General How's the air con in the Panda?

[SB1500]

I was thinking about how well the air conditioning can get the cabin of the Panda chilled on a hot 30˚ day like today as I drove home for 45 mins in my older model without air con.. decided it's now a must for the next Panda

Is it sore on the fuel consumption for the 1.2?

 

[AB100]

I was thinking about how well the air conditioning can get the cabin of the Panda chilled on a hot 30˚ day like today as I drove home for 45 mins in my older model without air con.. decided it's now a must for the next Panda

Is it sore on the fuel consumption for the 1.2?

We have climate in the Lounge and manual in the Dynamic. Both as good as each other though the climate means laziness/ease. They are effective of course, though more useful in winter than the week of summer we've had.....

Fuel consumption/power loss I imagine are marginal and unnoticeable.

 

[Al D]

Allegedly opening window uses almost as much fuel as air con. Lack of use of air con could cause massive repair bill that makes bit of fuel lost look like chicken feed. So use it. Had mine permanently on since a Citroen Xsara TD SX in 2003. Had a fan fault on that in this sort of weather. The seats were as soggy as me. Horrid. :yuck::yuck:

 

[Herts Hillhopper]

more effective still if, once the car's cooled a bit, the controls are set to recirculate, as its not having to chill such warm air to start with.

 

[The Pretender]

I have also climate in the Lounge, turn it on when i collect the car and is running ever since non-stop when i'm using the car.

 

[murphyv310]

Mine has the basic system and it works a treat. It is used around 90% of the time so its difficult to see if it has a bearing on fuel use. Most of my driving is in town and I'm more than happy with the fuel consumption of my Panda.

 

[Wee Smurf]

Lol I know how you feel Shane. Mine is probably worse than yours ATM with the skydome making it the perfect little greenhouse and no air-con.

 

[jrkitching]

I was thinking about how well the air conditioning can get the cabin of the Panda chilled on a hot 30˚ day like today as I drove home for 45 mins in my older model without air con.. decided it's now a must for the next Panda

Is it sore on the fuel consumption for the 1.2?

Assuming it's in proper working order, the A/C in the 1.2 is perfectly capable of cooling the car on a 30˚ day (remember this wouldn't be considered hot for a summer day in Southern Europe).

The radiator fins on the A/C condenser do tend to corrode away quite quickly in the UK climate (you'll see this quite clearly if you look behind the grille on a car that's more than a couple of years old), but this doesn't seem to have a great deal of effect on its performance.

A/C uses quite a bit of power, and the impact on economy is greater than most folks realise - though that shouldn't put you off using it. The exact percentage will depend a lot on the outside temperature, the kind of journey you're doing, and the way you drive. Expect a drop of somewhere between 5% and 20% when it's in use - the percentage effect is significantly greater if you're an ecodriver. Some folks will claim it's marginal, but this is wishful thinking and really just shows how hard it is to measure a 10% change in short term fuel economy, combined with an understandable reluctance to drive on a hot day with the windows shut for the 100 miles or so it takes to get a reasonably accurate consumption reading.

The generally accepted wisdom is that, in fuel cost terms, it's more efficient to open the windows below 50mph, and turn on the A/C above that.

In cruise at a steady 50mph on the motorway on a 30˚ day with the windows shut, you'll lose about 10mpg. At 70mph, you'll probably lose only half that. Open the windows, and you'll lose some or all of what you'd otherwise save.

In short, use it when you need to, and turn it off when you don't (but run it for at least a half hour once a week to keep the system in good order). Running it continuously is the equivalent of keeping the central heating on and opening the window if you feel a bit too warm. Turn it on in mild (8-15C) but damp weather, as it's an extremely efficient dehumidifier (mine sees more use in winter than summer).

Also, despite what some folks think, in the UK it's not a 'must-have'; the vast majority of motorists managed just fine without it for most of the first 100 years of motoring. Until about 1980, it wasn't even an option on any but the most top of the range vehicles.

Also keep an eye on the temperature gauge if you're using it on a hot day in slow moving traffic; if the coolant temperature rises above normal, turn it off (and if it doesn't go down, turn the heater up to maximum). If the cooling system is in good order, this is unlikely, though you'll probably notice the radiator fan cutting in and possibly switching into fast mode. Turning the A/C on when stationary with the interior fan on its highest setting is actually a good way of checking the radiator fan is working correctly, as this will almost always kick it on.

To maximise engine life, when starting from cold, leave it off until the engine has reached operating temperature.

 

[AndyRKett]

Assuming it's in proper working order, the A/C in the 1.2 is perfectly capable of cooling the car on a 30˚ day (remember this wouldn't be considered hot for a summer day in Southern Europe).

The radiator fins on the A/C condenser do tend to corrode away quite quickly in the UK climate (you'll see this quite clearly if you look behind the grille on a car that's more than a couple of years old), but this doesn't seem to have a great deal of effect on its performance.

