonsensical. It's led to services either being cancelled (typically leading to another two hours travelling in this heat due to the low frequency), or being run with two carriages, hence absolutely rammed, and still with no A/C. They've made a bad situation massively worse.

This heatwave has been relatively mild compared to the last one, where I had one of my most unpleasant rail journeys ever on that line, so again, why now? (And yet they keep posting notices about extreme temperatures while cancelling trains due to unit shortages. 25° is not extreme.)

It's a scandal to be honest. No one in TFW management seems to know what the hell they're doing or what their customers are experiencing. Or care.
25 degrees is not extreme, but it's recently been 33-35 degrees.
As the 158's have aircon fitted, Depots are obliged under maintenance rules to not allow units to leave the Depot with aircon not working. It also takes into account Driver Cab air con.
Carriages have been reaching 35-40 degrees inside. Try driving a train in that temperature. Drivers are (quite rightly) refusing to drive in those conditions, and guards are (quite rightly) refusing to allow passengers to put in those conditions.
 

Snow1964

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25 degrees is not extreme, but it's recently been 33-35 degrees.
As the 158's have aircon fitted, Depots are obliged under maintenance rules to not allow units to leave the Depot with aircon not working. It also takes into account Driver Cab air con.
Carriages have been reaching 35-40 degrees inside. Try driving a train in that temperature. Drivers are (quite rightly) refusing to drive in those conditions, and guards are (quite rightly) refusing to allow passengers to put in those conditions.
But the question is was some of the a/c broken months ago, no one fixed it, and trains were allowed out with it broken.

Should they have refused to accept failed a/c months ago, but didn't so management got lulled into false expectation, due to drivers being inconsistent. Then depots then couldn't cope fixing loads of coaches in just a few days when it warmed up.

Let's be straight, the depot that fixes the a/c is also the one maintaining the brakes and sanders. Unless they have inconsistent quality standards everything should be maintained in working order.
 

Peter Sarf

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But the question is was some of the a/c broken months ago, no one fixed it, and trains were allowed out with it broken.

Should they have refused to accept failed a/c months ago, but didn't so management got lulled into false expectation, due to drivers being inconsistent. Then depots then couldn't cope fixing loads of coaches in just a few days when it warmed up.

Let's be straight, the depot that fixes the a/c is also the one maintaining the brakes and sanders. Unless they have inconsistent quality standards everything should be maintained in working order.
I recall reading (probably on the 197 thread) some months ago that TfW had been short of money and some 197s that had been long term out of use should return to service soon as more mony was now (some months ago) available to buy parts.

So if my memory of above is correct then it follows TfW could have been saving on the cost of some repair work to air-conditioning - either because they did not have the parts OR because they wanted to save on labour costs. Not fixing air-conditioning during the cooler months does leave an operator at risk from a usually rare heatwave.

Mind you air-conditioning not working is a problem I faced in many of my work places. So it is not just trains. A bit off topic but I well remember us working out that the mechanism controlling the flap valves regulating cool vs normal airflow was faulty in many parts of our office. It sounded like a motor driving a worn cog wheel and just jumping. So most of the working day we endured the rasping/grating sound above our heads which occasionally stopped - we believed probably when the room temperature was near enough to correct. One evening we got chairs on desks, moved ceiling tiles and disconnected the power to the noisy things. Next day most people thought the air-conditioning had been repaired. Just be thank full the air-conditioning on trains does not make annoying noises - or do they ? (I do not travel enough these days).
 
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sd0733

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So if my memory of above is correct then it follows TfW could have been saving on the cost of some repair work to air-conditioning - either because they did not have the parts OR because they wanted to save on labour costs. Not fixing air-conditioning during the cooler months does leave an operator at risk from a usually rare heatwave.
Theres been a big programme of Air conditioning system overhauls on the 158s over the winter/spring months. Most units had been done with just a couple outstanding so it certainly isnt that.
Unfortunately the systems fitted to the 158s are just not fit for purpose anymore, with age and increasing use/temperatures, its effectively useless. At this point in the lifespan of the 158s its never going to be cured now but its a huge achiles heel of an otherwise good unit.
 

Peter Sarf

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Theres been a big programme of Air conditioning system overhauls on the 158s over the winter/spring months. Most units had been done with just a couple outstanding so it certainly isnt that.
Unfortunately the systems fitted to the 158s are just not fit for purpose anymore, with age and increasing use/temperatures, its effectively useless. At this point in the lifespan of the 158s its never going to be cured now but its a huge achiles heel of an otherwise good unit.
That's a thought. It is very true that the 158s are from an older era so to speak. To compound things now with their imminent (theoretically) replacement by 197s no one can justify any upgrades to these 158s !.
 

