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25-08-2011, 07:01 PM #1
Natural refrigerants - heat-pump friendly?
If you were told that a natural refrigerant had to be used in your next generation of heat-pumps, which one would you choose, & why?
Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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25-08-2011, 08:14 PM #2
Re: Natural refrigerants - heat-pump friendly?
my guess would be co2.as like with r410 it operates at higher pressures than previous systems therefore the units will be more compact.and maybe it will have a widget fitted too,
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25-08-2011, 11:20 PM #3
Re: Natural refrigerants - heat-pump friendly?
The widget concept was actually born when looking into CO2 heat pumps, (in the transion between trans-critical and sub-critical), when working out the calcs, did it move to more regular refrigerants.
As for the heat pump, do you want to remain sub-critical, and not looking at low evap temps, then go for one of the lower pressure HC, I know it as Care 10, (propane I think R600, but I could be wrong, just check, for a refrigerant with normal boiling of -10C at atmospheric)
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25-08-2011, 11:27 PM #4
Re: Natural refrigerants - heat-pump friendly?
using r600 in heatpumps might sort out the cowboy installers! they wont last long when they leave a leak on the system and womph no face!!!
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26-08-2011, 01:12 AM #5
Re: Natural refrigerants - heat-pump friendly?
Ah Co2? I don't Know much about this gas but wouldn't it use more power to run it than a/c on R600? Besides, Co2 is not drawn from the atmosphere and pumped into systems but made in some factory, adding to so called "global warming" Electricity grids are maxed out now. Correct me if i'm wrong.. Mike. (From Aus not Mike from smoggy Toronto.LoL )
To the optimist, the glass is half full. To the pessimist, the glass is half empty.
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26-08-2011, 02:33 AM #6
Re: Natural refrigerants - heat-pump friendly?
Hi Des A.
for me NH3/R717. still the most efficient refrigerant, zero ozone, zero global warming. A system only needs grams not kilos. All we need is a can manufacturer to develop a winding with aluminium coils. Don't think this would be good as a split system but great as a hot water heater.
magoo
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26-08-2011, 11:41 AM #7
Re: Natural refrigerants - heat-pump friendly?
Is there no smog in NTH QLD? I wondered why i was coughing so much
I have been wondering this as well. Does no one make an appropriate small compressor for NH3? If not NH3, propane sounds good but then, depending on where you live, it will bring in another authority which previously had no say in refrigeration. I don't know about you guys but as soon as a combustable gas is introduced we have the gas authorities to deal with and they are a pain in the butt.
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26-08-2011, 12:58 PM #8
Re: Natural refrigerants - heat-pump friendly?
Hi, all
For me definitely ammonia .... agree with Magoo
http://www.mayekawa.com/about/history/
1998
- Developed “VR series” i.e. screw compressor for natural gas.
- Developed ammonia hermetic motor for a small sized screw compressor.
One day in the future when we change our "imagination" about what's making us rich ... changes would began ...
Best regards, Josip
It's impossible to make anything foolproof because fools are so ingenious...
Don't ever underestimate the power of stupid people when they are in large groups.
Please, don't teach me how to be stupid....
No job is as important as to jeopardize the safety of you or those that you work with.
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26-08-2011, 01:19 PM #9
Re: Natural refrigerants - heat-pump friendly?
NH3/R717 or Co2 (transcritical), .. the problem with CO2 is you need a high pressure compressor (150bar), it is possible for small capacity but for bigger capacity there still remain some problems to be fixed.
Also from safety issue I think Nh3 is the better solution.
ammonia21.com is a good site with a lot of info.
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26-08-2011, 01:30 PM #10
Re: Natural refrigerants - heat-pump friendly?
If your dreaming then depending upon the heat source then the best natural refrigerant is water. (type of cascade on say an existing large industrial plant)
Multistage axial compressor, (if they can get one to work)
In the short term i would expext to ammonia or the likes to be in smallish type heat pumps, co2 is here.
