Omega Owners Forum

Chat Area => General Car Chat => Topic started by: tunnie on 29 March 2011, 15:46:50

Title: LPG Tank Condensation
Post by: tunnie on 29 March 2011, 15:46:50
Noticed other day when doing a run to supermarket there was condensation on the tank, it was a couple of days ago when it was really warm, the condensation went up to the level it was filled at looking at the level.

Not seen this before as I used to burn an entire tank in a day or two!

Assume this is just normal? The cold fuel/tank and the warm moisture in the boot?
Title: Re: LPG Tank Condensation
Post by: aaronjb on 29 March 2011, 16:04:44
It'd be normal if we were talking about a cylinder for a gas BBQ in hot weather.. so I'm going to take a stab in the dark and say it's pretty normal for an LPG tank in a car, too ;)

The liquid is pretty cold, warm damp air condenses on the (cold) cylinder - but where the vapour level in the tank starts the tank gets considerably warmer so no condensation..
Title: Re: LPG Tank Condensation
Post by: Crazycarzowner on 29 March 2011, 17:12:47
Perfectly normal, my Range Rover did the same (when the LPG was in there long enough). You will usually find it when the weather starts to get warmer. Most noticeable when you put it in from the pump. All I'd advise is make sure the water has somewhere to go & any rust is treated, I found it a little too late (made rusy hole on the underside of the car) mind you, nowt new of Range Rovers.  ::)
Title: Re: LPG Tank Condensation
Post by: tunnie on 29 March 2011, 17:14:44
Cheers all, thought it was normal.  :y
Title: Re: LPG Tank Condensation
Post by: Kevin Wood on 29 March 2011, 17:28:57
If you've filled cold liquid into a tank that is sitting in a warm, humid car interior it is indeed normal.

Once the liquid in the tank has reached the same temperature as the car interior it should dry out.

It's not quite the same as a conventional gas cylinder in that, in that case, you're drawing vapour from the tank, so the liquid in the tank is absorbing thermal energy from its' surroundings in order to provide the vapour. This process cools the tank below ambient temperature.

In a vehicle tank you're drawing liquid and vapourising it externally using heat from the cooling system so the tank isn't cooled. It might be if your pickup pipe has fallen off or is above the liquid level and you're actually drawing vapour, of course. I'd expect it to run poorly, if at all, though.

Kevin
Title: Re: LPG Tank Condensation
Post by: tunnie on 29 March 2011, 17:30:53
it had been filled up a few days previously, so it was still fairly full, only burnt off 75 miles worth.
Title: Re: LPG Tank Condensation
Post by: Kevin Wood on 29 March 2011, 17:35:49
Quote
it had been filled up a few days previously, so it was still fairly full, only burnt off 75 miles worth.

Had it got cold overnight, then the car interior warmed up relatively quickly, leaving a cold cylinder in a warm car perhaps?

Kevin
Title: Re: LPG Tank Condensation
Post by: tunnie on 29 March 2011, 19:47:31
Quote
Quote
it had been filled up a few days previously, so it was still fairly full, only burnt off 75 miles worth.

Had it got cold overnight, then the car interior warmed up relatively quickly, leaving a cold cylinder in a warm car perhaps?

Kevin

It was last week or so when we had really hot day but a cold night, think I went out to car about 2 or 3ish  :-/
Title: Re: LPG Tank Condensation
Post by: TheBoy on 29 March 2011, 19:50:15
Noticed mine had some condensation on earlier today, when I was putting the spare crank sensor back in the MV6...
Title: Re: LPG Tank Condensation
Post by: feeutfo on 29 March 2011, 23:47:57
Normal. As said. I had a look at a BRC on a 3.2 last week. tank was covered in condensation up to the level. It was a warm Ish day and the car had been parked up for a fortnight.
Title: Re: LPG Tank Condensation
Post by: feeutfo on 29 March 2011, 23:50:59
Never noticed it on my old donut though, but then it's got the spare wheel cover over it. 8-)