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View Full Version : Oops moment... think I can fix, need clarification, advice, resource suggestions



TimH
08-09-2011, 08:14 PM
Ok, so everyone leave your ideas about conspiracy theories at the login page for this one....

I have begun a relentless pursuit towards understanding anything electrical, mechanical, thermodynamic and fluid dynamic... basically all things physics.

It all started because of a book and a documentary regarding the Peak Oil Theory... This theory scares me. To give myself more confidence that I would be able to provide a standard of living that is close to what we have come to expect, I have set out to prove to myself that I can demonstrate the understanding I am gaining through my self study and research of the things that make our lives easier through manageable, proof-of-concept projects that force me to design & fabricate working models of the devices, appliances, and components that make those things work out of, basically, free stuff or from components, tools commonly found in old or used devices, appliances etc.

Long story short, my first project has been to put together a portable 120v air conditioner that is, at most, efficient enough to cool 1 or two rooms.

The big picture components are:
- Entire refrigeration system (Compressor, condenser, evaporator valve, evaporator coil) from a Brita water cooler left out by my neighbor for heavy trash
- Computer tower box/enclosure
- 3 Electric fans ranging from 45-65cfm
- 1 homemade Dyson bladeless-style ("Air Multiplier") fan
- Electronic components from water cooler and pc tower (2 thermistors, 3 potentiometers
- AC-DC adapter from something 120v AC - 12v DC
- Purchased components - 120V relay, terminals etc.

I've laid everything out, "rigged" it together and tested the design for the power and operating controls and everything worked great. Then I started (too hastily) removing the thin reinforcing rods soldered to the front and back of the vertically snaked condenser coil... And yes, when prying one of the rods from its solder joint, I pulled it off and sprung a leak. In hindsight I realized how STUPID it was to do that. My questions are:

Why didn't my finger freeze off when I stopped it with my thumb (I could feel the pressurized gas coming out of the pinhole but it did not feel the slightest bit cold)?

How long will 5 layers of wound duct tape, 2 zip ties on each side of the hole and a hose clamp around the hole hold out as long as I don't run the compressor?

How do I fix the hole and get the system safe enough to run again? Or, a more liability-friendly way to put it for those EPA-regulation-minded individuals out there, could you provide a detailed explanation of how you, or other certified HVAC professional (if you get my drift) would remedy the system and have it back to pre-oops status?

Tech Specs from Stamp on Compressor:

Manufacturer: Matsu****a Refrigeration
Model: SB24C50GAU6
115V AC - Locked rotor (what's special about that?)
1PH R134a (I'm assuming this is the refrigerant and volume/quantity accept there is a big "22" inked stamped on the dome of the compressor, R22?"
Thermally protected

I've have a technical specifications book with all the formulas so I'm mainly interested in understanding the process for fixing the leak. My hunch is I'm most likely going to hear that I have to capture, weld, vacuum and recharge--details please--but I figure it might be such a small system (i.e. low enough pressure on the high side) that a solder or polymer of some kind will be a long term solution.

Thanks,

Tim

TimH
08-09-2011, 08:17 PM
Wow, that is hilarious. Manufacturer: Matsu****su ---- A.K.A. M-a-t-s-u-s-h-i-t-s-u

install monkey
08-09-2011, 08:37 PM
locked rotor- is the maximum current the compressor will draw if the compressor is siezed.
the 22 stamped on the top of the compressor is probably the person who inspected it when it was manufactured.
the sticker/nameplate will mention the refrigerant type and the application,hbp high back pressure(usually fridges)
mbp medium back pressure( for fanned evap on freezer) lbp low back pressure for plate evaps on chest freezers.
as to your repair-it will not last,if the cond coil is steel tubed then req degassing(if it hasnt leaked already) brazing with silver solder and flux,if copper then a brazing rod only. but beware you will damage aluminium fins in doing this repair!
best to get a techie to do this as you are not experienced with floro carbons , flammable oil and phosgene,also they can give advice regarding ur invention.
Ok, so everyone leave your ideas about conspiracy theories at the login page for this one....

I have begun a relentless pursuit towards understanding anything electrical, mechanical, thermodynamic and fluid dynamic... basically all things physics.

It all started because of a book and a documentary regarding the Peak Oil Theory... This theory scares me. To give myself more confidence that I would be able to provide a standard of living that is close to what we have come to expect, I have set out to prove to myself that I can demonstrate the understanding I am gaining through my self study and research of the things that make our lives easier through manageable, proof-of-concept projects that force me to design & fabricate working models of the devices, appliances, and components that make those things work out of, basically, free stuff or from components, tools commonly found in old or used devices, appliances etc.