Large CO2 not a problem technically right now, but the cost would be sky high (industrial gas compressors)
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29-08-2011, 04:34 PM #11
Re: Natural refrigerants - heat-pump friendly?
Thank IM.
So CO2 : compactness.
Add, high water discharge temps possible.Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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29-08-2011, 04:42 PM #12
Re: Natural refrigerants - heat-pump friendly?
CARE 10 (R600a)
CARE 10 (R600a or isobutane) is a high-purity, single ingredient refrigerant mainly used in domestic fridges and freezers.
Features and benefits
operates at significantly lower pressures than R12 or R134A
lower volumetric refrigerating effect than R12 or R134A
requires a specific R600a compressor
not for use as a retrofit refrigerant
compatible with most common refrigeration materials and lubricantsPhysical Property of r600a:
Critical Temperature, °C 134.71
Critical Pressure, MPa 3.64
Specific Heat of Liquid, 25°C, [KJ/(kg•°C)] 2.38
ODP 0
GWP 11
What are the downsides (except Xplosions)?Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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29-08-2011, 04:43 PM #13
Re: Natural refrigerants - heat-pump friendly?
R600a.
Flammability. What are the acceptable limits, for the 'average Joe' installer, system maintainer, designer?Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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29-08-2011, 04:45 PM #14
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29-08-2011, 04:46 PM #15
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29-08-2011, 04:47 PM #16
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29-08-2011, 04:51 PM #17
Re: Natural refrigerants - heat-pump friendly?
Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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29-08-2011, 05:49 PM #18
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29-08-2011, 05:58 PM #19
Re: Natural refrigerants - heat-pump friendly?
Hi DesA
From what I recall from hydrocarbons course under 500 grams indoors is ok as most it will do if ignited is take your hair off, above this starts to get dangerous, explosive mix is 2-10% with air, so easily ignited indoors, I will scan the course book & email it to you this evening
R's chillermanLast edited by chillerman2006; 29-08-2011 at 06:14 PM.
If the World did not Suck, We would all fall off !
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29-08-2011, 06:21 PM #20
Re: Natural refrigerants - heat-pump friendly?
Hi DesA
sent
having just checked the book it assumes your competant to handle HFC's,
I hope you know a bit about handling mate
R's chillermanIf the World did not Suck, We would all fall off !
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29-08-2011, 07:39 PM #21
Re: Natural refrigerants - heat-pump friendly?
Much obliged Chillerman. Lots to read on the safe handling of these flammable gases.
Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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29-08-2011, 07:52 PM #22
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01-09-2011, 11:56 AM #23
Re: Natural refrigerants - heat-pump friendly?
Guys, what is the smallest comp of any type that will run NH3? If one were to even try to start to make it suitable for resi installs then there better be a ready supply of "X" comp. If they are all too big, what would it take to reduce their capacity (from a manufacturing point of view)?
Same holds true for propane. I know nothing about a comp that works on R600.
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01-09-2011, 12:08 PM #24
Re: Natural refrigerants - heat-pump friendly?
If the World did not Suck, We would all fall off !
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03-09-2011, 01:35 AM #25
Re: Natural refrigerants - heat-pump friendly?
Hi MikeHolm,
it is the corrossive nature of ammonia. Ammonia eats copper and brass. Aluminium is OK, obviously the motor winding insulatin factor is the problem as well, ali coils in motor windings would be larger and a synthetic sleave type insulation is required as well so windings in motor would be extra large in a can or semi-hermetic. Years ago a manufacturer came out with a removable winding on a commercial compressor, the rotor was in a sleave, similar to a Hermetique ammonia pump, don't know what happened to them.
As for compressors I have used auto air compressors in the past as ammonia vapour transfer pumps as they are all alumimium, open drive though. [ from memory the HGC1000,]
With R600 propane I don't know, I have enough trouble with the BBQ when it doesn'T start.
magoo
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03-09-2011, 02:02 AM #26
Re: Natural refrigerants - heat-pump friendly?
