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Air conditioning on London Buses

Magrar

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There's definitely something fishy about the whole "Roastmaster" nonsense.

No less than five prototype vehicles ran for thousands of miles in service before full production commenced, so you would assume that if there really was a basic design flaw which meant an underpowered air recirculation system couldn't prevent a stifling build up of hot air upstairs, it would have been noticed.

Or amusingly, perhaps designers/engineers advising delaying the project until a fix could be designed, were indeed overuled. Not by Boris directly, but from the indirect pressure that would come from Boris having to delay their entry into service, inviting mockery and derision from the learned Opposition politicians.

The fitting of opening windows was clearly not the right solution, especially not for a bus that was specifically designed for mid-life upgrades as and when technology allowed. But one does suspect it was the cheapest and quickest, the one most likely to just shut people up and yet again, invite the least mockery of Boris.

Of course, if you did want to fit air-con on them now, you also have to remove (or seal) these fancy new high tech window openings. A bulk order of superglue, perhaps?

Something London's endless parade of brand new buses used for only 5 or 7 years and then tossed to some far flung outpost, usually after an expensive de-Londonification process, don't really need to be designed for. Even though taking out the middle door mid-life is surely one of the stupidest things you'd ever want to do to a vehicle where a lot of structural integrity comes from the body.

Sadly even ten years ago, when it was finally announced windows would be retrofitted, our journalists were too lazy or biased to apply any critical thought and investigate such things for the public interest, and instead just happily parroted Tweets from randoms, or worse, the self serving words of clueless politicians.

It's actually beyond stupid that in the 21st century, our only options seem to be running a bus like it's the 1920s or the 2070s. The reality is it is neither, and so even on an electric bus charged with 100% renewables, air-con comes with a price. A heavier and more complex vehicle. Tyre wear alone will have a huge financial and environmental impact.

As with the double door problem, London can have whatever nice things it wants. They just have to pay for it. In full. Manufacturers won't add it for free. Engineers won't work extra hours for free. Depots won't magically build their own air con fluid handling systems. Second hand users won't remove it for free.

What Londoners can't have it seems, is a bus designed for London, intended to be used for its whole life in London. How ironic to think then, that is probably the most cost efficient way to ensure London can have a bus fleet with air conditioning as standard, but in a way that reduces the extra costs (financial and environmental, upfront and whole life) to an absolute minimum, and in recognition of the fact London will still be a temperate city, climate change or no climate change.
 
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BuhSnarf

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Is there a guide explaining the buses that have air con and those that do not?
Not that I'm aware of, it would be hard to do as different buses have different specs so the same models may or may not have AC depending on how they were bought.

Also, depending on the operator you not always have the same buses allocated to the same routes.
 

Goldfish62

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Is there a guide explaining the buses that have air con and those that do not?
Looking at manufacturers specifications they all claim to have climate control / aircon, but in practice this can be very different things.

The only consistent guide is the TfL vehicle spec, which states that both decks must have an HVAC system which regulates the interior temperature and the ranges at which it must be set in relation to the exterior temperature. Wrightbus somehow managed to gain an exemption to this for their first generation Electroliners, having no aircon system on the Lowe deck (or at all in the Kite), but this has been rectified with the second generation models.
 

Goldfish62

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Something London's endless parade of brand new buses used for only 5 or 7 years and then tossed to some far flung outpost, usually after an expensive de-Londonification process, don't really need to be designed for.
Given that the average TfL bus fleet age is around 8 years buses are clearly not usually disposed of after 5 to 7 years. Not sure where you got that idea from.
 

TheGrandWazoo

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It quite possibly was. The extra weight of proper aircon could well have made its fitment impossible. Double deckers tend to be three axle in mainland Europe to take account of this weight.
Not counting the extra staircase that also adds weight!

Given that the average TfL bus fleet age is around 8 years buses are clearly not usually disposed of after 5 to 7 years. Not sure where you got that idea from.
Quite. It was more the case perhaps 20 years ago or more where you'd have operators cascading vehicles from London into provincial fleets at relatively tender ages (notably Stagecoach) but even then, not exclusively and many were flogged to. Not now where you tend to see vehicles get to 14-16 years old.
 