Long story short, my first project has been to put together a portable 120v air conditioner that is, at most, efficient enough to cool 1 or two rooms.

The big picture components are:
- Entire refrigeration system (Compressor, condenser, evaporator valve, evaporator coil) from a Brita water cooler left out by my neighbor for heavy trash
- Computer tower box/enclosure
- 3 Electric fans ranging from 45-65cfm
- 1 homemade Dyson bladeless-style ("Air Multiplier") fan
- Electronic components from water cooler and pc tower (2 thermistors, 3 potentiometers
- AC-DC adapter from something 120v AC - 12v DC
- Purchased components - 120V relay, terminals etc.

I've laid everything out, "rigged" it together and tested the design for the power and operating controls and everything worked great. Then I started (too hastily) removing the thin reinforcing rods soldered to the front and back of the vertically snaked condenser coil... And yes, when prying one of the rods from its solder joint, I pulled it off and sprung a leak. In hindsight I realized how STUPID it was to do that. My questions are:

Why didn't my finger freeze off when I stopped it with my thumb (I could feel the pressurized gas coming out of the pinhole but it did not feel the slightest bit cold)?

How long will 5 layers of wound duct tape, 2 zip ties on each side of the hole and a hose clamp around the hole hold out as long as I don't run the compressor?

How do I fix the hole and get the system safe enough to run again? Or, a more liability-friendly way to put it for those EPA-regulation-minded individuals out there, could you provide a detailed explanation of how you, or other certified HVAC professional (if you get my drift) would remedy the system and have it back to pre-oops status?

Tech Specs from Stamp on Compressor:

Manufacturer: Matsu****a Refrigeration
Model: SB24C50GAU6
115V AC - Locked rotor (what's special about that?)
1PH R134a (I'm assuming this is the refrigerant and volume/quantity accept there is a big "22" inked stamped on the dome of the compressor, R22?"
Thermally protected

I've have a technical specifications book with all the formulas so I'm mainly interested in understanding the process for fixing the leak. My hunch is I'm most likely going to hear that I have to capture, weld, vacuum and recharge--details please--but I figure it might be such a small system (i.e. low enough pressure on the high side) that a solder or polymer of some kind will be a long term solution.

Thanks,

Tim

Gary
08-09-2011, 09:02 PM
Why didn't my finger freeze off when I stopped it with my thumb (I could feel the pressurized gas coming out of the pinhole but it did not feel the slightest bit cold)?

Wet your finger and wave it in the air. What you are feeling is a refrigeration effect. As a liquid evaporates (changes from liquid to vapor) it absorbs heat from it's surroundings. In this case it is absorbing heat from your finger. The refrigeration effect ends when all of the liquid has evaporated.

Refrigerants evaporate at very low temperatures. If you had punctured a part of the system that contained refrigerant in liquid form, it could very well have frozen your finger as the liquid evaporated.

TimH
11-09-2011, 11:21 PM
Wet your finger and wave it in the air. What you are feeling is a refrigeration effect. As a liquid evaporates (changes from liquid to vapor) it absorbs heat from it's surroundings. In this case it is absorbing heat from your finger. The refrigeration effect ends when all of the liquid has evaporated.

Refrigerants evaporate at very low temperatures. If you had punctured a part of the system that contained refrigerant in liquid form, it could very well have frozen your finger as the liquid evaporated.



The pinhole is at the very top of the condenser coil as it starts to snake down to the evaporator valve. Are you saying that because the leak was sprung in the part of the system where there is pressurized refrigerant gas and not pressurized liquid refrigerant that my finger didn't freeze off. I understand evaporation temps of refrigerants but my understanding is that once the gas leaves the compressor it will still demonstrate properties of heat absorption regardless of whether it has cooled into a pressurized liquid yet. Could it be that since the system had been off for sometime that all of the pressurized gas stuck in the upper parts of the condenser coil had a chance to cool and pool towards the bottom and the leak did was not exposed enough to suck that liquid out through the pinhole?

I'll be posting pictures so anyone interested can get a better understanding of the setup.

Thanks for your reply!