A/C uses quite a bit of power, and the impact on economy is greater than most folks realise - though that shouldn't put you off using it. The exact percentage will depend a lot on the outside temperature, the kind of journey you're doing, and the way you drive. Expect a drop of somewhere between 5% and 20% when it's in use - the percentage effect is significantly greater if you're an ecodriver. Some folks will claim it's marginal, but this is wishful thinking and really just shows how hard it is to measure a 10% change in short term fuel economy, combined with an understandable reluctance to drive on a hot day with the windows shut for the 100 miles or so it takes to get a reasonably accurate consumption reading.

The generally accepted wisdom is that, in fuel cost terms, it's more efficient to open the windows below 50mph, and turn on the A/C above that.

In cruise at a steady 50mph on the motorway on a 30˚ day with the windows shut, you'll lose about 10mpg. At 70mph, you'll probably lose only half that. Open the windows, and you'll lose some or all of what you'd otherwise save.

In short, use it when you need to, and turn it off when you don't (but run it for at least a half hour once a week to keep the system in good order). Running it continuously is the equivalent of keeping the central heating on and opening the window if you feel a bit too warm. Turn it on in mild (8-15C) but damp weather, as it's an extremely efficient dehumidifier (mine sees more use in winter than summer).

Also, despite what some folks think, in the UK it's not a 'must-have'; the vast majority of motorists managed just fine without it for most of the first 100 years of motoring. Until about 1980, it wasn't even an option on any but the most top of the range vehicles.

Also keep an eye on the temperature gauge if you're using it on a hot day in slow moving traffic; if the coolant temperature rises above normal, turn it off (and if it doesn't go down, turn the heater up to maximum). If the cooling system is in good order, this is unlikely, though you'll probably notice the radiator fan cutting in and possibly switching into fast mode. Turning the A/C on when stationary with the interior fan on its highest setting is actually a good way of checking the radiator fan is working correctly, as this will almost always kick it on.

To maximise engine life, when starting from cold, leave it off until the engine has reached operating temperature.

Although all this advice would have been very much spoton 20 years ago, these days a lot of it is consigned to the history books.

The amount of fuel a modern aircon system uses is negligible. You can run it all day everyday and still barely notice a dent on the fuel economy, cars can change their ecu engine map at the flick of a switch and they can have a different map for running and not running the aircon. You shouldn’t really buy into the open the window at lower speeds myth that still goes around, modern systems are far too clever for this to apply anymore. Ecu maps don’t get changed because you open a window

If climate control then sunload sensors and internal temperature sensors as well as coolant all work together to make the system as economic as is possible while also increasing comfort.

Most will, for example not blow freezing air in your face in an attempt to warm up the car on a cold day. Instead waiting for some engine heat before ramping up the fans.
Bright hot sunny day the sun load sensor will have the system work harder to cool the car down, then it would at a similar temperature in the evening after the sun has gone down.

If you stop with the aircon on the fan will almost certainly always be on cooling the condenser, the system won’t work without air moving through the condenser and as a result unless there is a fault with the engine or coolant system, then running the aircon will not in its self cause any over heating problems.

A good working system would expect to see a 15’C drop on ambient temperature so if it’s 30 outside a nice comfortable 15 will be blowing out the vents.

My experiance of fiat air con is that they are little cars with big windows, so on very hot days can struggle to keep it comfortable if the sun is exceptionally bright, however this can be easily resolved with a slight window tint which I did with my mk2b punto making it nice an cool inside even on the hottest day.

I wouldn’t if I were you have any concerns about the aircon on a pande, Fiat make pretty good fridges on wheels

 

[jrkitching]

The amount of fuel a modern aircon system uses is negligible. You can run it all day everyday and still barely notice a dent on the fuel economy...

We've had this discussion before.

Unfortunately, that's just not true.

I'd agree modern A/C systems are much improved from those of twenty years ago, but in the final analysis, there's no way round the basic physics.

Just calculate the power needed to cool the car by 15C, calculate the power needed to propel the car at a steady 50mph, and compare the two. No amount of fancy electronics can change the fact that the additional power needed to cool the car has to be paid for in fuel.

 

[AndyRKett]

We've had this discussion before.

Unfortunately, that's just not true.

I'd agree modern A/C systems are much improved from those of twenty years ago, but in the final analysis, there's no way round the basic physics.

Just calculate the power needed to cool the car by 15C, calculate the power needed to propel the car at a steady 50mph, and compare the two. No amount of fancy electronics can change the fact that the additional power needed to cool the car has to be paid for in fuel.

Take fuel efficiency figures from a car 20 years old with a 1.2 litre engine, then take a modern 1.2 litre engine’s figures, then compare the relative weight of the vehicles and you’ll find the much lighter older car to be considerably less efficient than the modern much heavier car.

Ecu software is infinitely tweekable a manufacturer can easily map out the impact on fuel economy of an air con system. Especially as cars are mapped to be robust, rather than the best possible level of performance.

A typical car aircon system only has a very very small area to cool and therefore require less then half a KW when operating at maximum load once the car has been cooled inside the amount of energy needed to keep it cool is very small, as the physics of the air con system kicks in.

 

[jrkitching]

A typical car aircon system... requires less then half a KW when operating at maximum load once the car has been cooled.

Source?

 

[AndyRKett]

Maths.

