Cold feet, is it just me

[Jonathan 13]

TBH the Esprits I've owned have never been that good with heating and ventilation, and I cant really see why...

Usually it's caused by the dial or the cable not being correctly set (on the pre 98 cars) - mine are fine, I do get luke warm air from the 'heater' and I am aware of the -unmarked- position on the heater dial.

However my feet are FREEZING again and I wondered has anyone got an Esprit that heats up well ?

I was going to rip the dash apart and try and locate the problem.

I know of issues with the piping falling off etc, I know about the bowden cabled and so on - is it a case of the heater matrix is too small or gets blocked easily ?

[Guest mkelite]

if it helps........ ive had this issue with a number of cars, especially when ive just got s/h ownership of one - and found in a lot of cases that when the antifreeze was changed in the rad, the heater controls were not on hot and needed bleeding again. may not be the case with the Esprit but worth a mention? DC.

[Jonathan 13]

Yep it is worth a mention - I know when you bleed it all the heater must be set to full in order to open the valve and let the fluid out.

Mine was done last by a specialist so who knows (why I like to service the car myself) it does come through but only slightly warm air.

[Sparky 2,941]

Mine's lovely & warm & cosy.

[rocket63 137]

Im with you Jonathon. Heaters on all the Lotus I have owned, new and old are just the very worst. End of. And No its never been related to an air lock either, they are just crap.

[Bibs 11,665]

You can cook food in the footwells of the 350, heaters are amazing and aircon is ice when you want it! You're welcome to come see if it helps?

[Simon350S 192]

Is there a valve in the water flow to the matrix? I thought there wasn't. Infact the later cars have the outlet from the cylinder head plumbed directly to the matix inlet so should never block up unlike the early esprit where the water could bypass the matrix and therefore was susseptable to blockage.

[steamdriven 2]

Cold feet - me too ! And no hot air to the screen.

I previously owned a '98 GT3 and got warm as toast (needed to because i lived in Aberdeen at the time)

I now have another '98 GT3 (which i picked-up in the summer) and have struggled all winter with the cold and lousy/non existant de-mist.

I have been researching several threads on this topic and feel overwhelmed and confused (matrix, diverters, solenoids, vacuum actuators...etc). I added to this thread because it is the most recently used -in the hope that someone out there can help; I get plenty of air blowing through the main cabin vents but none at all that i can detect flowing through the screen vents or the footwell pipes (yes the pipes are in-tact and connected). I contorted myself into the drivers footwell today and felt the water hose that I think supplies the heater matrix - it was getting hot so I guess water must be getting there but the blower is not moving air across it ??. I also observed that an actuator (stepper motor ?) - also in the drivers side footwell - is moving according to the cabin console control (cabin air to face, feet, demist etc).

Is there something I can do to track the problem down, or better still a simple solution ?

[Jonathan 13]

If you have a 98 chances are you have the electronically controlled dials, the pre 98 ones had the old faithful bowden cables and clunk switches.

Mark B on here sent me his stepper motor once to try and repair and that had burned out which meant none of the diverter flaps would move regardless of the dial setting - thats where I would start my search.

Simon - pretty sure there is.

I'm pretty sure the blower diverts air over the matrix regardless, what you have is a temperature setting on the dash which is connected to a cable that opens or shuts the valve on the heater matrix.

My issue is the heater works but only very poorly, it's never been brilliant and I wonder whether it's a trait or somethign that can be serviced / fixed.

I have to have mine on full blast to really get any heat significant from it and even then it's not really that warm.

I guess it's time for sunroof off and a diver under the dash again...

[cjtpb13 12]

Mine has absolutely no issue with producing heat, whether it is for the floor or the defroster for the windscreen. Now fan speed is something else...

[steamdriven 2]

Thanks Jonathan; and from entries here and on other threads it seems that the esprit heater can work just fine (but ofeten doesn't).

Anyone know where the stepper motor that is controlled by the cabin temperature knob is located (post '98 - electronic dials) ; how do i check it out ?

[Jonathan 13]

You might try contacting Mark 'Loosecannon' on here as I dont know myself.

[Loose Cannon 582]

Jon - I wasn't going to add to this seeing as you helped sort my stepper motor - like rubbing salt in the wound! My heater has always been fine, it was the distribution that was a problem, hot screen/cold feet. Turning the distribution dial you should faintly hear the stepper motor working. From memory it only has two positions anyway, which seems a complicated solution to something that could be done by a cable, but hey ho. Location it's behind the radio and slightly to the right.

