Anyone had a problem with the heater not getting hot in there S1 ? Now winter is here I've noticed my heater is barely getting warm after 10-11 mile journey to work
Heater getting barely warm
- Thread starter iLikefishing
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Potentially a failed motor on the climate system. Can you get it scanned with VCDS as it should tell you which one if that's the case?
Hopefully not the failure requiring dash out!!
Hopefully not the failure requiring dash out!!
I really hope it doesnt need the dash out as that seems like a big job in small space, which usually means expensive, I will get it scanned to see if that shows what the issue is, I only have the analogue AC not dual zone climate if that makes any difference, I've read a few things online about a bag of silica possibly bursting and blocking the matrix, no idea if mine has one of these but I suppose checking will be a good idea, cheers Phazer 
Hi, the bag of silica is in the coolant reservoir and it has been known for this to burst and the silica granules block the heater matrix. Think this bag of silica is meant to prolong the life of the coolant. I removed mine - took a couple of minutes. And would rather change the coolant more often than risk a blocked heater matrix. Best of luck.I really hope it doesnt need the dash out as that seems like a big job in small space, which usually means expensive, I will get it scanned to see if that shows what the issue is, I only have the analogue AC not dual zone climate if that makes any difference, I've read a few things online about a bag of silica possibly bursting and blocking the matrix, no idea if mine has one of these but I suppose checking will be a good idea, cheers Phazer
My mechanic friend is going to scan my car this week and hopefully that will help, I removed the bag of silica from the header tank but it had no signs of bursting or leaking, blowers are luke warm after 10-12 miles, it used to be mad hot before
hmm what's the engine temp doing? Could be a sign of a failed thermostat. Thermostat/water pump failure is an EA888 engine speciality after all.
I had the water pump replaced about 3 years ago with an INA unit, engine temp rises to 90 after a mile or 2 and stays at that all the time, I'm guessing the matrix is blocked
Yeah sounds like the thermostat is all good. Could be a blocked matrix, pretty sure it's a dash out job to replace so worth attempting a flush out first.
My friendly mechanic says there is a valve and a secondary water pump as well as the matrix, still hasn't plugged his box of tricks in though to check for and codes and if the flap motors are working etc.
I'm totally flummoxed, my car had no error codes when checked and over the last few days my heaters have started working again, maybe not quite as good as they were but I now have warm air 
Some very cold mornings lately, heaters barely working at all, I'm thinking it's got to be the thermostat, hoping to get at it with just the centre console out, thinking a haynes manual or similar might help
Just found the step by step removal and refit procedure for my matrix and it doesnt invlove the dash coming out 
Good news! It was an audi dealer told me it was needed in a convo not related to my car, suppose I should have guessed lol Never had need to look it up but very pleased it can be done without!
Me too, it should, I’m hoping, make it a lot easier and cheaper, I found an Audi manual online for free, gotta love the internet for things like that
Audi Workshop Service and Repair Manuals > A1 > Heating, ventilation, air conditioning system | Heating and air conditioning | Air conditioner | Components of automatically controlled air conditioner | Removing and installing heat exchanger
A1 > Audi Workshop Service and Repair Manuals > Heating, ventilation, air conditioning system | Heating and air conditioning | Air conditioner | Components of automatically controlled air conditioner | Removing and installing heat exchanger
workshop-manuals.com
Thats a link to it in case it helps
Nissens heat exchanger was delivered today, hopefully my friendly mechanic can fit it soon and even more hopefully I will have heaters that work again
Never got this sorted and now it's cold again and I no longer have the luxury of having my friendly mechanic. My car has virtually no heat through the heaters whilst driving but strangely has plenty heat when idling stationary for a while, in both cases the guage reads a steady 90 degrees. Any advice on if this is still indicative of a blocked matrix or something else would be greatly appreciated. Local garage want £500 to replace the matrix but in my limited understanding if it was a blocked matrix I would get no heat when idling, or am I understanding this wrong ?
Hi - I’ve not had this issue, but I did get told by a friend with an S1 to remove the little nylon net bag containing white granules in the coolant filler bottle. These bags sometimes burst and the granules flow round the coolant system and block the heater matrix. So check your coolant filler bottle and see if this bag has split. It’s about 3 inches X 1.5 inches in size. If it has split then this is probably the cause of your heater problem.
what about hitting the recirculation button (to effectively block the outdoor fresh air entering the cabin). does this make any difference when driving?
do you get a full range of hot to cold air in the cabin when stationary running (i.e. from LO to HI on the climate control)? sounds like something is stuck open?
do you get a full range of hot to cold air in the cabin when stationary running (i.e. from LO to HI on the climate control)? sounds like something is stuck open?
