BX Air conditioning R134A conversion (all you need to know thread)

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Jaba
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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by Jaba »

Aaah I get it now. This is normal behaviour with the blower motors on high speed because you are blowing air through the evaporator at a higher rate than the aircon system can cool sufficiently so the compressor will be on permanently to try and provide enough cooling.
You might be getting low on refrigerant as this will reduce the aircon performance. Have you had it recharged recently ?
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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by senmathal »

Maybe it´s my explanation that is odd :) What do you mean sounds odd? What I mean is that the high speed only com on when I short circuit the pressure switch but not when I run the A/C.

/Mats

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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by Jaba »

senmathal wrote:
Thu Jul 20, 2017 8:47 am
Maybe it´s my explanation that is odd :) What do you mean sounds odd? What I mean is that the high speed only com on when I short circuit the pressure switch but not when I run the A/C.

/Mats

Yes, I have got that now.
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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by senmathal »

Sorry I did not see your last answer when I did my reply. Yes I have recently have my A/C charged. But it has not been in use fore a couple of year so maybe it´s a leakage somewhere in the system. I think I will take it to the garage and looked at it with ultra violet light. But it´s still very cold air blowing and it´s work properly. Maybe the cooling fan will get in high speed a hot day. As I understand the pressure will rise when the system get hotter. Sadly this summer in Sweden seems to be the coldest summer in many year.

/Mats

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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by white exec »

Conversion to R134a
O-rings

Have just taken delivery from Citroen of the four sizes of pipework O-rings, and run a vernier over them.
The dimensions might be useful in the future, should the items go NFP/difficult to source.

part no ¦ Int.∅ parts listing ¦ int.∅ × thickness, measured
6460 CR ¦ 14 ¦ 14.0 × 1.80
6460 V0 ¦ 10.82 ¦ 10.8 × 1.80
6460 C2 ¦ not stated ¦ 8.75 × 1.80
6460 T9 ¦ 7.65 ¦ 7.60 × 1.80

All of these are used on a huge range of Citroen vehicles, right up to Aircross and Cactus.
Last edited by white exec on Sat Apr 24, 2021 10:01 am, edited 2 times in total.
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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by white exec »

.
Conversion from R12 to R134a — Citroen documents

While browsing servicebox Parts for something quite unrelated, I found these four Service Documents.
They are detailed conversion instructions for converting from R12 to R134a — for AX, BX and CX.

By simply going into BX parts (not repair procedures, which I don't have a subscription for), and doing a Search for "blanking" (which is what I was looking for), you get this:
.
click to enlarge
AC conversion - Parts page, listing documents.JPG
.
The last four items are on-screen PDFs (which can be printed or saved), are are:
.
1 - Cleaning - air conditioning circuit
2 - Oil drainage - air conditioning compressor and dehydrator
3 - Conversion of air conditioning (up to RPO 3341)
4 - Conversion of air conditioning, single A/C, for RPO 3341→
.
The full documents are available to ServiceBox subscribers, via the page above.

EDIT
Don't get excited over this. There was/is obviously a bug in the SB system that intermittently allows some access to documentation, even when a subscription doesn't cover that. Most of the time, the site works normally.
Chris
Last edited by white exec on Sat May 01, 2021 10:07 pm, edited 6 times in total.
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Re: BX Air conditioning R134A conversion (all you need to know thread)

Post by white exec »

BX etc Pressostat
Advice in the Cit documents is to replace with an updated one, because of the different operating temperatures of compressed R134a.

Original Cit pt.no. listed as 95 496 899, now NFP.
6455T2 replaces it, and is fitted to a string of PSA vehicles.

6455T2 also appears on Mister Auto - choice of half-a-dozen makes.
It's a triple pressure sensor. One spec reads:
<2 bar OFF [no gas]
>26 bar OFF [over-pressure]
17 bar ON [normal wkg pressure; replaces the earlier 19 bar]
Chris