[bmwak]

With it becoming rather cold here, I've started to use the heating facilities of the E92 and I must say, it is rather slow at warming the car up (even when the temp is wacked up to a max of 28 degrees both sides and with all front and rear vents fully open).

Understandably a smaller cabin but my old BMW 1 Series with a similar heating setup heated up in seconds. Could this be a problem. I also use the heated seats at the same time - does this throttle the heating of the rest of the car when also on?

[Statler]

In terms of engine temperature reaching the right level for the heater to work, mine takes about two - three miles of B road driving before heat starts to come through. I've never found that whacking the climate control to 28 has any effect as it will usually blow just as hard when it's set to 21.

(Similar idea to your typical radiator thermo valve - the radiator runs as hot as it would if the valve was fully open until the temp is correct to shut it or pre-heating the oven, whacking it up to 220 degrees won't make it heat to 180 degrees any quicker...)

I've heated seats too so this takes the edge off and I also keep my coat on in the car, never been a fan of shirt sleeve driving in winter!
They put an electrical drain on the car, shouldn't affect the water based heater as far as I can tell.

My old e46 would have heated much quicker like your 1 series. May have been an extra pre-heater on them.

HTH

[DavS1]

Sure you're thermostat isn't knackered and stuck open?

My car starts to blow slightly warm air after say 1.5 miles, well on a cold morning this is when I notice the temp of the air has risen coming out of the vents, I'd be lying if I noticed when it was fully warm but i'd suspect around 3-4miles of 40mph driving

[sixpot]

Diesels run cooler, and therefore take longer to warm up. I have noticed this in other makes of cars too.

[ZURICH]

Just to stir up a little Envy I have a Webasto pre heater fitted "Thermo Top" I get real heat in about 30 seconds, unlike some pre heat setups, mine heats up the water as it enters the heater matrix so hot air is available straight away, most systems are plumbed to heat the engine first. total cost of kit and fitting was about £750.00 CHF 1000 and is soooo worth it.

[AlanYoro35i]

my heated seats heats up within 30-1 minute, warm air comes on starting from 5mins-ish..

[macck]

Yeah they seem to take ages to warm up. Had mine started for ten minutes before i left work and still wasnt warm once you start to drive its usually warms up after about a mile of driving.That we feature were you can remove keys and lock the car with the engine running is very handy.

[AlanYoro35i]

Originally Posted by ZURICH

Just to stir up a little Envy I have a Webasto pre heater fitted "Thermo Top" I get real heat in about 30 seconds, unlike some pre heat setups, mine heats up the water as it enters the heater matrix so hot air is available straight away, most systems are plumbed to heat the engine first. total cost of kit and fitting was about £750.00 CHF 1000 and is soooo worth it.

You must be absolutly afraid of the cold ...

[ZURICH]

Originally Posted by Yoro35i

You must be absolutly afraid of the cold ...

Not particularly but it does get chuffing cold here at times, went down to minus 30 for a week last February strange we have only had one day of snow this year so preparing for an absolute deep freeze session shortly. check out my iced up car in the "pics of your e90 snowed in"

Kev.

But if you cant find it, see below

ice covered car (versoix, switzerland)

[HighlandPete]

Leaving a cold diesel to warm up on idle isn't at all efficient, as there is such a small amount of heat to use, until the engine is working quite hard.

The faster warm up, at lowish ambient temperatures, has to be the PTC electric element in the HVAC system. It can even mask a slow warming engine, even a poor thermostat. Don't assume a cabin that gets some heat in a mile or so, heat is coming from a fast warming engine. The engine coolant may still only be 30 - 40-degrees.

Also remember the energy management will 'clock' functions like the PTC heater element, if the battery is low on charge, and/or the alternator is fully utilised. So warm up can be slow, due to the reduced output from the PTC element.

My 3.0d takes 8-miles to get to 78-degrees on the coolant, at about 5-degrees ambient. Can take much longer at cooler temperatures. To get to full heat, 88 - 91-degrees can take 14 miles. Particularly if I don't preheat the cabin before I start, with an external heat source. Cabins take a lot of heat to warm from cold.

HighlandPete

[chrismanchr]

i start mine and drive str8 away I dont sit and let it idle the heater warms up fairly quickly about a mile or so of driving I'd say that was pretty normal for any car ,instant heat can only come from a pre heater ,anymore than a mile or so or 5-10 mins and your thermostat might be knackered ,I had this problem on my e46 330i dead easy to change

[parapaul]

Petrol engines always warm up quicker than diesels - a LOT quicker.

I was sat in my car, idling from cold, for over 30 minutes the other morning, and the heaters were still blowing cool air. Normall takes about 5-10 minutes of town driving to get it warmed up properly.

[AlanYoro35i]

Originally Posted by ZURICH

Not particularly but it does get chuffing cold here at times, went down to minus 30 for a week last February strange we have only had one day of snow this year so preparing for an absolute deep freeze session shortly. check out my iced up car in the "pics of your e90 snowed in"

Kev.