Hi mate, I’ve tried it with and without the recirculation on and when stationery and it makes very little difference but sounds like is is opening and closing the flap. I get cold air when I turn the heater knob down to cold and hot when I turn it back up again, I reported this to the garage that quoted me £500 to replace the matrix and he said that definitely means it’s the matrix but, unless I understand it wrong, if the matrix was blocked I don’t think I’d get any heat when stationary???
or the flap to the matrix bypass is not blocked but "stuck" (as in constantly open)? so when you drive the movement of cool air coming through the rad is reducing the temp of the warm air you're getting when stationary?
Would it do this with the re-circulation on ? Or am I mistakenly thinking the matrix by-pass is different to the re-circ ? Pretty sure it works as when it's cold the car steams up with the re-circulation on, last week I was waiting in the car so had the engine running and the blowers on slow to keep the windows clear, after a while I felt warmth ( it was -1 outside ) I turned the blower up to full and the air stayed hot, then I turned it down to cold, the air went cold from the vents and then back to hot when turned up again, left the heater on full till it was too hot in the car and I had to open the windows, hoping this makes sense as its got me stumped apart from following the local garage diagnosis
I might be wrong but IIRC the recirculation button should only determine if any fresh (outdoor) air is allowed to enter the cabin mix with the air coming from the heating/cooling system. i.e. you'd want to close it as you pass the sewage treatment works.
the bypass flap is separate (I think) and this opens/closes based on whether you want hot air in the cabin (flap open) and using the warmed coolant for a source of heat or not (flap closed) so that the air coming in is mainly outdoor air that is refrigerated from the a/c.
I say this because there's a "tip" shared amongst us Lotus owners with K Series engines (renowed for Head Gasket issues) that if you think your car is getting too hot stuck in stationary traffic (no air flow to cool the rad/coolant) that you should turn the heater temperature to max (warm) so that you force the coolant into the heater matrix to assist with additional flow of coolant. leaving it cold means a shorter distance of travel for the coolant and faster to get to boiling (going pop point).
I might be a long way off, but maybe the test is to sit stationary, let the car warm up and pump warm air into the car, and then go for a drive.... if the air then cools then I think it tells me your heater matrix is stuck constantly open.
you might also be able to judge this in reverse, i.e. when it's warm it takes a while for the aircon to work efficiently as it's trying to cool a mix of warmed and outdoor air?
so it might not be the matrix per ce, just the flap that does the mix maybe it's not fully opening when you ask for heat and you only experience the symptom when moving around on a cold day.
I'm no mechanic, but trying to throw around some diagnosis steps as I'd hate for you to replace the matrix only to find the problem is still there. I guess Audi or Car heating specialist might be needed here.
the bypass flap is separate (I think) and this opens/closes based on whether you want hot air in the cabin (flap open) and using the warmed coolant for a source of heat or not (flap closed) so that the air coming in is mainly outdoor air that is refrigerated from the a/c.
I say this because there's a "tip" shared amongst us Lotus owners with K Series engines (renowed for Head Gasket issues) that if you think your car is getting too hot stuck in stationary traffic (no air flow to cool the rad/coolant) that you should turn the heater temperature to max (warm) so that you force the coolant into the heater matrix to assist with additional flow of coolant. leaving it cold means a shorter distance of travel for the coolant and faster to get to boiling (going pop point).
I might be a long way off, but maybe the test is to sit stationary, let the car warm up and pump warm air into the car, and then go for a drive.... if the air then cools then I think it tells me your heater matrix is stuck constantly open.
you might also be able to judge this in reverse, i.e. when it's warm it takes a while for the aircon to work efficiently as it's trying to cool a mix of warmed and outdoor air?
so it might not be the matrix per ce, just the flap that does the mix maybe it's not fully opening when you ask for heat and you only experience the symptom when moving around on a cold day.
I'm no mechanic, but trying to throw around some diagnosis steps as I'd hate for you to replace the matrix only to find the problem is still there. I guess Audi or Car heating specialist might be needed here.
I’m not a mechanic either mate, I will endeavour to find out if my car has a flap for the heater matrix as well as the re-circulation flap as I have no idea. Thanks for your thoughts they are much appreciated
Hi all, I'm after help again, after suffering what seems like forever with no heaters and being quoted mental prices to replace my matrix ( the likely suspect ) I swapped out the matrix myself. To be honest it was relatively easy once the centre console is out, however after re-assembly and refilling the coolant and bleeding the system ( ran with the header tank lid off till the bubbles stopped ) I still have zero heat. Whilst the matrix was out I watched the heater flap open and close when I turned the dial from hot to cold numerous times. What do I try next ?
