Carrier 48TJE016 610QA 4195F73654

[Milk man]

Changed out the condenser coil today. Coil had a leak. The desiccant started falling out of the dryer’s inlet. Didn't look like it was coming from the outlet. We installed a new drier and weighed in the refrigerant plus one pound:

Compressor loaded,

Head was 210 psig with 14 degrees SC
Back was 33 psig with zero degrees SH
No delta T across the drier or LLS
All inlet orifices to the evap where frosting
Some return elbows where wet some where dry
Top half of suction header was 72 degrees
Bottom half of suction header was frosted
Good airflow with tight belt
Fire dampers open.
Bottom two row of evap frosted
Compressor cut off due to freeze stat on evap
Unit equalizes after unit satisfies.

I think some of the orifices are restricted and the liquid is being forced through the others and not boiling off in the evap

[svc]

with all metering devices(i think theres 6 )frosting,low suction and no superheat it sounds like an air flow problem .How did you check airflow? suction header?

[Edited by svc on 08-30-2004 at 11:01 PM]

[Dad]

Lynn,


Had the same problem with same readings in a carrier rtu this July. I had 11 accutrol metering devices and 5 were frosting. It was easy to get a TXV and distributor and replace the orifices. Just cut the liquid header out. Be sure to build the spider and TXV before you get to the job. Makes it sooo much easier.

[mardoman]

I to have had "Carrier Constipation".
With so many Mfgs. advising using quality filter driers for compressor replacement etc.,you would think Carrier would take their own advice and quit using those Freaking spun molecular sieve strainer/driers that keep blowing out.

You may want to try de-energizing condenser fan and raise the head pressure to about 350 psig to see if the obstuctions pass.

Another try would be to recover the charge and cut loose liquid line and blow nitrogen back thru suction and try to catch the contaminants with a clean towel. You will probably see Carrier's patented "green" oil. Whats up with that?


The latter is time consuming. Face it, you have a restriction and will have to replace the metering devices or put in a TXV.

While your at it, please make sure the IDB motor is turning correctly and you wash and degrease the evap and condenser.

Don't be suprised if the "Carrier" wholesaler has never heard of this before and has a hard time finding the "header assembly" for your unit. They make you feel like your the only one in the world that this has happened to.

[plain spoken]

Carrier stopped using the strainer and started using a drier in 2000. The headers are listed in the EPIC parts database so it should not be a problem to locate.

[Milk man]

Passed this along to the other guy that went back today. He was working on it late so I don't know anything.

[svc]

Im confused how you have 0 superheat if your suction pressure is 33 and your header temp is 72. What is the temp @ compressor suction line. with a restriction @ your orifices you would have a high superheat. what is your static? whats the ambient?

[Edited by svc on 08-31-2004 at 08:14 PM]

[Milk man]

Originally posted by svc
Im confused how you have 0 superheat if your suction pressure is 33 and your header temp is 72. What is the temp @ compressor suction line. with a restriction @ your orifices you would have a high superheat. what is your static? whats the ambient?

[Edited by svc on 08-31-2004 at 08:14 PM]

The suction header is about 20 inches long. In the middle is where the suction line goes back to the compressor. The top half of the suction header was 72 degrees and dry. the bottom half is frosted up the suction line and back to the compressor.

[rob williams]

I realize this thread is a tad bit old, but I wanted to ask, how do you cut the Accutrol Header out of the system for replacement? It is VERY tight inside the unit. I cannot get an imp tubing cutter inside, so I hope someone answers this for me.

Thanks
Rob