TimH
13-09-2011, 05:25 AM
- Entire refrigeration system (Compressor, condenser, evaporator valve, evaporator coil) from a Brita water cooler left out by my neighbor for heavy trash

I'll assume that anyone responding to my thread has at least a 608 type 1 certification. The appliance I'm working with is a type I appliance. 608 regulated that these appliance must have service fittings for evacuation and charging to be installed by the compressor manufacturer. This is also a low pressure system and this Brita system is a residential, consumer water cooling and filtration product.*

Pinhole leak or not, 608 regulations recommend evacuation through these required service fittings using solderless piercing valves (with inline filter to capture debris harmful to the compressor) & depending on whether I use the compressor or a stand alone vacuum unit to do the evacuation, the refrigerant can even be stored in a non-pressured container (EPA certified of course). The pressure requirements for the evacuation to be regulation are clearly stated in the 608 regulatory code and the manufacturer's spec sheet clearly states the amount and type of refrigerant and oil and charge pressure.

Thank God a willing refrigeration repair shop owner is willing to work with me. To keep the cost as low as possible I'm going to:

• Purchase a solderless self tapping valve/gauge set. Leak test it and attach it to the compressor service fitting.
• Take the unit to the shop and have him evacuate the system into a container that I cannot legally purchase on my own.
• Take the unit back home, braze the pinhole
• take the unit back to the shop and have him charge the system with the refrigerant I can't purchase on my own
• take the unit back home again and crimp, remove valve, and re-cap the service fitting.

Does that sound about right in terms of process/equipment?

As for phosgene (Install Monkey), is that some kind of scare tactic? Phosgene would be mixed into the refrigerant or oil anyway, but the system is less than 5 years old and had no prior leaks or signs of system contamination that would cause the refrigerant to break down like that.*

Before signing up with this forum I ran into vague, mysterious, Masonic-like comments, posts and yahoo question answers about "you don't understand the system components and how they need to be handled." Really?!?! It's extremely straightforward in the EPA code, you buy certified equipment, follow the 608 evacuation and recharging recommendations/regulations and take the reclaimed refrigerant to a certified reclaimer. What's so technical about that? This isn't a massive HVAC system or a commercial chiller. I'm wondering how many certified technicians actually work on small appliances like these or are really familiar with the requirements for this system type. I just don't understand the trend to cloud the information in mystery. The compounds in these systems follow the same universal laws of fluid dynamics just as water and oil do. Some just perform better/differently for particular situations.

Gary
13-09-2011, 06:22 AM
I'm thinking you are the one with the conspiracy theories.

Grizzly
13-09-2011, 06:56 AM
Tim.
You protest at being treated like a beginner, Yet your questions read like you are?
How do you expect the majority to respond?
This forum is set-up for those of us in the trade to help each other.
And yes we do help those that are untrained when asked in the correct manner.

However do not expect a positive response when you question peoples free advise or indeed their training.
If anyone posts rubbish their own reputation is tarnished as we all vet each other.

Grizzly

chillerman2006
13-09-2011, 09:47 AM
-
I'll assume that anyone responding to my thread has at least a 608 type 1 certification.
Thank God a willing refrigeration repair shop owner is willing to work with me. To keep the cost as low as possible I'm going to:

• Purchase a solderless self tapping valve/gauge set. Leak test it and attach it to the compressor service fitting.
• Take the unit to the shop and have him evacuate the system into a container that I cannot legally purchase on my own.
• Take the unit back home, braze the pinhole
• take the unit back to the shop and have him charge the system with the refrigerant I can't purchase on my own
• take the unit back home again and crimp, remove valve, and re-cap the service fitting.

Does that sound about right in terms of process/equipment?



I have no 608 type 1 cert. & certainly dont need one

If it makes you feel like you know something else, you can presume I know jack diddly like you

But I will tell you if someone tried to tell me to carry out the procedure you describe, I would be even more un-polite than I have been all ready, but that is nothing compared with your bare faced cheek

Get your refrigerant recovered

Braze in a schreider stab and leave it there, preferably braze in 2 one high one low side

if there is refrigerant left in the system get it recovered, if not change the compressor oil prior repairing & recharging

Or just listen to them in the shop & when you have another problem, you can go through all their procedure of puncture tubework, repair, take home crimp & remove valve

I can guess you was as lippy with them at the shop.... did someone really tell you to do this ???

Or are you just making it up as you go ???

Hilarious :D:D

You've made my day, Thankyou.....Its actually been a pleasure laughing at your ignorance & stupidity :D:D

chillerman2006
13-09-2011, 10:03 AM
If anyone posts rubbish their own reputation is tarnished as we all vet each other.

Grizzly

Now the cats out the bag & I know why your all laughing at me ! :eek:

R's chillerman

paul_h
13-09-2011, 02:07 PM
Tim, what do you do for a living?
From what I have read, you want to learn skills in construction and repair? IE, learn a trade or two?