Thames99

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Not counting the extra staircase that also adds weight!


Quite. It was more the case perhaps 20 years ago or more where you'd have operators cascading vehicles from London into provincial fleets at relatively tender ages (notably Stagecoach) but even then, not exclusively and many were flogged to. Not now where you tend to see vehicles get to 14-16 years old.
Who would want to buy second-hand new Routemasters? They would be a difficult sell to provincial buyers. I imagine they are likely to spend many years in London and thus affect the average life of buses operating in London
 

Snow1964

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Looking at manufacturers specifications they all claim to have climate control / aircon, but in practice this can be very different things.

The only consistent guide is the TfL vehicle spec, which states that both decks must have an HVAC system which regulates the interior temperature and the ranges at which it must be set in relation to the exterior temperature. Wrightbus somehow managed to gain an exemption to this for their first generation Electroliners, having no aircon system on the Lowe deck (or at all in the Kite), but this has been rectified with the second generation models.

There was also a recent FoI answer which stated following at 4 different ambient temperatures. TfL say these are targets (ie do not have to achieve them)
Under the latest issue of the Bus Vehicle Specification, version 2.7, internal temperature setpoint ranges are as follows for the requested external ambient temperatures:
10ºc: 15°C min
20ºc: 17°C-22°C
30ºc: 26°C max
40ºc: No specific target temperature

Clearly a mere 4c reduction at 30c is rather feeble target, and the 11c spread is very wide when most climate systems would be aiming for no more than 2c or 3c variation. It's borderline to being just a token effort at temperature control, rather than a serious system for comfort.
 

Bletchleyite

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There was also a recent FoI answer which stated following at 4 different ambient temperatures. TfL say these are targets (ie do not have to achieve them)


Clearly a mere 4c reduction at 30c is rather feeble target, and the 11c spread is very wide when most climate systems would be aiming for no more than 2c or 3c variation. It's borderline to being just a token effort at temperature control, rather than a serious system for comfort.

I'd be inclined to agree. Maintaining 21 degrees at an air temperature of up to 35 degrees is the sort of specification that is required. 40 is exceptional, but 35 is no longer unusual.

The heating is also inadequate (which would explain why just about every electric bus I've been on has been utterly freezing in winter). 15 is way too low. I get that you go a bit lower in winter because people have coats on for short bus journeys, but it really shouldn't be below about 18-19 or so.
 

TheGrandWazoo

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Who would want to buy second-hand new Routemasters? They would be a difficult sell to provincial buyers. I imagine they are likely to spend many years in London and thus affect the average life of buses operating in London
No one - they couldn't get anyone to buy them in UK or elsewhere. They're owned by TfL (rather than the operators) so they will be in London until such time as they're withdrawn which, given they're coming up to 14 years old, won't be far away. That said, I think the newest are 10 years old. The end of an error...
 

Mikey C

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Not counting the extra staircase that also adds weight!


Quite. It was more the case perhaps 20 years ago or more where you'd have operators cascading vehicles from London into provincial fleets at relatively tender ages (notably Stagecoach) but even then, not exclusively and many were flogged to. Not now where you tend to see vehicles get to 14-16 years old.
And when Stagecoach did that, that was usually with buses with a "compromise" spec, e.g. some of the Volvo Olympians they bought with low height bodywork, which were always planned to be moved out of London.


With the London HVAC system, are the windows meant to be shut or kept open? And is there anything downstairs?

I remember with the Borismaster, that before the opening windows were installed, the HVAC system did a good job at lowering the upstairs humidity, with the windows staying mist free. On one bus where the system wasn't working, it was horribly damp upstairs.
 

Goldfish62

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With the London HVAC system, are the windows meant to be shut or kept open? And is there anything downstairs?
The latest TfL spec requires aircon on both decks and all opening windows to be fitted with locks.
 

