I've tried searching for an answer to the lack of heat in my 2010 Lexus RX350 and tried a few of the suggestions I found here - use A/C, don't use Eco mode, turn off rear heat, check dual temps but basically it just seems that it is poorly designed as far for heat distribution.

I will admit I prefer the car warmer then most but every winter it seems that I start to dislike the car when the temperatures drop below freezing. I start the car before leaving the house but it easily can take 10-15 minutes before a decent amount of heat is blowing, particularly on the floor over my feet. If I turn on the cabin vents the minimum heat flowing from the one small vent over my feet is reduced even further. If I need to use the defroster I do not get any warm air at my feet. The steering column itself does not seem to be well insulated and it appears the little heat that does flow from the floor must first warm that area before my feet feel any warmth. The heated seats do nothing to offset the cold interior until the car reaches a decent internal temperature. The temp gauge will be clearly at its mid range before I begin to feel even reasonably warm. Is this a known design flaw or is my personal internal gauge just faulty? My commute is less then 20 mins and there are times the car is just barely warming up when I pull into the parking lot. Any other suggestions?

My Ford Explorer had several vents the provided heat at the floor, the knee level and from the dashboard and would blow warm air more forcefully when required. He was a strong tough workhorse! She is lucky she is so pretty

 

Yup. It takes at least 15 mins to get a bit ok and 30 mins to get warm (bigger size than sedan???). My Toyota Corrolla takes 5 mins to get hot

 

Try installing a block heater and turning that on about an hour or so before departure.

 

I would guess possible thermostat issues or maybe heater control valve. Have you been to the dealer to have it looked at?

 

Found this on another forum. Maybe it'll help...

 

Peg234 - Something is definitely wrong with your heater. The hot water is supposed to flow immediately from the block after starting long before the thermostat kicks in. I start to get heat from my Highlander and our '11 RX350 about a quarter mile from home, and full heat about a mile from home. The car is started in an unheated garage that's above freezing, probably in the 40's at it's coldest. Anyway, from what you say, I recommend you take your chilly baby to a reputable repair shop to check the flow of coolant immediately upon start.
If your thermostat is stuck open, if you heater valve is stuck closed or your hot/cold air mixing valve is stuck in the cold position, all these will give you slow heat in my opinion.
Ray A.

 

I can vouch for that - it is me

At least he (peg234) getting some heat, we had none, or to be precise, there was none on the driver's side.

It was well and truly a unique problem and we're still not sure exactly what they replaced to rectify it except it cost a lot of $$$$

We don't go to that service center anymore, and at the the one we do visit now let it slip to me, while he was reading it on the screen during a booking, by saying, wow you sure spend a lot fixing that problem, close to $4,000 was all I could get out of him.

Not the first time having the extended warranty paid off.

 

Mine is pretty lousy, too. It eventually puts out lots of heat but it takes longer than it should.
I've also tried using the block heater but it doesn't seem to make a difference. (I'm not convinced the block heater works).
I'm planning on changing the cabin air filter because it's probably overdue, but I'm not holding my breath that it'll suddenly become a furnace.

 

I doubt you'll notice any difference by changing the cabin filter. I would go with RAYLOR4's advice which I agree with.

 

In my experience on older toyotas, a bad thermostat will show as low temperature reading even when the engine is already hot.

Btw, in my 2011, the highest that the temp gauge hit is the fourth line from cold. I think there are eight gradations. In the winter here in Ottawa, the car hits this operating temp after about four miles or so even when it's really cold, say -18 Celsius or zero F.

You can also put the circulation mode to Auto or set it to recirculate for a few minutes at a time so as to prevent the cold air from coming in. Needless to say that you'd need to watch the fogging that the humidity inside the car will create.

Do let us know how you resolve your issue.

EDIT: I went out this afternoon when it was around -8 Celsius (17 F) and the temp gauge hit the fourth line about 2.5 miles into my drive.

 

It has to be a broken thermostat or a clogged cooling system or stuck heater control valve. A good independent shop should be able to diagnose and fix this. I would put my money on the broken thermostat not letting the car heat up properly. This also affects mileage, performance and long term engine reliability. Get it checked out by a professional.

And a diagnosis question, does it now take longer to warm up, i.e. for the temperature gauge to get to the middle reading, than it used to before this issue occurred? If so, that is a sign your thermostat is stuck open. Most are designed to fail in the open position.