Pretty sure this is a huge mistake.
30 ton split system using existing 30 year old coils. All lines left in as well as accumulator. Txv's were replaced as well as liquid line solenoids. Suction line filter added and lines blown with nitrogen. How much left over oil in the system is acceptable? The coils had to stay I wish it could have been replaced. Holes were drilled in the traps and taps were added so oil could be drained and blown out with nitro. Thoughts and feelings? Unit is not fired off yet. I am thinking of removing accumulator, and flushing with a flush kit.
I STARTED WITH NOTHING, AND I STILL HAVE MOST OF IT!
Pretty sure this is a huge mistake.
You need to take a step back and think about this.
UNDER NO CIRCUMSTANCES START THIS UNIT UP WITH R410A.
None of the components will be rated for R410A and are likely to fail using R410A.
If you want to change out R22 then you need to change to a compatible refrigerant USING SIMILAR PRESSURES such as R417A R422D depending on size of unit.
This is an accident waiting to happen.
Recently did a conversion on two 20 ton units as the condensers needed replaced. Warned the customer not to do it turns out we were right chasing refrigerant leaks on the indoor coil that were not there when the conversion was done. Big mess
both ends of the system was tested for R-22 now its going to see and feel 410A oil is the least of your problems,rebraze all the lines and do a 1000PSI nitro test maybe tonnage has to be effected with the higher pressures in what could be considered a low pressure original install
"when in doubt...jump it out" http://www.youtube.com/watch?v=U1qEZHhJubY
Seems to me a lot of similar refrigerants to R22 are available. I would be seriously worried about the system not handling the higher pressures.
Your prep sounds good... however a refrigerant that both operates at similar pressures and uses mineral oil would be my choice.
Let us know how this works out.
GA-HVAC-Tech
Your comfort, Your way, Everyday!
GA's basic rules of home heating and AC upgrades:
*Installation is more important than the brand of equipment
*The duct system keeps the house comfortable; the equipment only heats and cools (and dehumidifies)
*The value of comfort, over the long term; leave economic choices behind!
Choose your contractor wisely!
I will say this job got dropped in my lap to wrap up and fire off. I have checked the majority of all the brazed joints and have a 450 psi test on it right now. I am just trying to make the best of a bad situation. I had heard there were some new schools of thought about actually leaving oil in the system. I am curious if anyone had done it. The job has to be fired of on Tuesday regardless of what I want, it is out of my hands.
I STARTED WITH NOTHING, AND I STILL HAVE MOST OF IT!
I haven't done a 22 to a 410a conversion using a unknown rated coil. But with that said, I have done conversions from a mineral to a POE refrigerant. From what you have said, I would skip the flush kit, but change the accumulator for good measure.
Why is there is an accumulator? And you only have one......is this a single lineset?
I tend to agree.The coil parameters are not even close between R-22 and 410. As far as accumulators goes, it needs to be resized for the change in refrigerant. Accumulators are inexpensive compared to compressors.These are the types of jobs that any good service company would love to chase. Lots of problems, and there is nothing like doing the job twice.
GA-HVAC-Tech
Your comfort, Your way, Everyday!
GA's basic rules of home heating and AC upgrades:
*Installation is more important than the brand of equipment
*The duct system keeps the house comfortable; the equipment only heats and cools (and dehumidifies)
*The value of comfort, over the long term; leave economic choices behind!
Choose your contractor wisely!
If you ask this question on the refrigeration forum, they will laugh at it. Because they have done it for years.
Look like you have done your home work on oil flushing. Let her ripe. How many SEER can you loose? This 30 tons comes off the factory with 9 SEER .
I agree with you about the accumulator.
this whole scenario goes against what alot of us have learned.. different pressures .. diff oils .. different manufacturing applications - for 410a .. poe oild tolerates NO OTHER oil .. between evap. acc. how can you be sure its all out before retrofitting? and whats the point of all this .. god forbid this thing goes byebye.. now you back to replacing EVERYTHING .. and at that point you have now costed yourself and customer way more money and time then if you just replaced it which.. like it said .. god forbid.. you may wind up doing neway.. how come i never hear if at all maybe slightly .. why NOONE uses 407c? i may post that question .. i know it fractionates but its what i keep reading is a perfect drop in for r22.. still uses poe i believe tho.. sorry to go off topic .. good luck and please post the result ..
I wonder about the R-407 also... given the pressures being very similar. MeThinks it is about the cost of refrigerant...
I hope it works... if not... Some sales guy and/or co guy(s) will be 'on the hook' so to say.
I do remember reading the OP is not the decision maker... rather the worker-bee... lets not crucify the worker for doing as he was told.
Please DO let us know what happens... THX!
GA-HVAC-Tech
Your comfort, Your way, Everyday!
GA's basic rules of home heating and AC upgrades:
*Installation is more important than the brand of equipment
*The duct system keeps the house comfortable; the equipment only heats and cools (and dehumidifies)
*The value of comfort, over the long term; leave economic choices behind!
Choose your contractor wisely!
it's up and running! cycling and doing just fine. I will keep you posted on how it lasts.
I STARTED WITH NOTHING, AND I STILL HAVE MOST OF IT!