SECR263

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On a 196 a few minutes ago from Norwod Jct stand. Went up stairs windows open, shut the lot and temp dropped. Pass got on opened window i said bus was a/c and keep shut. Got off after 5 stops and observed all lower deck windows open. One. Why fit a/c? Two. Do the batteries work like crap to try and cool a bus and shorten battery life and a big bill? . 3 Why are announcements made that bus is a/c and keep windows closed. The Mayor losing a few bonus points to his customers to say new buses Are a/c.
 

Ballyheigue

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On a 196 a few minutes ago from Norwod Jct stand. Went up stairs windows open, shut the lot and temp dropped. Pass got on opened window i said bus was a/c and keep shut. Got off after 5 stops and observed all lower deck windows open. One. Why fit a/c? Two. Do the batteries work like crap to try and cool a bus and shorten battery life and a big bill? . 3 Why are announcements made that bus is a/c and keep windows closed. The Mayor losing a few bonus points to his customers to say new buses Are a/c.
It's an easy one, there are still far too many people with germs flying about so that's probably why windows are open. I'm one of them to be honest but we can't take time off due to strict sickness rules and lack of pay
 

SECR263

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It's an easy one, there are still far too many people with germs flying about so that's probably why windows are open. I'm one of them to be honest but we can't take time off due to strict sickness rules and lack of pay
Has the NHS said there is a problem with Air Bourne infections currently? Is there real medical evidence? Has Khan declared a problem. I would think heat exhaustion is bigger problem for passengers today.
 

Magrar

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Given that the average TfL bus fleet age is around 8 years buses are clearly not usually disposed of after 5 to 7 years. Not sure where you got that idea from.
Last I heard, London tenders were renewed after five years, with an option of an extra 2 for good behaviour, and the tender invariably called for a new bus.

No one - they couldn't get anyone to buy them in UK or elsewhere. They're owned by TfL (rather than the operators) so they will be in London until such time as they're withdrawn which, given they're coming up to 14 years old, won't be far away. That said, I think the newest are 10 years old. The end of an error...
It was never the original plan to sell New Routemasters operating in London on the second hand market. They were to be used for their whole life, in London. You're mistaking several different aspects of the original project, and maybe later proposals too, by the looks of it.
 

Goldfish62

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Last I heard, London tenders were renewed after five years, with an option of an extra 2 for good behaviour, and the tender invariably called for a new bus.
I'm afraid you heard incorrectly. Tenders are currently usually 7 years with no extension. Compliant bids with new buses are mandatory, but alternative bids with existing buses refurbished to TfL's specification are allowed. This is why the projected life of buses in London is 14 years. There are plenty of 14-15 year old buses still running around in London.

The use of buses for a second contract term has been going on for as long as I can remember and I've been involved in many such tenders in a previous life.
 
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Magrar

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It quite possibly was. The extra weight of proper aircon could well have made its fitment impossible. Double deckers tend to be three axle in mainland Europe to take account of this weight.
AFAIK The New Routemaster was the first bus design where you could at least hope, and may well plan for, a reduced axle weight over time, freeing it up for an air-con retrofit.

Either because the hybrid batteries got lighter with each generation, or it became possible to convert it to full electric. Even a small hybrid ICE is a heavy lump of metal.

I think people forget the Borismaster was a contemporary of the Nissan Leaf, not later efforts at either hybrid or even all electric mass produced vehicles. If it had still been in production now, it would have significant differences to the first design, while retaining commonality of parts and an overarching look.
 

Goldfish62

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Apart from the 358, are there any other TfL routes where buses are routinely operated with windows locked?
No, because no buses have yet been delivered under the the latest vehicle spec

== Doublepost prevention - post automatically merged: ==

AFAIK The New Routemaster was the first bus design where you could at least hope, and may well plan for, a reduced axle weight over time, freeing it up for an air-con retrofit.

Either because the hybrid batteries got lighter with each generation, or it became possible to convert it to full electric. Even a small hybrid ICE is a heavy lump of metal.
Given that considerable work had to be done to get it up to 87 capacity due to weight issues I doubt very much if any significant weight could be saved.