Harpo

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That's a thought. It is very true that the 158s are from an older era so to speak. To compound things now with their imminent (theoretically) replacement by 197s no one can justify any upgrades to these 158s !.
158s also have very limited headroom electrically. ETCS needed 2kw, which was available at the time but earmarked for cab air-con, so a major power saving scheme had to be paid for before installing ETCS. Passenger power sockets probably took any residual power?
 

Snow1964

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That's a thought. It is very true that the 158s are from an older era so to speak. To compound things now with their imminent (theoretically) replacement by 197s no one can justify any upgrades to these 158s !.
Tfw might not think it is justified if they are in last year or two of them using them, but it becomes a problem for lease company or any operator that takes them for few years further use.

If someone else wants them for about 5-7 years, will they take them knowing the a/c system needs upgrading, unless upgrade is done.
 

Peter Sarf

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158s also have very limited headroom electrically. ETCS needed 2kw, which was available at the time but earmarked for cab air-con, so a major power saving scheme had to be paid for before installing ETCS. Passenger power sockets probably took any residual power?
So there is a chance these 158s air-conditioning could work a bit better once they are off an ETCS route.
Tfw might not think it is justified if they are in last year or two of them using them, but it becomes a problem for lease company or any operator that takes them for few years further use.

If someone else wants them for about 5-7 years, will they take them knowing the a/c system needs upgrading, unless upgrade is done.
I agree. It risks shortening the 158s useful lives. TfW cannot be expected to upgrade them, so it will be the responsibility of the ROSCO (Rolling Stock Company) or the next user. So, unless the next user plans to keep them for long enough, these 158s won't get any significant upgrades.
 

Harpo

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So there is a chance these 158s air-conditioning could work a bit better once they are off an ETCS route.
My understanding is that the existing air con system is (technical term) crap, so is probably unaffected by having ETCS on board.

If the 158 after-life is minus ETCS (which would be ironic), I’d guess 2kw extra ain’t going to make much difference?
 

Richard Scott

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My understanding is that the existing air con system is (technical term) crap, so is probably unaffected by having ETCS on board.

If the 158 after-life is minus ETCS (which would be ironic), I’d guess 2kw extra ain’t going to make much difference?
2kW is about 3hp so insignificant, probably there's at least that much of a difference between two different engines? Doubt passenger sockets make any noticeable difference as limited to 150W per socket. 5 sockets running at full load is 1hp! It's a bit like old argument that people had about 47/8s were more unreliable because of extra weight of the fuel!!
158s have had air conditioning issues for as long as I remember and never really been solved.
 

Richard Scott

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In terms of crankshaft horsepower yes, but if it is 2kW more than the alternator will produce, it is more than enough to shut it down on overload, overheat it or cause flat batteries.
Quite possibly, then needs an upgraded alternator fitted but be surprised if the originals are running so close to rated spec without the additional load. I'm sure someone has thought of that?
 

Harpo

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Quite possibly, then needs an upgraded alternator fitted but be surprised if the originals are running so close to rated spec without the additional load. I'm sure someone has thought of that?
It would be interesting to know if the ETCS project was offered an upgraded alternator instead of the load shedding that was opted for to get the required headroom.
 

Russel

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The situation over the last week has been absolutely ludicrous. They've suddenly decided to try to fix all the A/C units *now*? In the middle of a heatwave? It's just nonsensical.

I agree, it does seem a strange move, butcher the service to "fix" air-con that hasn't worked properly in 20 years?

What makes it even stranger is there is fleets of 150s, 156s and even other 158s across the country that are just going about their daily duties...
 

Cardiff123

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If the 158s are to have any future after TfW, I think at this point it would be easier to permanently disable the faulty air con in 158s, and re-fit all of the windows with opening hopper windows.

Not ideal, but better than having a unit with sealed windows and no air con during increasingly hot summers.
 
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Ashley Hill

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I don’t know the situation with TfW but at my TOC guards used to be able to access the AirCon control panel (not any more). The EBAC AirCon units could be overridden (with 75% success) to full cooling. The Temperature units were a bit more temperamental and were (are) less reliable.
 

Andrew888

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25 degrees is not extreme, but it's recently been 33-35 degrees.
As the 158's have aircon fitted, Depots are obliged under maintenance rules to not allow units to leave the Depot with aircon not working. It also takes into account Driver Cab air con.
Carriages have been reaching 35-40 degrees inside. Try driving a train in that temperature. Drivers are (quite rightly) refusing to drive in those conditions, and guards are (quite rightly) refusing to allow passengers to put in those conditions.
What you say sounds reasonable. But I've been in those 40°+ conditions inside multiple times (I take this route at least several times a month), so I'm sceptical about guards refusing to put passengers in those conditions. I'm not sure I'd want them to given at the end of the day I need to get somewhere and there aren't always a lot of options.

