Normal for A/C to make car engine run louder and have less Oomph?

Soldato
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Afternoon guys! ;)

My dad just got his car back recently after being involved in an accident. I've read mixed reports about the repairers. Anyway...

Today when I was driving it home from work, I noticed that there wasn't much power under acceleration when the A/C was on and the car seemed a tad noisier than usual. I don't recall the A/C being on affecting performance that much pre-accident but I can't be sure. It seems to up the engine revs slightly and run generally louder even when idle. The louder operating sound isn't really something I recall before. Is this normal (and am I imagining things) or do you think there might a problem brewing?

Many thanks.
 
Was the A/C touched in anyway during repairs, as they may of overcharged the system with refrigerant.
 
How big is the engine, small engine = more of a drain from the AC.
 
yeah take it back to um,, having the AC on is a slight drain,, but only very slight, i carnt say i notice any diff in performance with mine on
 
Was the A/C touched in anyway during repairs, as they may of overcharged the system with refrigerant.

The entire front of the car was smashed in including the radiator so I'm guessing... The engine itself escaped being wrecked somehow but I don't know much about cars unfortunately. Is it likely the A/C would have been touched?

How big is the engine, small engine = more of a drain from the AC.

Vauxhall Astra Design 1.6 2008
 
Usually the A/C is infront of the car, and around the rad, so its very likely it would have been. You sure you are not just noticing it more? It does happen since you are listening out for anything that may not be right. My car doesn;t accellerate quite as well with the AC on, but then, its a 1.4.
 
Your going to feel something with it on in a 1.6.

Take it for a second opinion somewhere else if you are concerned though.
 
The entire front of the car was smashed in including the radiator so I'm guessing... The engine itself escaped being wrecked somehow but I don't know much about cars unfortunately. Is it likely the A/C would have been touched?

I would have though they have installed a new condenser, but they may of screwed up the charging of system, ie not vacced the system out and you may have non condensables in the system.

But I would return the car and let them have a look, There might some other damage else were.
 
It's definitely not right. I was just outside again and turned it on and the sound cranked right up. It's like a jet now. Video coming...
 
I would have though they have installed a new condenser, but they may of screwed up the charging of system, ie not vacced the system out and you may have non condensables in the system.

But I would return the car and let them have a look, There might some other damage else were.

AC systems have a dual pressure switch, overfill generally would cause excessive pressure and system shutdown.

Typically cars will automatically disengage the ac when the engine is under high load or wide open throttle.

It's normal for the idle rpm to be up a little.
 
AC systems have a dual pressure switch, overfill generally would cause excessive pressure and system shutdown.

Typically cars will automatically disengage the ac when the engine is under high load or wide open throttle.

It's normal for the idle rpm to be up a little.

It depends on what the HP switch is set to, it may be running just below the HP cut out and is the switch operation ok, in some cases the pressure switch is on the liquid side and you get a pressure drop across the condenser so the vapour side could be higher.
 
Sounds like the cooling fans have gone into overdrive, think best bet is to return it to the garage and let them have a look.
 
if you got twin fans, one of the fans should run all the time when the a/c is on, But if one of the fans die then it resorts to just one fan and they can sound exactly like the above going into hyper drive :D
 
Vauxhall is a mystery to me but I know Nissan systems. Rad fan runs constantly on low speed while AC is on, if water temp rises then fan goes to high speed.
Is that fan running when the AC is off?
 
Vauxhall is a mystery to me but I know Nissan systems. Rad fan runs constantly on low speed while AC is on, if water temp rises then fan goes to high speed.
Is that fan running when the AC is off?

Well the A/C gets turned on at the 0.06 in the video. Anything before is just general car fan noise.
 
Sounds like the cooling fans have gone into overdrive, think best bet is to return it to the garage and let them have a look.

I've just emailed them as I'm busy on Monday and they're now closed. They better repair it free of charge or they'll wish they had! :(

if you got twin fans, one of the fans should run all the time when the a/c is on, But if one of the fans die then it resorts to just one fan and they can sound exactly like the above going into hyper drive :D

I really don't know if it's two or just the one we have...
 
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