But if you cant find it, see below

ice covered car (versoix, switzerland)

Fook me.. If u didnt tell me it was your car i would of thought it was a ice scrupture

[bmwak]

Thanks for the replies. Pleased to hear that it is a characteristic of the car than a fault.

I'll mention it anyway next time it goes in for a service next winter as still under new car warranty

[HighlandPete]

Originally Posted by bmwak

Thanks for the replies. Pleased to hear that it is a characteristic of the car than a fault.

I'll mention it anyway next time it goes in for a service next winter as still under new car warranty

More a characteristic of diesel engines, rather than the car itself.

As said in my previous post, there just isn't spare waste heat to enable a fast warm up from cold, in lower ambient temperatures. It isn't just a BMW issue, ever since DI with its greater fuel efficiency came to the diesel, it has been the case.

Hence why many have auxiliary heating. As examples, the E39 had a diesel fired auxiliary heater, the E46 an electric water heating element in the flow, some models like the E60 a combined PTC electric and water element and our cars the electric PTC element, working like a fan heater.

But if we have a high power demand on start up, the PTC element output will be reduced, it is a 1000W (max.) element, so we would notice its reduction.

The engine warm up cycle is also very slow if we are only running light loads. After all, it requires fuel to get waste heat. If our driving is low mpg through work, not idle, then we will typically get faster heat up cycles, but if we are light cruising, at high mpg, then we have a very slow warm up.

The more economical our diesel motors become, the bigger the issue with warm up and cabin heating.

HighlandPete



HighlandPete

[ALF_E90]

yes this is distinctly one of the benefits of throwing money at fuel for a large petrol engine. My various 6-pot petrols have all warmed up really quickly, warm air in a mile or two.

Try telling my retarded neighbours about the "no point idling a diesel engine to warm up" thing. They have a 118d and 320d and the woman - who seems to wear the trousers there - often leaves quite early for work, even at the weekends. She has been known to idle the car for over half an hour before driving off.

[HighlandPete]

Originally Posted by chrismanchr

i start mine and drive str8 away I dont sit and let it idle the heater warms up fairly quickly about a mile or so of driving I'd say that was pretty normal for any car, instant heat can only come from a pre heater, anymore than a mile or so or 5-10 mins and your thermostat might be knackered ,I had this problem on my e46 330i dead easy to change

Slow warm up in a diesel isn't necessarily a sign of a faulty thermostat. We just can't compare a petrol and diesel, enrichment in a petrol can be up to about 3 times as much on initial cold start, compared to the warm idle consumption. That contributes to the faster warm up, besides the cold mass issue of the diesel. The diesel doesn't have that same enrichment, although it does have a modified injection strategy, which uses more fuel due to being cold.

My 540i V8 used to warm very fast from cold, within 1.5 miles there was plenty of heat. Then so it should, it was using plenty of fuel during the initial warm up phase, so loads of waste energy as heat. It is only fuel that gives the heat after all.

My 330d running 3 miles to the next village from cold, will still only be reading 53C at low ambient temperatures. That is absolutely normal and repeatable. Requires the ambient to be above 10C to even get to 60C on the coolant.

Even when a diesel has warmed (with good thermostats) and correct coolant temperatures, it can cool off on light load, in low ambient temperatures. As will the oil temperature. I've seen this myself in my BMW diesel, and in VW vehicles.

Not uncommon to need over 12 miles to get full heat soak, at ambient's around freezing, and still the oil temperature is low.

HighlandPete

[doughboy]

Don't turn it up to max as that just blows the fans flat out blasting cold air in your face.

Just leave the climate on your regular 20 or whatever, then the fan will only start blowing gradually as the engine coolant warms up, increasing in force as it warms up then backing off as the set temp it reached.

[ALF_E90]

Try telling that to my wife!!

[HighlandPete]

Originally Posted by doughboy

Don't turn it up to max as that just blows the fans flat out blasting cold air in your face.

Just leave the climate on your regular 20 or whatever, then the fan will only start blowing gradually as the engine coolant warms up, increasing in force as it warms up then backing off as the set temp it reached.

Exactly, it will then warm in the fastest time possible, in a comfortable manner.

I don't think many folks grasp the concept of heating thermostats and will insist, if a room or building is not hot enough they must turn things up, even if the heating is already flat out and doing its best. Then they are the first to moan, if it gets too hot.

HighlandPete

[doughboy]

Ha Yeh,

It's a genetic fact that women cannot comprehend thermostatic control, we're burning £300 a month of oil at the moment and the missus wants to turn UP the thermostat as it gets colder outside.

Our 180,000 BTU boiler is already going like a SaturnVI rocket to keep the house at a steady 20 deg regardless of the outside temp (that's what thermostats do you know) but no matter lets go for 21 deg instead eh?

My side in the BM is always on 20, but hers is only ever on 16 or 24 and moaning about it being too hot or too cold.

Don't even get me started on radiator TRV's!

[Dr Dave]

£300/mth on oil??? You must live in a bloody mansion!!