The one bus converted to electric wasn't exactly a stunning success

== Doublepost prevention - post automatically merged: ==

It was never the original plan to sell New Routemasters operating in London on the second hand market. They were to be used for their whole life, in London. You're mistaking several different aspects of the original project, and maybe later proposals too, by the looks of it.
I think what @TheGrandWazoo meant is that the attempts to sell new Borismasters on the open market was a dismal failure. Hardly surprising given the buses are complete junk!
 
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Magrar

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I'm afraid you heard incorrectly. Tenders are currently usually 7 years with no extension. Compliant bids with new buses are mandatory, but alternative bids with existing buses refurbished to TfL's specification are allowed. This is why the projected life of buses in London is 14 years.

The use of buses for a second contract term has been going on for as long as I can remember and I've been involved in many such tenders.
Are we to assume then that inner London routes and other high profile services get brand new buses every seven years, and the less important outer boroughs get their seven year old cast offs? Refurbed, naturally.

And to keep this on topic, does that then mean the less important parts of the London bus network won't be getting buses that were specifically designed and built with air-con as new, until ~2040? If we assume air-con is the new standard from now.

I ask on the assumption that retrofits, especially if done as small batch jobs, will be inherently less reliable or even less effective, than a brand new bus or a fleet wide upgrade.
 

Goldfish62

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Are we to assume then that inner London routes and other high profile services get brand new buses every seven years, and the less important outer boroughs get their seven year old cast offs? Refurbed, naturally.

And to keep this on topic, does that then mean the less important parts of the London bus network won't be getting buses that were specifically designed and built with air-con as new, until ~2040? If we assume air-con is the new standard from now.

I ask on the assumption that retrofits, especially if done as small batch jobs, will be inherently less reliable or even less effective, than a brand new bus or a fleet wide upgrade.
Not necessarily. Most new electrics until recently have gone anywhere except Central London, partly due to Borismasters being concentrated there but also simply because TfL does not favour any particular routes or areas for new buses. You're just as likely to get new buses in Biggin Hill as you are in Westminster.
 

Magrar

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I think what @TheGrandWazoo meant is that the attempts to sell new Borismasters on the open market was a dismal failure. Hardly surprising given the buses are complete junk!
He clearly didn't mean that. He was answering the question "Who would want to buy second-hand new Routemasters?" with "No one - they couldn't get anyone to buy them in UK or elsewhere."

Unless something happened later in their life that I missed, I know of no attempt to sell second hand New Routemasters (in batch terms) by TfL or indeed Wrights.

All I remember is the strategy of marketing the more basic "provincial" model to non-London operators to bring down the unit cost for London. And I guess, selling small numbers of actual London spec New Routemasters to operators looking to bring the benefits of that design to their niche markets.

I suspect the former failed for reasons of rapidly changing economics, which is hardly new for the bus industry, and the latter due to the issues with the London model in London.

No big deal I suspect. It would have been nice, but not essential. Just like the original Routemaster. That attracted no significant non-London interest, but it was enough of a benefit to London that it didn't matter.
 

TheGrandWazoo

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Last I heard, London tenders were renewed after five years, with an option of an extra 2 for good behaviour, and the tender invariably called for a new bus.


It was never the original plan to sell New Routemasters operating in London on the second hand market. They were to be used for their whole life, in London. You're mistaking several different aspects of the original project, and maybe later proposals too, by the looks of it.
Er no and no... @Goldfish62 is on the money regarding what I was driving at.

The TfL examples were purchased by them and they were always destined to be employed in London. However, Boris declared great hopes for export success and indeed, ones were sent on a year long (or more) trade mission to drum up potential orders in China and South East Asia e.g. Singapore, hoping to capitalise on long standing trade agreements and the supply of deckers to such places. In addition, one was liveried up for evaluation in Leeds (First Leeds trying to woo Metro with buses so they'd forget about trams or trolleybuses) and on the Tayway services in Dundee.