A car interior takes up a very small space, in something like a panda the volume of air that needs to be cooled would be about 2-3 cubic meters
There are various calculators out there which factor in occupants, required temperature drop, types of insulation etc but given a 3 cubic meter space and having compared a few calculators, you would typically need less than 1500btu which equates to less than half a KW

A 9000btu home air conditioning unit is enough to cool a small room say 3 metres square by 2.5 meters high and would only use about 2.5-3kw and this is a massive space compared to a car interior.

 

[andydiver]

Not wishing to overheat this discussion just been looking at motorhome air conditioning units and they are about 1.5 to 3 kW. However a car would be somewhat smaller, let's use 1kw as a round number. If a car needs 7.5kw to maintain 40km/hr then the air con is noticeable. At 80 km/hr that same car will need 30kw. So the relative fuel consumption with air con is vastly different with speed as prev noted. The compressor will be pumping harder for less time with higher revs at speed. A decent ecu would use scavenge energy every time you coast and so on. That said remember ploughing in heavy land with a 110hp (82kw) tractor in lowest gear, 1800 RPM (peak torque) and noticing the engine slow when the air con cut in.....

 

[AndyRKett]

Moving gas around an aircon system is a lot like moving a car along a road, when you start off you need more energy to get the car going, the same applies to aircon you need more power to begin to move the gas around the system when you first turn it on, once the gas is moving it requires less energy to keep it moving.

Secondly aircon is not just dealing in motive energy it’s also pumping heat which means when it starts off the system needs more energy putting into the system to move more heat out of the cabin.
Once the temperature of the interior of the car is reduced, once again less energy is needed to keep it cool essentially once down to temperature the aircon system may only use 100-200W to keep the car cool, which when you factor in the headlight bulbs on a car are 55W each, the aircon system losses are virtually non existent.

This also means if you run the aircon in the winter when there is no intention to make the car any colder then aircon system is also using less energy than on a very hot day. Which is why you can leave air con switched on all the time with little impact on fuel economy.

And as previously stated sophisticated engine management systems can reduce this even further

 

[jrkitching]

Once the temperature of the interior of the car is reduced, once again less energy is needed to keep it cool essentially once down to temperature the aircon system may only use 100-200W to keep the car cool,

A car isn't a small room, it's a small greenhouse. The real figure for the steady state cooling requirement on a hot day is about ten times that, and for the initial knockdown time (about 10 minutes or so), the A/C load will be closer to 3kW. Just the direct solar heat gain on a summer's day is about 1kW. 200W won't even cover the body heat produced by a couple of occupants.

Read this to find out how the calculation is done by the experts who actually know what they're talking about, and study the experimental evidence they gathered to support those calculations. The case study in this paper was based on a Suzuki Wagon R, which is of a similar size and form to the Panda.

Sometimes when posting technical information on this forum, I feel like I'm talking to flat earthers.

For anyone interested in pursuing this further, the truth is out there - but you need to check your sources carefully and exercise the usual caution about believing what you read on the internet.

 

[AndyRKett]

A car isn't a small room, it's a small greenhouse. The real figure for the steady state cooling requirement on a hot day is about ten times that, and for the initial knockdown time (about 10 minutes or so), the A/C load will be closer to 3kW. Just the direct solar heat gain on a summer's day is about 1kW. 200W won't even cover the body heat produced by a couple of occupants.

Read this to find out how the calculation is done by the experts who actually know what they're talking about, and study the experimental evidence they gathered to support those calculations. The case study in this paper was based on a Suzuki Wagon R, which is of a similar size and form to the Panda.

Sometimes when posting technical information on this forum, I feel like I'm talking to flat earthers.

For anyone interested in pursuing this further, the truth is out there - but you need to check your sources carefully and exercise the usual caution about believing what you read on the internet.

Oh very dear....

The thermal loads talked about in this article are not the same thing as the energy needed to be put in to power an air conditioning system.

Go look at the stats on a portable air conditioning unit, they will have a cooling capacity of 3kw of thermal load (around 10,000 btu) enough for a 20+sq/m room (not a tiny 2-3sq/m hatchback car) and use about 1kw of electrical energy to power.

Also as a side note you’re making a comment about not believing everything you read on the internet and substantiating your post with an article off the internet, written at an Indian university and lists the authors email addresses as Gmail accounts.

 

[jrkitching]

I'll leave this here, I think. There's no point in presenting good science to someone who isn't listening with an open mind.

 

[murphyv310]

When I look at my fuel consumption figures they are about 3-4 mpg lower than average so about 10% higher than expected. In reality as the engine is never running at full pelt it will be producing less output, let's say its average is 20kw to allow for hills and acceleration full loads carried etc, now I'm using 10% more fuel so a really rough calc means I'm using an extra 2kw somewhere, so using my aircon most of the time is perhaps the culprit.
There is no way on Gods earth an aircon system only uses 200 watts, why do you think the ECU compensates so much when it engages?
Im in total agreement with JRK.

 

[babbo_umbro]

I'm confused - am I the only one. What I know is that my previous 100HP had climate control on permanently, except when I turned it off to see if the mpg changed. It didn't by a noticeable amount. Likewise the aircon in my current 4x4 TA - no significant difference.