Xarios 200

[djbean]

Hi all. I'm very new to refrigeration engineering and am cutting my teeth on a faulty Xarios 200 (with standby compressor) system (R404a) fitted into a transit van.

The system will not run for more than a few moments without tripping out on a LP swith (error code A001).
The sight glass is showing 'wet' indicator.

I suspect icing of the expansion valve and applying a little heat does get it going again for a short while.

I decided to recover the refrigerant, vac, replace dryer and recharge. However I cannot seem to recover all the refrigerant.

I am unsure of the usual procedure for this kind of system but assumed it should be no different to usual. I connected the manifold gauges to the service ports and connected up to the reovery machine. I was only able to recover about 0.4 kg of the expected 1.4kg charge.

I am wondering if there is a blockage at the expansion valve that would prevent complete recovery from the LP side. Tracing the refrigeration circuit I see there are check valves between the HP service port and the condenser, so I am assuming that I cannot fully recover the charge through the HP service port.

Would anyone have any thoughts on my diagnosis so far and can anyone suggest how I can fully recover the charge?

Additionally I have the Xarios 150/250 operators manual which details a maintenance schedule. I feel it would be appropriate to replace the compressor oil but have no idea how I would do this. Does anyone know?

Thanks in advance for any help.

[clivemtk]

take off condenser cover locate two soleniod valves valve with big coil is closing valve and has a red collar on it the smaller one being a hot gas valve remove it and fit a coil magnet and watch gas come back reply

[djbean]

Thanks for quick response clivemtk. I had tried opening this valve with solenoid magnet. It made very little difference, which was why I traced out the whole circuit. Thats when I figured the check valves would prevent much coming back via the HP service valve. Sorry, should have mentioned that in the original post -but I thought it was getting too long :)

[djbe]

Hi all. I'm very new to refrigeration engineering and am cutting my teeth on a faulty Xarios 200 (with standby compressor) system (R404a) fitted into a transit van.

The system will not run for more than a few moments without tripping out on a LP swith (error code A001).
The sight glass is showing 'wet' indicator.

I suspect icing of the expansion valve and applying a little heat does get it going again for a short while.

I decided to recover the refrigerant, vac, replace dryer and recharge. However I cannot seem to recover all the refrigerant.

I am unsure of the usual procedure for this kind of system but assumed it should be no different to usual. I connected the manifold gauges to the service ports and connected up to the reovery machine. I was only able to recover about 0.4 kg of the expected 1.4kg charge.

I am wondering if there is a blockage at the expansion valve that would prevent complete recovery from the LP side. Tracing the refrigeration circuit I see there are check valves between the HP service port and the condenser, so I am assuming that I cannot fully recover the charge through the HP service port.

Would anyone have any thoughts on my diagnosis so far and can anyone suggest how I can fully recover the charge?

Additionally I have the Xarios 150/250 operators manual which details a maintenance schedule. I feel it would be appropriate to replace the compressor oil but have no idea how I would do this. Does anyone know?

Thanks in advance for any help.


Hi,

Your diagnosis as far as moisture being in the system is probably spot on, you will find that a Xarios of a certain age will have this problem. A drier change and vac will cure it for a while but it will come back again how soon seems to depend on if the unit is running frozen or chill.

A longer term fix usually involves replacing the flexible hoses and fittings.

As for recovering the refrigerant has the unit got a liquid receiver? There should be an access port on there which will allow you to pull refrigerant from the high side?

As for replacing the compressor oil are you referring to the road or standby compressor (if it has one).

Regards,
djbe.

[radekklimat]

If the sight glass is a yellow gas that is certainly moist and is not suitable for reuse.
It should spin the expansion valve, clean the nozzles
Flush the entire system petroleum ether
Blot dry with nitrogen [blow], replace filter, refill with fresh oil to the bottom of the compressor [250 ml], pull a vacuum of at least daily, clean fill, a new factor.
As for the review of oil is not mentioned in these compressors unless there is a suspicion of moisture, it just does not practice anything like that.

[djbean]

Thanks again for responses.
The unit is running frozen and is 7 years old.
I have finally managed to recover the charge at 1.39kg. Didn't have the response about the access port on the receiver which, now that I look at the diagram I traced out, makes sense and would have recovered up to the check valve at end of flexible hose going into evap unit.
I managed it by running up the unit, which again cut out on LP (as, I assume the TXV blocked). I applied heat onto the valve until pressure came back up a little, then switched of the unit. Kepp gentle heat on the TXV while started recovery and it all came out. :)
Regarding the oil change, the manual I have states changing compressor oil every 2000 running hours. It doesn't say for which compressor but I think it's safe to assume it's the road compressor as this is the one that is mostly in use.
I'm still not clear on how to change it though. How to get it out, how to get it in or how much to replace it with.
The original intsallation diagram does however show an icon of an oil can with arrow pointing to what I think is the hot gas pipe on the condenser unit. Still doesn't explain how to 'change' the oil as per the maintenance schedule details though.
Again thanks for all your help.

[djbe]

The only "easy" way to change the oil is to take the road compressor off.

You will find a drain plug in the base of the head below where the suction and discharge ports are. The compressor should have a filler plug on top of the body.

You should normally measure the amount of oil that you take out and put the same amount back in. But I'd reserve judgement on that until you find out exactly how much you take out.

There should be a sticker on the back of the compressor (if it is a seltec) which will say the model number and may indicate the oil charge.

[clivemtk]

have u cleaned the oriface filter in the expansion valve

[djbean]

have u cleaned the oriface filter in the expansion valve
err no!

Forgive me for asking but how do I do that? Do I dismantel the TXV at the point where I'd adjust for superheat, or do I need to remove the valve completely?

Appologies if this sounds like a stupid question - but this is my first time on a 'real' system.

[Clk320_Greg]

Ah bloody hell!!

We have had 4 of thes units mess around in the last 6 months, every time its been cured by a recover, drier change, long vac and regas!!

Frankly it baffled me as to what the hell was going on. but glad to see its common! Any idea as to where the moisture gets into the system???

[djbean]

I'm baffled on how moisture gets in as well since the system in pressurised.

[cadwaladr]

I'm baffled on how moisture gets in as well since the system in pressurised.shaft seal i guess

[djbe]

It seems to be related to the flexible hose and fittings.

I don't know how the moisture gets in but the only sure (long term) fix seems to be repipe the thing.

Carrier have recently moved to a different pipe, perhaps this is a cure?

[vtmpnate]

Just take the valve down and remove the filter from the liquid inlet.


err no!

Forgive me for asking but how do I do that? Do I dismantel the TXV at the point where I'd adjust for superheat, or do I need to remove the valve completely?

Appologies if this sounds like a stupid question - but this is my first time on a 'real' system.

[djbean]

All up and running ok again.

Thanks to everyone for help and advice.

[djbe]

All up and running ok again.

Thanks to everyone for help and advice.

Glad you got it sorted.

regards,
djbe.