Air con

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Gibbo2286
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Air con

Post by Gibbo2286 »

Had the C5 air con re-gassed three weeks ago and it's failed again, can't see any obvious leaks, anyone tried those STP leaks sealers?

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moizeau
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Re: Air con

Post by moizeau »

No, wouldn't trust it, if it stops a leaks it will also block other orifices, get a UV dye added and find the leak or live without AC

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white exec
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Re: Air con

Post by white exec »

Second that. Get it professionally leak tested, either by UV or sniffer detection, whichever the specialist recommends.

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Re: Air con

Post by Gibbo2286 »

I just saw it recommended and thought I'd ask if anyone had tried it. I'll get the local lot who re-gassed it to check it out, may already have the dye in the system, too hot out there to do much today, car's in full sun all day.

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white exec
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Re: Air con

Post by white exec »

If it already has the UV tracer dye in the system (or will have), you can get one of the small UV torches from Amazon.
Go for the 365nm type for best visibility, 3W or 5W.
Have recently bought one for use here, while resurrecting the BX's system.

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Re: Air con

Post by Gibbo2286 »

I think I already have a uv lamp here somewhere, just need a cooler day to go do the business. :)

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Paul-R
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Re: Air con

Post by Paul-R »

Most A/C refillers can only perform a vacuum test on the system to try to find a leak. Only the specialist ones will offer a pressurising test and, unsurprisingly, these type charge more.

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GiveMeABreak
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Re: Air con

Post by GiveMeABreak »

I've had the C3 pressure tested, leak checked, serviced (vacuumed out, disinfected, recharged with gas and appropriate oil) all for £70 and that was a mobile service - perfect job.

But don't put any leak sealers into the system - reason being their job is to find any air - when it does it solidifies into a gunk - result if you have any air in the system it causes blockages and on-going expense to repair.

Always better to fault find and repair - not a quick fix that could cost more longterm.

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white exec
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Re: Air con

Post by white exec »

Absolutely second that. Nothing claggy must go into the system. The easiest bit to block up is the expansion valve (TXV) which finely sprays liquid refrigerant into the heater unit's evaporator, and the dryer acts as a fine filter too.

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Re: Air con

Post by Subsonicnat »

Amen to bodging the system with any form of sealer..
Do have aproblem, Tried the dye and bought a Sniffer ,,could not find a leak anywhere.??.
Running ok on pressures,,,but stillnot cold... I know very little about A/C but could someone explain the valveon the bulkhead,,??.. It could possibly be that or a Pump failing ,Any ideas..
I like the thread about home visit A/C fixing but where does he reside thats the problem.
Lucky finding him mate.. not to bad a price either..

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white exec
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Re: Air con

Post by white exec »

My recent experience was of a compressor that was pumping (doing work, getting hot, and also warming the pump's output pipework at the condenser) but no cooling of the cabin. This was a blockage of the TXV (thermal expansion valve) on the cabin side of the bulkhead (and attached to the evaporator of the heater unit). Replaced the TXV, and all then worked. The other component that comes before the TXV is the dryer/dehydrator, but that is unlikely to block, just fail to dry.

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Re: Air con

Post by Subsonicnat »

Thank you very much"White exec" for your speedy Reply..
Can you Replace the valve with out taking the dash out as it does seem horrendous to do.
I don't know if you know my car is a Xsara picasso 2.0HDI 2004.
Would you please advise as to how to replace it,, keeping fingers crossed.lol.
Colin.

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white exec
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Re: Air con

Post by white exec »

Have only done the job once, Colin, very recently on our BX. Access made extra awkward by the car being LHD, so pedals and steering column nicely in the way.

Someone here will know the Xsara Pic' better, and can advise on the procedure.
You might needs some parts/components info, so maybe a good time to do a Parts inquiry donation to the forum.

My replacement TXV was around €40 from Mister Auto.
Make sure it comes with its O-rings, if the type that uses them.
New O-rings/seals needed for any other pipework that you need to disconnect. Parts should have details of these.

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Re: Air con

Post by Subsonicnat »

Thank you very much Chris,,Sounds like you were getting stuck in under the dash.lol.
if there is anyone on here who has a Xsara picasso who have replced the tx valve on said car.
Couldyou please advise as to the procedure, "Do You Have toTake the Dash apart".
Colin.