Why don't you do that then and get a job doing that and actually learn things the correct way?
Hobbiest level working isn't going to be that useful, experience is what matters.
Best thing about HVAC is you learn mechanical, fabricating and electrical skills.
Then all you have to learn is farming and drive an old beater car you need to repair a lot, and then you're set.

If you're really worried about peak oil and and bad things in the future, repairing a fridge is pretty low down on the scale.
What use is the fridge if there's no electricity? What use is it when there's no food to put inside? What use is being able to repair one if you (anyone) can't get refrigerant or parts?
You're going to have to delve deeper and really get a full time job in skills you want to learn.

chillerman2006
13-09-2011, 02:16 PM
You Gents

are so polite...I have to read your posts a few times to realize how slow I am sometimes

R's www.chillerman.com (http://www.refrigeration-engineer.com/)

paul_h
13-09-2011, 02:23 PM
You edited post #9 because it was way too mean?
And that was the nicer version?

I've already had my mean post today (on another forum) so didn't feel the need here :)

chillerman2006
13-09-2011, 03:11 PM
Oh ! Yes that was polite mate,

'Install' is away working in London for a couple of days So that was a gentle dual response ;) He will recieve 'Install's when he can get online this evening as just spoke to him and he's stuck on a roof

R's Chillerman (http://www.refrigeration-engineer.com/)






You edited post #9 because it was way too mean?
And that was the nicer version?

I've already had my mean post today (on another forum) so didn't feel the need here :)

install monkey
13-09-2011, 05:18 PM
the phosgene wasnt a scare tactic,u wond find it im the oil,only when a naked flame is exposed to refrigerant,as for your wisdom,why take ur fridge to the repairman to have it decanted,theres f ***all in it,fix the leak pressure test it,get ur fridgie to vac and gas it and see if it works,change the drier and prove the capillary isnt blocked,but u know all this anyway!oh by the way ur asking us if were qualified enough to answer the post!!! Are u qualified enough to take on the advice?? Also is ur fridgie??
- Entire refrigeration system (Compressor, condenser, evaporator valve, evaporator coil) from a Brita water cooler left out by my neighbor for heavy trash

I'll assume that anyone responding to my thread has at least a 608 type 1 certification. The appliance I'm working with is a type I appliance. 608 regulated that these appliance must have service fittings for evacuation and charging to be installed by the compressor manufacturer. This is also a low pressure system and this Brita system is a residential, consumer water cooling and filtration product.*

Pinhole leak or not, 608 regulations recommend evacuation through these required service fittings using solderless piercing valves (with inline filter to capture debris harmful to the compressor) & depending on whether I use the compressor or a stand alone vacuum unit to do the evacuation, the refrigerant can even be stored in a non-pressured container (EPA certified of course). The pressure requirements for the evacuation to be regulation are clearly stated in the 608 regulatory code and the manufacturer's spec sheet clearly states the amount and type of refrigerant and oil and charge pressure.

Thank God a willing refrigeration repair shop owner is willing to work with me. To keep the cost as low as possible I'm going to:

• Purchase a solderless self tapping valve/gauge set. Leak test it and attach it to the compressor service fitting.
• Take the unit to the shop and have him evacuate the system into a container that I cannot legally purchase on my own.
• Take the unit back home, braze the pinhole
• take the unit back to the shop and have him charge the system with the refrigerant I can't purchase on my own
• take the unit back home again and crimp, remove valve, and re-cap the service fitting.

Does that sound about right in terms of process/equipment?

As for phosgene (Install Monkey), is that some kind of scare tactic? Phosgene would be mixed into the refrigerant or oil anyway, but the system is less than 5 years old and had no prior leaks or signs of system contamination that would cause the refrigerant to break down like that.*

Before signing up with this forum I ran into vague, mysterious, Masonic-like comments, posts and yahoo question answers about "you don't understand the system components and how they need to be handled." Really?!?! It's extremely straightforward in the EPA code, you buy certified equipment, follow the 608 evacuation and recharging recommendations/regulations and take the reclaimed refrigerant to a certified reclaimer. What's so technical about that? This isn't a massive HVAC system or a commercial chiller. I'm wondering how many certified technicians actually work on small appliances like these or are really familiar with the requirements for this system type. I just don't understand the trend to cloud the information in mystery. The compounds in these systems follow the same universal laws of fluid dynamics just as water and oil do. Some just perform better/differently for particular situations.