Anyway. My point was that running fewer services with a smaller number of carriages that still don't have A/C (as per my last trip) doesn't make things better for the passenger, no matter how many cans of warm water you hand out. It would've been better to make the trip in two less hours in a four-carriage train that wasn't rammed with body heat further contributing to the issue.

Sure, fix the A/C if possible, but perhaps do it after the next heatwave. And I can't square units not being allowed to leave the depot without air con working with my experiences over the years. Perhaps this a new rule with some unintended consequences? In 13 years I can remember two (2) occasions in which the A/C worked in those carriages. Admittedly only really detectable when it's 25°+.

Maybe the drivers are indeed the concern. Though presumably at least they have control over their windows :D

If the 158s are to have any future after TfW, I think at this point it would be easier to permanently disable the faulty air con in 158s, and re-fit all of the windows with opening hopper windows.

Not ideal, but better than having a unit with sealed windows and no air con during increasingly hot summers.
Amen! Perfect being the enemy of good etc.
 

tomoufc

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I agree, it does seem a strange move, butcher the service to "fix" air-con that hasn't worked properly in 20 years?

What makes it even stranger is there is fleets of 150s, 156s and even other 158s across the country that are just going about their daily duties...
The country?
 

Peter Sarf

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Well, I wasn't referring to the Thai 158s...
Now..... Since you mention them I well remember seeing the Thai 158s buzzing around with (all ?) doors open !. No need for aircon there then !.

I took "across the country" to loosely mean the UK/GB.

And hopper windows do seem to have a very very low failure rate.
 

Russel

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Now..... Since you mention them I well remember seeing the Thai 158s buzzing around with (all ?) doors open !. No need for aircon there then !.

I've watched a couple of YouTube videos about them, they may be similar to our 158s but totally unrecognizable from a health and safety point of view!
 

Rhydgaled

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TfW could have been saving on the cost of some repair work to air-conditioning - either because they did not have the parts OR because they wanted to save on labour costs.
Apparently, some of the TfW class 158s are due a C6 but TfW don't want to pay for it - I've read that one or two have already been withdrawn as a result. Others are supposedly getting close to running out of mileage/hours and are being used as little as possible to try and keep them going without getting to the point where the C6 is required. I'm unable to verify any of that - can anyone confirm it or prove otherwise? - but if it's true then TfW not wanting to spend money on the 158s sounds plausible to me. Not only that, but if it's the case then TfW seem to think the 197s are going to be super-reliable; enough to introduce yet more services (eg. to Bristol) with a smaller fleet (today's fleet plus the 8th Mark 4 set, minus all their 158s). If you ask me that's utter madness and they should either drop their Bristol plans (along with other such expansion) for the time being or extend the lease on the 158s to provide a larger total fleet (once HD08 arrives and all 77 class 197s are fully-deployed).

Tfw might not think it is justified if they are in last year or two of them using them, but it becomes a problem for lease company or any operator that takes them for few years further use.

If someone else wants them for about 5-7 years, will they take them knowing the a/c system needs upgrading, unless upgrade is done.
This is far from being a new issue, or even a TfW/ATW issue. The class 158 air-con is notorious for being unreliable, across multiple operators. Years ago, on a hot day when I was supposed to be going to my Grandfather's funeral, I was boarding a Portsmouth-bound First Great Western class 158 (probably a 3-car 'hybrid' set, as almost all of them were at the time if I recall correctly) in Cardiff Central and noticed that most of the hopper windows were open. As a result, I made sure to sit in the one and only coach where the windows were closed, on the assumption that the air-con was actually working in there. To my dismay, the guard came through almost immediately and opened them; no air-con on this train then.

Carriages have been reaching 35-40 degrees inside. Try driving a train in that temperature. Drivers are (quite rightly) refusing to drive in those conditions
I'm sceptical about guards refusing to put passengers in those conditions. I'm not sure I'd want them to given at the end of the day I need to get somewhere and there aren't always a lot of options.
As it happens, I never made it to the funeral. Before long we were running late and ultimately the service was terminated at Westbury. My understanding at the time (or forum discussions following the event) was that the driver and/or guard had refused to take the train any further due to the heat. In the end, my family (over the phone, I assume) that there was no point me trying to continue my journey towards Portsmouth on a following service - I was already running too far behind schedule - and I caught the next service (which I think happened to be a 150) back to Bristol Temple Meads. I think I had my first sighting of 43172 in it's remembrance livery while waiting there for a train back to Wales.