Been trying to find out what else is in the heating system that could be the cause of no heat, I'm thinking maybe the heater control valve is my next step, anyone know where it is located ?
Did you use the pressure/vacuum tool to refill the coolant? If not there's probably an airlock. There's also the possibility of a failed thermostat but no idea what/where on the S1 as I've (thankfully) not had to look at mine
I didn't use this tool, I wasn't aware there was one, if it is an airlock it has been a pricey one so far lol, I was always lead to believe these were self bleeding but I may have been misinformed, hoping its not the thermostat as i'm sure that's a large job, had a new INA waterpump and housing a while back and I think the thermostat is incorporated in that ?
Can't speak for every engine but a lot of VAG need it done and the EA888 Mk3 definitely needs a tool to fill it correctly. I've attached the workshop manual pages, for any engine code references it's CWZA for the S1 obviously
There is a thermostat with the water pump, they should both be changed together just not worth doing one when they're both as likely to fail. I'm not sure if there's any more for the heater matrix. There's certainly two coolant pumps, one of which is electric. It might be worth you paying for half an hour's access to Audi Erwin and downloading all of the workshop docs and studying them.
There is a thermostat with the water pump, they should both be changed together just not worth doing one when they're both as likely to fail. I'm not sure if there's any more for the heater matrix. There's certainly two coolant pumps, one of which is electric. It might be worth you paying for half an hour's access to Audi Erwin and downloading all of the workshop docs and studying them.
Your a star mate, thanks for all that info, what is Audi Erwin ? Does the second water pump circulate coolant through the Matrix ? Any idea where the solenoid valve for the heater matrix is located ?
I'm pretty sure the guy who replaced my water pump told me it had the thermostat built into the same housing and if my memory serves me correctly the waterpump is behind/underneath the inlet manifold, (might be too big a job for me) the thermostat came with the new INA waterpump and is only about 3 or 4 years old, hoping it's not that as I no longer have the luxury of my friendly mechanics help :-(
No worries. Erwin is access to technical info. If you google it, you'll find the official site. It was something like 8Euro for 30 mins access - long enough to add your VIN and download all of the manuals for your car (all of it!!), the same docs as I screen grabbed for my earlier post. I had heard they'd removed the ability to save PDFs so ensure you have PrintToPDF/PDF Printer on your PC
I think the electric coolant pump is to keep it running through the turbo etc once the engine is turned off but I don't really know much about the coolant/heater system overall as I've never had to touch it. It's why I suggested getting the workshop manuals, you can have a look through and get all the info you need - they're really really handy to have.
Well yes the thermostat is in the same housing but I think you can change one or the other but it's a while since I looked - Edit: I've checked on ETKA and you can get both parts separately. You're right about where it is, right faff to change but do-able at home if you have the time and are handy enough - again workshop manual has all the details (some Youtube vids too, Golf R etc, they're handy to give an idea as to what's involved).
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Cheers again, I will check my printer can do that and try and download all the workshop manuals, I checked the original listing for the replacement waterpump and it definitely came with the temperature control module (posh for thermostat I'm guessing)
It should be listed as a printer on a Windows machine so given they allow you to print, bosh print to PDF
Yes, that's the thermostat, daft name for it but at least you know it's been done.
I located and swapped out the heater control solenoid valve today and I am over the moon to say my heaters are working again, it almost seems like a luxury having heat again lol, I'm definitely back in love with my S1, I feel a wheel re-furb and full valet coming
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Excellent news. Glad you got it sorted. For reference where is the valve? Easy to get to?I located and swapped out the heater control solenoid valve today and I am over the moon to say my heaters are working again, it almost seems like a luxury having heat again lol, I'm definitely back in love with my S1, I feel a wheel re-furb and full valet coming
The valve is on the right side of the engine but it's pretty well hidden. I removed the air box to gain access and uncoupled what I think was an intercooler hose, after that it was pretty easy but I'm definitely gonna look at a decent tool for removing the sprung hose clips in case of any future need for one, You cant see it in the pic but it is underneath the hose where you see a jubilee type clip
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Nice one, thanks. Worthwhile getting the tool if you're planning doing maintenance etc, I've had one of these for years, so much better than trying to make do with pliers and screwdrivers or whatever