Of course, there were no orders from anywhere other than London. The spec and the price tag was just much for provincial (or foreign) operators. Hence my comment that "they couldn't get anyone to buy them in UK or elsewhere" and my agreeing with the poster that they wouldn't be attractive to operators as a secondhand purchase even if TfL did try to offload them. The reality is that some examples might get preserved but most will be heading to Carlton in the coming years!
 

ValleyLines142

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I was on a Metroline BYD on the 98 yesterday from Edgware Road to Tottenham Court Road and I was dreading the journey, but the aircon was fantastic.
 

Magrar

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Er no and no... @Goldfish62 is on the money regarding what I was driving at.

The TfL examples were purchased by them and they were always destined to be employed in London. However, Boris declared great hopes for export success and indeed, ones were sent on a year long (or more) trade mission to drum up potential orders in China and South East Asia e.g. Singapore, hoping to capitalise on long standing trade agreements and the supply of deckers to such places. In addition, one was liveried up for evaluation in Leeds (First Leeds trying to woo Metro with buses so they'd forget about trams or trolleybuses) and on the Tayway services in Dundee.

Of course, there were no orders from anywhere other than London. The spec and the price tag was just much for provincial (or foreign) operators. Hence my comment that "they couldn't get anyone to buy them in UK or elsewhere" and my agreeing with the poster that they wouldn't be attractive to operators as a secondhand purchase even if TfL did try to offload them. The reality is that some examples might get preserved but most will be heading to Carlton in the coming years!
Had TfL tried to offload some buses second hand and been knocked back, this might have made some sense as an over arching argument that the bus is complete junk. But since they haven't, it doesn't.

For a historical comparison perhaps, the Daimler Fleetine (DM/S) was a truly terrible London bus. Not only did it not run in London for its full design life, they did cut their losses by selling it on the second hand market.

They must have sold it very cheaply, maybe even given it away, because the main issues with the bus were things a non-London operator would be even less willing to tolerate rather than shell out for a new bus, than London. It was unreliable and hard to maintain.
 

TheGrandWazoo

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Had TfL tried to offload some buses second hand and been knocked back, this might have made some sense as an over arching argument that the bus is complete junk. But since they haven't, it doesn't.

For a historical comparison perhaps, the Daimler Fleetine (DM/S) was a truly terrible London bus. Not only did it not run in London for its full design life, they did cut their losses by selling it on the second hand market.

They must have sold it very cheaply, maybe even given it away, because the main issues with the bus were things a non-London operator would be even less willing to tolerate rather than shell out for a new bus, than London. It was unreliable and hard to maintain.

Let's not invent things. I didn't say it was complete junk. I said that the spec and price tag made it unattractive to buyers when it was offered as a new product. Which is true - demonstrated by the non London sales being zero. What I also said is that it would be unattractive on the secondhand market because of the spec - I can't see operators wanting an elderly, two staircase, three door hybrid decker when there are many other off the shelf options that they could have.

The early DMS's didn't run for their full design life (they were sold at their Certificate of Fitness deadline) so many early ones lasted only 7 or 8 years - famously the first ones were withdrawn and sold only 12 months after the last ones were delivered. They were a largely standard design that LT's very defined maintenance procedures couldn't bend to accommodate, and were eagerly snapped up by provincial operators who operated them alongside their existing fleets. So whilst they were sold cheaply, and there were some London specifications/oddities, they were a decent bus that had a lot of similarities with what they already had. In fact, many operators were astonished by how relatively simple "issues" like shackle pin maintenance was simply not undertaken properly. However, the later examples (B20) did operate across their design life (from the late 1970s until sale in the early 1990s) and whilst a few did get sold to Midland Fox or some indies, most of those were sold straight for scrap though the dynamics of the secondhand market were beginning to change then.

Not certain that NBfL represents any sort of parallel and it's rather off topic for the thread.
 

ChrisPJ

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Air con is all very well but you have to MAINTAIN it, if an aircon equipped bus has fewer or no opening windows then failure makes it even worse on board than a bus which had no air con in the first place
 

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