It would've been better to make the trip in two less hours in a four-carriage train that wasn't rammed with body heat further contributing to the issue.
158s also have very limited headroom electrically. ETCS needed 2kw, which was available at the time but earmarked for cab air-con, so a major power saving scheme had to be paid for before installing ETCS. Passenger power sockets probably took any residual power?
One of the many points that comes up from time-to-time in forum discussions like this is that the class 158's air-con system is unable to overcome passenger body heat. I forget whether the carriage has to be crush-loaded for that to be the case or, if not, how many seats have to be occupied before it's a problem (anyone know what the rating of the air-conditioning is and how many kW of heat the average human radiates?). However, because of this the guards open the hopper windows and then the air-con has to try and cool the whole planet and packs up completely. Again; that's just what I've read in the past and I cannot be sure if it's accurate.

2kW is about 3hp so insignificant, probably there's at least that much of a difference between two different engines? Doubt passenger sockets make any noticeable difference as limited to 150W per socket. 5 sockets running at full load is 1hp! It's a bit like old argument that people had about 47/8s were more unreliable because of extra weight of the fuel!
It's my understanding that all the TfW class 158s are fitted with 350hp Perkins engines, and that the only two other engine types across the entire BR class 158/159 build are a 350hp Cummins design and a 400hp Cummins engine. The latter is only found on the class 159/0 3-car units and a small batch of 2-car class 158s which I think are with Northern. The vast majority of class 158s (plus the class 159/1s) are therefore fitted with 350hp engines of one kind or another. If I recall correctly the ATW class 158 refurbishment provided 3-pin power sockets for the table seats only (with airline-style seats being limited to USB sockets) due to limited available electrical power.

Quite possibly, then needs an upgraded alternator fitted but be surprised if the originals are running so close to rated spec without the additional load. I'm sure someone has thought of that?
Interesting thought Richard. However, these are 90mph units - most newer stock has at least a 100mph top-speed and the lesser sprinters are 75mph units so perhaps BR wasn't able to find any more-powerful engines small enough to get under the floor at the time?

I think at this point it would be easier to permanently disable the faulty air con in 158s, and re-fit all of the windows with opening hopper windows.

Not ideal, but better than having a unit with sealed windows and no air con during increasingly hot summers.
I might have been tempted to agree; however when it gets hot there are often speed restrictions in place. On my aforementioned trip to Westbury, the open windows provided a cooling draught only when a decent speed was reached. Most of the time we were crawling along and the open windows offered little or no relief.
 

Caaardiff

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Apparently, some of the TfW class 158s are due a C6 but TfW don't want to pay for it - I've read that one or two have already been withdrawn as a result. Others are supposedly getting close to running out of mileage/hours and are being used as little as possible to try and keep them going without getting to the point where the C6 is required.
Not sure that is true. There are currently 158s on C4 exams which are stuck in a backlog.
No 158s have been withdrawn.

As they still have life in them, its unlikely the leasing company would allow those exams to expire when they are intended to be handed back.
 

Rhydgaled

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Not sure that is true. There are currently 158s on C4 exams which are stuck in a backlog.
No 158s have been withdrawn.
My apologies; I've just double-checked the e-mail I read that in and the wording used was that two TfW 158s were 'stored out of use' (at Cardiff Canton). The word "withdrawn" wasn't actually used (in that context at least).

As they still have life in them, its unlikely the leasing company would allow those exams to expire when they are intended to be handed back.
I seem to remember that some of the class 91s were run down in a similar way when a major exam and/or overhaul was due. Then when the lease ended up being extended some of the overhauls/exams were done (possibly around 91119 getting Swallow livery?). So, I didn't think the TfW class 158 situation was all that strange (even assuming my information was accurate), just that it implies that TfW are still intending to withdraw their 158s despite talk of introducing Bristol services.
 

Richard Scott

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It's my understanding that all the TfW class 158s are fitted with 350hp Perkins engines, and that the only two other engine types across the entire BR class 158/159 build are a 350hp Cummins design and a 400hp Cummins engine. The latter is only found on the class 159/0 3-car units and a small batch of 2-car class 158s which I think are with Northern. The vast majority of class 158s (plus the class 159/1s) are therefore fitted with 350hp engines of one kind or another. If I recall correctly the ATW class 158 refurbishment provided 3-pin power sockets for the table seats only (with airline-style seats being limited to USB sockets) due to limited available electrical power.


Interesting thought Richard. However, these are 90mph units - most newer stock has at least a 100mph top-speed and the lesser sprinters are 75mph units so perhaps BR wasn't able to find any more-powerful engines small enough to get under the floor at the time?
Engine power isn't the issue it's the alternator supplying the electrical side that possibly needs uprating. This will put a larger parasitic load on the engine leaving less available for traction but the amounts we are talking about here are miniscule and doubt it would be noticed or affect train schedules. Not like a class 31/4, which was reputed to be able to heat more coaches than it could haul!!!
 

Clarence Yard

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Nothing wrong with the haulage capacity of a class 31 - but stopping it with a large load was another matter!
 

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