I got to it by manhandling it from underneath the dash/drivers footwell and using an 18" long phillips screwdriver through the radio aperture. This was due to my screen pillar covers being "accidentally" bonded in by Autoglass which negated removal of the middle dash panel which would have made things much easier. The arrangement of the 3 screws is set up to favour LHD installations, and Lotus fabricate a little bracket to turn it around which makes screw access difficult

If you need the stepper motor it was unavailable and on back order at Lotus, but that was some time ago. It was a generic Diavia part, but the number had worn off the casing (obviously I have that now if you diagnose this and need one). Brian Angus searched the factory himself to find the last one available, God bless him.

[steamdriven 2]

Please excuse my ignorance - I did say that this HVAC stuff is a bit daunting ; but my 'distribution dial' sure enough activates a stepper motor which I can both hear and see working, but the stepper seems to be in the drivers footwell. Is the stepper that is behind the radio perhaps connected to the 'hot/cold' dial ?. The fact that my 'distribution dial' seems to activate ok, makes it odd that I don't get any airflow onto the screen or into the footwell, but it blows a gale and lifts my hairpiece (only joking - honest) when the dash vents are open.

[steamdriven 2]

Just to add that I have now managed to figure-out the configuration of the heater and ventilation system on my 98 Esprit (various diverter flaps conrolled by a mixture of stepper motor and vacuum actuators) ......and now get stacks of hot air into the footwell and/or screen, when i need it. No more cold feet for me...............

[matk 17]

Might be useful though if you could actually say what you did to yours for any one else with a similiar future prob to reference?

[steamdriven 2]

Mat,

You are right Mat and i intend to post a detailed description once i have finally fixed the problem (i have still not got all the vacuum actuators working):- There have been quite a few threads on this topic, including this one 'Heater Control Module for GT3- Supplier ?' which i started recently when i thought that the control module was the problem.

I am a newby here and have been reluctant to demonstrate my ignorance amongst the experts, but I think a run-down on the HVAC for post 98's would be useful; It has taken me ages to figure out how it all functions.

[Glyn Wise 2]

Hi all,

Its nice to hear im not the only one with cold feet and no air flow over screen,today I started to resolve th problem of heat.

And may I say all the posts I have read have started me off on a fault finding trip,without those Ide have been lost.

So checked under drivers foot well with torch and mirror and reconnected a vacume elbow.

Had the radio out and re tighten outer sleeve clamp on temp dial which had pulled through.

And finally bleed rad,thats a start.

Tomorrow Ill check out the vacume pump and all connections in engine bay,I take it the pumps in there on an s4s.

Ive noticed there should be a foam seal around the air intake flap in the front luggage comp,

I presume this should be shut when on de mist and dragging in unwanted cold air is not good.

Ive had a slight temp rise on screen with poor air flow unlike facia vents a bloody gale out of those,

see what tomorrow brings.

By the way fixed window prob good dose of wd 40 down the rubbers and its up and down quicker

than Jordan's.

Cheers Glyn

[steamdriven 2]

Glyn,

"Ive noticed there should be a foam seal around the air intake flap in the front luggage comp,

I presume this should be shut when on de mist and dragging in unwanted cold air is not good."

This flap should be normally open, and it closes when you set the controls to 're-circ'. When i had my heater problems, this flap was fixed in the closed position and I found that it was controlled by a vac solenoid. If there is no vac supply to this solenoid then the flap stays shut.

"Ive had a slight temp rise on screen with poor air flow unlike facia vents a bloody gale out of those,

see what tomorrow brings"

If you look in the passseneger footwell, to the side of the centre console, you will find another vac operated solenoid. This solenoid operated a diverter flap which send air to screen rather than to facia. If you disconnect solenoid actuator you should find that you can then manually operate the diverter flap and test that you can send air to the screen, rather than the facia vents. This vac solenoid is operated when you set the controls to 'de-mist'. Again, this is the same problem that i had - and it sounds like your problem problem could be is a break in the vac supply to that solenoid - most likely at one of the rubber connection junctions, or a crack in on of the rubber connectors. (You should be able to divert that 'gale' to your screen !)

Edited December 1, 2010 by steamdriven

[Glyn Wise 2]

Cheers Ian

Just got back from my garage for a warm,think Ive cracked it found it to be a dodgey electric plug conection on the vacume pump.

As you say vent open now and closes in recycle mode and air con,plenty of air on screen but ist still a tad cool .

Me thinks it needs a good blow out up the road and get it up to nornal temp, but not at mo til weather improoves.

Next job is to sort out the interior light it stays on all the time,mulitmeter at the ready!!!!!

Thanks Ian will post out come of heater.

Glyn

[Rich H 4]

That will be the door switches stuck, take them to bits and clean them up!