Air conditioning problems

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Johnnytheknife
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Air conditioning problems

Postby Johnnytheknife » Thu Nov 14, 2013 7:45 pm

Hi all,

The ac in my NA8 has had issues since I've had the car. It's had an intermittent fault where it just won't turn on, but lately it's been turning on as expected.

The problem I'm having is that it seems to work fairly well so long as I'm doing a reasonable speed (60 plus). Under that, the air isn't all that cold. After the air con has been running for a while, if I get stuck in traffic for example and the speed is lower, the air warms up again, but the revs also start bouncing around between say 1000rpm and 2500 rpm with no accelerator input.

When the air con starts, I can sometimes hear a belt slip, and this is sometimes audible when making tight turns with the ac turned on (but not always)

My thinking is that I need to check the belt tension but, aside from that, what else should I be checking/doing?

SlugRacer
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Re: Air conditioning problems

Postby SlugRacer » Thu Nov 14, 2013 11:26 pm

You might have a faulty condenser fan if it only works when you are going at a reasonable speed (the condenser is getting enough air flow through it with out a fan working). Sounds like there could be multiple problems though

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Rolley
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Re: Air conditioning problems

Postby Rolley » Sat Nov 23, 2013 2:13 pm

SlugRacer from my experience this is generally a sign of the system being low on gas.
If the compressor is kicking in there is a little left in there, enought so that the system low pressure switch isn't triggered but not enough to get cold at lowere comp speeds. Belt tension would not really affect this.

I would be looking for a leak. Check all the connections on the system where pipes are joined or connected to the Condenser, Evaporator, Reciever drier, compressor or TX Valve there will be dirt and dust sticking to the oil that leaks out with the gas.

Also the condenser (in front of the radiator) can cop a rock or two so leaks can happen smack in the middle of it.

If there are leaks you will need to replace the o-ring at that connection or the compoanant leaking and have the system pulled down and regassed with the correct weight of gas ansd oil.

If the system has never been worked on being an NA it "may" be running R12 gas, I have found it easier to replace all of the orings and put in a new Reciever Drier when switching to the new R-134a as it can shrink existing orings causing more leaks and making you pay for gas twice...

Hope this helps.

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wassup
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Re: Air conditioning problems

Postby wassup » Sat Nov 23, 2013 4:54 pm

I agree with Rolley.

I had similar problems with the aircon starting off cold but then warming up. If it's R12 then the front left of the car behind the nose cone is where the dryer/ receiver is located and it has a viewing glass. When the aircon is running you should be able to see if there is any gas flowing.

If the condenser is engaging then it's likely low gas. With R12 you need to convert to R135. A new dryer, o rings and adapter for gas is required. It took my local workshop 3hours which included a leak test.

The system is back to frosty but alittle less so that before. Apparently R12 is fantastic but bad for the environment.
1990 NA6
Civic Type R

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MrRevhead
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Re: Air conditioning problems

Postby MrRevhead » Sat Nov 23, 2013 11:05 pm

An easier solution without converting the system while still achieving super cold R12 temps is just to refill/gas with hychill hr12/minus 30. The legal equivalent to R12.

I run it in my system, 5.8c vent temp after a regas. Many auto elecs will try and convince you to retro fit to r134a as they are not hychill stockists so shop around and reap the benefits.

If you're in Syd, PM me and I'll let you know who supplies HR12.

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1991 NA6 BRG Limited Edition #124 (Aus Delivered)
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Johnnytheknife
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Re: Air conditioning problems

Postby Johnnytheknife » Sun Nov 24, 2013 9:14 pm

Thanks all - the aircon has been regassed prior to me acquiring the vehicle. I think I'll take it to an AC shop and let them look at it. I've got no appetite for finding AC leaks.

danman
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Re: Air conditioning problems

Postby danman » Sun Feb 23, 2014 4:30 pm

Looks like we have the same problem in our NA8. It all fires up when it's turned on but no cold air comes out.

There seems to be some gas in the system (a technical check of pressing the Schroeder and feeling pressure). I'm thinking that there may be benefit in changing teh o-rings before I replace the gas. Where is a good place to get a seal kit?

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Rolley
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Re: Air conditioning problems

Postby Rolley » Fri Feb 28, 2014 6:36 am

There is not really a "Seal Kit" available as such.
The best way is to open all the joints and pull out the existing O-rings and take them down to Bursons/Repco and get them to just match them up.
You will probably find the original black rubber orings in there, make sure the new ones are made of the right material for the new gas you are going to get put in there. Nitrel (generally green in colour) are good for R134a. You will need to lube the O-Rings with compressor oil to ensure you get a good seal generally you can get enough oil out of one of the lines to wet them.

If you are going to that much trouble then definatly get a new reciever drier and install it with the new o-rings. (It is like a filter for the gas and oil in the system drawing out any moisture in the system.)

Luke.

khlmx5
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Re: Air conditioning problems

Postby khlmx5 » Wed Aug 27, 2014 5:32 pm

so have the problem been solved? can your share the solution with us?

I am asking because my stock na6 makes squealing noise with the air con on especially when car is cold. When i accelerate the car to higher rev the noise disappear and this repeats itself at start and stop.

If you have solution to similar problem please share with me. My car recently had a newer condenser installed with new gas before I purchased it.

Thanks :)

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SuperMazdaKart
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Re: Air conditioning problems

Postby SuperMazdaKart » Thu Aug 28, 2014 8:21 pm

Might need to adjust the belt tension.

When I had my NA6 I found getting a radiator top cover plate helped the A/C. Less air escaping through the gaps at the top instead of through the radiator/condenser. Later got a regas which helped more.

The A/C system is also meant to be used fortnightly for 10 minutes. Keeps the seals lubricated so they don't dry out & then crack. Causes an expensive repair bill. Lesson learned from my first car, something like a $1500 quote from an A/C specialist workshop. Half the cost of the car (88 Mazda 121 FunTop), unsurprisingly it didn't get fixed..
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khlmx5
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Re: Air conditioning problems

Postby khlmx5 » Fri Aug 29, 2014 7:25 am

Yes, u could be right . I ll chk out the belt. However, wud he noise come from the air con component at all? Yesterday i drove it again . After 20mins of driving the noise seem to disappear. It only haopens when the car is not fully warmed up. When the car is cold, rev during shift change helps to reduce or eliminate it

Johnnytheknife
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Re: Air conditioning problems

Postby Johnnytheknife » Tue Nov 18, 2014 10:50 pm

khlmx5 wrote:so have the problem been solved? can your share the solution with us?

I am asking because my stock na6 makes squealing noise with the air con on especially when car is cold. When i accelerate the car to higher rev the noise disappear and this repeats itself at start and stop.

If you have solution to similar problem please share with me. My car recently had a newer condenser installed with new gas before I purchased it.

Thanks :)

Kind of. The intermittent fault with it not turning on has become a permanent state. If I switch the relays using a jumper wire, the ac works fine. I believe the problem is actually with the fan switch which, in addition to turning on the blower, also sets a signal wire to ground which tells the ecu that the blower is turned on and the air con can be active.

My plan is to just wire in a relay off the supply to the blower which will set the signal wire to ground as I don't feel like dismantling the centre console to get to the switch.

I've just been short on time and motivation to fix it.


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