Class 185 air con issues

[Bletchleyite]

As someone who has years of experience using 185s, I can safely say failing air con is not a new issue at all. They're probably second behind the 158s if I'm honest. It's never aided by traincrew insisting on leaving saloon end doors open to try and circulate air across carriages, which simply makes the aircon on the neighbouring vehicle work even harder to minimal effect on the next carriage.

Yet the 350 aircon is very reliable. Same units, no?

I think, ultimately, you're asking a lot for a diesel engine to drive an aircon unit of the size required. EMUs seem to have issues far less often, I suspect due to the readily available, consistent supply of electricity.

These things have roughly twice the engine power of other comparable 100mph units (i.e. Turbostars). I don't think this should really be an issue at all.

 

[Llama]

This just sounds like an overly complicated system that was obviously going to cause problems.

The issue I was told was poor quality plumbing of said pipes causing coolant leaks into the saloon.

I'm fairly sure there wouldn't be actual underfloor heating on 195s. If there is, it's unnecessary by testament that the HVAC saloon low-level coolant circuits have been largely isolated/drained pretty much since new and there aren't reports of poor saloon heating.

The cab heaters weren't effective enough when it got really cold last winter though, but they're not coolant/waste engine heat related - there's an electric fan heater which emits warm air from the lower desk panels and the cab HVAC will pump out warm air just as the saloon HVAC can do. Even putting on the demister for the radiated heat that provides made an improvement to the cab temperature when it was really cold.

 

[driverd]

Yet the 350 aircon is very reliable. Same units, no?

...These things have roughly twice the engine power of other comparable 100mph units (i.e. Turbostars). I don't think this should really be an issue at all.

I never worked 350s so I can't really comment - I'm just comparing to other units I have worked, as a rule of thumb, EMUs are relatively reliable in terms of the auxiliaries vs DMUs, although I'm sure there will be exceptions too.

170s aircon isn't brill either, they just seem more reliable than 185s, in my experience. It's certainly not rooted in any known fact that EMUs have more reliable aircon, just personal experience and a rough idea of how the system works. In the summer, you're asking an engine that's already working hard and often battling to cool itself (which requires further use of engine power) to then drive a hefty air con system in addition. EMUs, conversely, are only limited by the power available in the grid. As I say, it's a suspicion, not a fact - more than happy to be corrected!

 

[Llama]

Judging by the frequent alternator faults on 195s I'd say that's a pretty reasonable observation.

 

[ic31420]

I suppose an emu generally vibrates less, has a smoother power supply and perhaps, in general, run over better track that doesn't rock and bash them about as much.

 

[Llama]

Not sure that's necessarily the case for 331s which bang and crash about due to the poor ride even on decent track.