Brain pick on fans (996)
Brain pick on fans (996)
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DanoS4

Original Poster:

869 posts

217 months

Sunday 8th October 2017
quotequote all
Hi All,

Noticed a couple of things recently that I need to get sorted. Car has been off the road for most of the Summer (!) whilst holidays and teaching my daughter to drive have taken over.

Some background first.
So I noticed 2 things:

1. AC not working - checked the front and it appears a condenser has failed (tell tale signs of leakage from a stone strike)

This has led to the system shutting down as all the gass has leaked out.
So, I've got a replacement and will refit today.
I can then get it pressure tested and refilled.

This may have affected my other issue -

2. noticed that the car (that has a LTT fitted, so should sit solidly on 80 degrees), crept up in standing traffic when I drove it last week. I noted that the driver's side fan hadn't kicked in.

Looking down, the ballast resistor looked like it had seen better days, so I've already soldered on a replacement working resistor.

But there's no change in temps.

As plan b, I've got a spare fan assembly (whole thing) so I can change that too whilst the bumper is off and I'm changing the AC.

HOWEVER, my question is regarding the fans - will the temporarily "non-operational" AC affect my fans operation for say, cooling the car?

Will I need to get the system working to gain high speed fan operation?

Car isn't being driven at the moment, so time isn't an issue. Just want to get it sorted.

Thanks in advance,

Dan

bgunn

1,822 posts

154 months

Sunday 8th October 2017
quotequote all
The cooling fans do come on at low speed all of the time whilst the A/C is on (when it's working - i.e. full of refrigerant), and I find that holds the temperature down. Otherwise it'll show towards the '0' of the 80 on the gauge before the cooling fans are pulled on by the engine management. I've never got it to get to 'high temp' and the full speed fans come on yet though.

My Boxster used to, but that was because the low speed fan didn't work on either side due to failed resistors so it was hunting in and out of very high temp and not really regulating the temperature properly. The engine bay fan used to come on frequently at that point, too.

Edited by bgunn on Sunday 8th October 11:43

DanoS4

Original Poster:

869 posts

217 months

Sunday 8th October 2017
quotequote all
Thanks for the reply. :-)

I've also got to replace the OTHER ac rad as it's leaking too! So once I get this done and get the car re-gassed, I'll see what's what with fans kicking in etc.

Interesting to know about your fans though - I *might* be being overly sensitive. But in my experience (after having a Hartech rebuild), one can NEVER be too overly sensitive when it comes to these cars!

Cheers,

Dan

edc

9,491 posts

274 months

Sunday 8th October 2017
quotequote all
Coolpartsuk on eBay for AC condenser about £43 delivered.

skinny

5,269 posts

258 months

Monday 9th October 2017
quotequote all
IME the high temp fans don't kick in until something around 100 deg C. Resistors will not affect high speed operation. However if they've gone then you won't get any low speed operation which normally happens with AC on, or at medium high temps, and should help avoid your temps going 'high speed fan ' high

Without low speed fans and stuck in traffic then your LTT won't make a difference to your temp as it'll be fully open but you just can't remove enough heat from the rads. Its only when you have more cooling capacity than heat input that the LTT makes a difference such as motorway cruising.

Edited by skinny on Monday 9th October 19:38


Edited by skinny on Monday 9th October 19:41

DanoS4

Original Poster:

869 posts

217 months

Monday 9th October 2017
quotequote all
That makes sense - I'm leaning towards a fubar'd fan.

Better replace it then smile

996TT02

3,341 posts

163 months

Monday 9th October 2017
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If your condensers rotted due to debris between them and the radiators - budget for radiators, too.

DanoS4

Original Poster:

869 posts

217 months

Tuesday 10th October 2017
quotequote all
That was my initial fear, but when I cleaned them out, I checked around the actual rads - the usual telltale spots (the corners etc), and there's nothing there THANKFULLY.
The rads are 95% clean - looks like the AC rads "took one for the team" biggrin