No A/C; how to know if I need recharge
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No A/C; how to know if I need recharge
Just lost air conditioning with no warning lights, noises from engine, or signs of
leaks under car, so can I get some advice on this ?
How do I know if I need more coolant for air conditioner ? A recharge ?
leaks under car, so can I get some advice on this ?
How do I know if I need more coolant for air conditioner ? A recharge ?
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Joined: Sep 2012
Posts: 55
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First off - good call on asking questions BEFORE jumping the gun and squirting in a bunch of cans of refrigerant. However, we're starting diagnostics with very little to go on. Is the compressor clutch engaging? It's probably hard to see in the engine compartment. Can you see the compressor face turning (not just the pulley, which will always be turning whenever the engine is running)
If the compressor clutch is NOT engaging, we have to troubleshoot that, and the rest of the refrigeration setup is potentially just fine. If it IS engaging, then we need further information, for which you'll need to purchase an A/C gauge set (AKA manifold gauge set.), and hook it up to the low pressure and high pressure service ports on the car. The low pressure port is on the A/C line directly underneath the power steering fluid reservoir. The high pressure port is right on the front of the engine compartment. Both ports have black caps on them that have to be unscrewed. IIRC, one takes a 19mm socket, and the other a 22, 23, or 24 mm socket (forget which). On these Volvos, the high pressure port is recessed, so you may need the Volvo high side service port adapter
Even if the clutch is NOT engaging, we may still need the gauge set, depending on where the initial diagnostics take us...
Whatever you do, DO NOT PUT IN ANY CANS OF REFRIGERANT CONTAINING LEAK SEALER!!!
Not to jump to conclusions here, but a very common reason (but not the only one) for sudden loss of cooling (especially during the hot summer months) is excessive compressor clutch gap. The general symptoms are that when the engine is cool, the clutch engages and you have good cooling. As the engine warms up, and especially on hotter days, the clutch will drop out and fail to re-engage, so you have sudden loss of cooling performance when you need it most. So pay attention to the if/when you have cooling (if it comes back at all), to see if it matches these symptoms. If the symptoms match, you can further verify this theory: On a hot day with the engine warmed up, A/C on high, but the compressor not engaging, give the compressor clutch a light tap with a small hammer (if you can do so safely with the engine running) to see if the compressor suddenly engages. If it engages, then it means that excessive clutch gap is the culprit.
If the compressor clutch is NOT engaging, we have to troubleshoot that, and the rest of the refrigeration setup is potentially just fine. If it IS engaging, then we need further information, for which you'll need to purchase an A/C gauge set (AKA manifold gauge set.), and hook it up to the low pressure and high pressure service ports on the car. The low pressure port is on the A/C line directly underneath the power steering fluid reservoir. The high pressure port is right on the front of the engine compartment. Both ports have black caps on them that have to be unscrewed. IIRC, one takes a 19mm socket, and the other a 22, 23, or 24 mm socket (forget which). On these Volvos, the high pressure port is recessed, so you may need the Volvo high side service port adapter
Even if the clutch is NOT engaging, we may still need the gauge set, depending on where the initial diagnostics take us...
Whatever you do, DO NOT PUT IN ANY CANS OF REFRIGERANT CONTAINING LEAK SEALER!!!
Not to jump to conclusions here, but a very common reason (but not the only one) for sudden loss of cooling (especially during the hot summer months) is excessive compressor clutch gap. The general symptoms are that when the engine is cool, the clutch engages and you have good cooling. As the engine warms up, and especially on hotter days, the clutch will drop out and fail to re-engage, so you have sudden loss of cooling performance when you need it most. So pay attention to the if/when you have cooling (if it comes back at all), to see if it matches these symptoms. If the symptoms match, you can further verify this theory: On a hot day with the engine warmed up, A/C on high, but the compressor not engaging, give the compressor clutch a light tap with a small hammer (if you can do so safely with the engine running) to see if the compressor suddenly engages. If it engages, then it means that excessive clutch gap is the culprit.
Last edited by webbch; Jun 20, 2014 at 01:52 AM.
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I found out later on that if we select "manual" on the circulation button and select "on" at the air conditioning button ; then we we get our cool air temp back in car.
The "auto" button seems to be a problematic in getting cool temps from the air conditioner.
I will save the reply info you so kindly offered.thanks !!
The "auto" button seems to be a problematic in getting cool temps from the air conditioner.
I will save the reply info you so kindly offered.thanks !!
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Joined: Sep 2012
Posts: 55
Likes: 1
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