Discus Reeds

[Dowadudda]

Blown all to hell. How does one distinguish between if it was SLUG or High Heat based upon inspecting them only.

[engineerdave]

I'm not sure. Would think that heat would discolor the metal, while slugging would leave a mark......?

[HVAC9900]

If overheated, should have significant discolorisation, and probably sludge type build up on discharge side .Oil may be discolored too, depending on system size.
Slugging usually has severe mechanical damage.

[iceboxer449]

Were they the new style where the reeds are fixed or the old style where the reeds were removable. On the old style the reeds would wear an oval where they sat on the pins after time they would work loose and jam in the discharge valves. Other wise if they were blown that bad I would say it would be a oil or liq ref slug.

[Dowadudda]

This rack is 22, low temp, demand cooling. How many times you go on a rack like that and with out any evidence, your already prejudice that the oil is screwed, and what ever you find you quickly say, "yep heat, thats what did it"

I did, on this initial diagnosis ignoring my training. I had a bad bad valve plate, seen it 100 times. And I initially said heat was the culprit. For some reason, it just wasn;t sitting well with me, and I came home, referenced my notes, and had the "i could have had a V8 forehead slap to my temple"

And I know better. But it also shows the power of having knowledge and being humble enough to reference back, and recant yourself. So.

Those 2 very different conclusions could lead you on a goose chase and a another failure. Reference. Reference. Reference. I don't tell anyone "i know". I say give me a minute and I will find the right answer.

[gatorfan9606]

i have seen the reeds with a slight bend to them around the oval part thats slug discolor is high temp oil starts to smell

[Freezeking2000]

This rack is 22, low temp, demand cooling. How many times you go on a rack like that and with out any evidence, your already prejudice that the oil is screwed, and what ever you find you quickly say, "yep heat, thats what did it"

I did, on this initial diagnosis ignoring my training. I had a bad bad valve plate, seen it 100 times. And I initially said heat was the culprit. For some reason, it just wasn;t sitting well with me, and I came home, referenced my notes, and had the "i could have had a V8 forehead slap to my temple"

And I know better. But it also shows the power of having knowledge and being humble enough to reference back, and recant yourself. So.

Those 2 very different conclusions could lead you on a goose chase and a another failure. Reference. Reference. Reference. I don't tell anyone "i know". I say give me a minute and I will find the right answer.

Gas defrost? = slug

[gatorfan9606]

This rack is 22, low temp, demand cooling. How many times you go on a rack like that and with out any evidence, your already prejudice that the oil is screwed, and what ever you find you quickly say, "yep heat, thats what did it"

I did, on this initial diagnosis ignoring my training. I had a bad bad valve plate, seen it 100 times. And I initially said heat was the culprit. For some reason, it just wasn;t sitting well with me, and I came home, referenced my notes, and had the "i could have had a V8 forehead slap to my temple"

And I know better. But it also shows the power of having knowledge and being humble enough to reference back, and recant yourself. So.

Those 2 very different conclusions could lead you on a goose chase and a another failure. Reference. Reference. Reference. I don't tell anyone "i know". I say give me a minute and I will find the right answer.

hussmann rack with the epic controller?

[gatorfan9606]

short cycling can cause the reeds to disappear

[iceboxer449]

Low temp 22 with demand cooling. I have had major problems with the white teflon seat in the demand cooling valve holding the valve open. It then proceeds to blow out the reeds. If you are not having oil failure trips which are so common with low temp r-22 I would consider this possibility.

[crackertech]

Low temp 22 with demand cooling. I have had major problems with the white teflon seat in the demand cooling valve holding the valve open. It then proceeds to blow out the reeds. If you are not having oil failure trips which are so common with low temp r-22 I would consider this possibility.

We service lot's of low temp R-22 racks and have few oil failure's due to the fact that we do a pm once a month and change the oil and filter(or add one)
once a year.

[iceboxer449]

Yea, customer wants to wait till friday at midnight to agree to oil change. Also the inhouse maint does not check sump screens because " oil float is full " usually find them sucked closed and begging to be cleaned or changed.

[jpsmith1cm]

We service lot's of low temp R-22 racks and have few oil failure's due to the fact that we do a pm once a month and change the oil and filter(or add one)
once a year.

We do this and still have a fair number of trips.

Too many techs don't like to see ice on the suction lines.

"It was flooding back, so I closed all the TXVs." :eek:

Dumba$$

[jpsmith1cm]

To answer the original question, with a slug, I would expect a lot more than just broken valves. Damage to pistons, connecting rods, etc.

[crackertech]

Too many techs don't like to see ice on the suction lines.

"It was flooding back, so I closed all the TXVs."

Dumba$$ Hey I know those techs.:eek::eek::D:D

[jpsmith1cm]

They work for you, too?

I thought that I had all of them up here....

:D

[Dowadudda]

To answer the original question, with a slug, I would expect a lot more than just broken valves. Damage to pistons, connecting rods, etc.

looking at copelands' explanation of compressor damage, reed damage is due to slug.