Never use a spark igniter on the BBQ as they always break so always a butane lighter. Also check for spiders in the tubes, happens all the time.......but I digress.....If you come across any of the old compressor info let us know. I think it is time someone rocked the boat (or at least looked at the possibilities)
I guess king valves etc, would have to be stainless and are there reversing valves in steel or SS? RESI sized???
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03-09-2011, 07:00 PM #27
Re: Natural refrigerants - heat-pump friendly?
only pots ive seen on r290,600 are standard domestic,danfoss sc15's and lunite aj type.
as long as it has a ptc relay and a lil flammable sticker hey presto! compressor changes are fun,just tape up ur eyebrows-wooomph! haha
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03-09-2011, 07:40 PM #28
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Re: Natural refrigerants - heat-pump friendly?
For R600a LEL (lower explosive limit) is 38g/m^3 or 1,8% koncentraction (safety factor 4).
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04-09-2011, 04:23 PM #29
Re: Natural refrigerants - heat-pump friendly?
Are spark-proof tools required?
Engineering Specialist - Cuprobraze, Nocolok, CD Technology
Rarefied Technologies ( SE Asia )
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04-09-2011, 04:27 PM #30
Re: Natural refrigerants - heat-pump friendly?
they do do reclaim rigs and vac pumps that are spark proof-but ive done pot changes on freezers with a bog standard vac pump. just keep the area well ventilated and use plenty of nitrogen
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04-09-2011, 05:02 PM #31
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04-09-2011, 05:07 PM #32
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04-09-2011, 05:15 PM #33
Re: Natural refrigerants - heat-pump friendly?
R600a? Electrolux and some sharp domestic refrigerators are using that now, gets them a higher efficiency rating over R134a.
R290? People are putting that into their car a/cs or R22 split systems themselves over here. Hychill is a local crowd selling HC rerigerants, I don't know if it's straight R290 or some HC blend though.
edit: http://www.hychill.com.au/products/
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04-09-2011, 06:00 PM #34
Re: Natural refrigerants - heat-pump friendly?
Excuse my ignorance but can you just use BBQ propane? Why buy it from a refrigerant supplier?
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04-09-2011, 06:03 PM #35
Re: Natural refrigerants - heat-pump friendly?
Material Safety Data Sheet
R290 PROPANE
- CHEMICAL PRODUCT AND COMPANY IDENTIFICATION
PRODUCT NAME:
PROPANE
DISTRIBUTOR:
National Refrigerants, Inc.
661 Kenyon Avenue
Bridgeton, New Jersey 08302
FOR MORE INFORMATION CALL: IN CASE OF EMERGENCY CALL:
(Monday-Friday, 8:00am-5:00pm) CHEMTREC: 1-800-424-9300
1-800-262-0012
- COMPOSITION / INFORMATION ON INGREDIENTS
INGREDIENT NAME CAS NUMBER WEIGHT %
Propane 74-98-6 100
- HAZARDS IDENTIFICATION
EMERGENCY OVERVIEW: WARNING! Flammable gas. Contents under pressure. Causes damage to the following organs: Nervous System. Vapor may cause flash fire. Keep away from heat, sparks and flame. Do not puncture or incinerate container. Keep container closed. Use only with adequate ventilation. Contact with rapidly expanding gases can cause frostbite.
POTENTIAL ACUTE HEALTH EFFECTS:
SKIN:
No known significant effects or critical hazards.
EYES:
No known significant effects or critical hazards.
INHALATION:
Acts as simple asphyxiant.
INGESTION:
Ingestion is not a normal route of exposure for gases.
POTENTIAL CHRONIC HEALTH EFFECTS:
CARCINOGENIC EFFECTS:
Not available.
MUTAGENIC EFFECTS:
Not available.
TERATOGENIC EFFECTS:
Not available.
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 1 of 6 Current Issue Date: December, 2008
PROPANE
MEDICAL CONDITIONS AGGRAVATED BY OVEREXPOSURE:
Acute or chronic respiratory conditions may be aggravated by overexposure to this gas.
See Toxicological Information (section 11)
- FIRST AID MEASURES
No action shall be taken involving any personal risk or without suitable training. If fumes are still suspected to be present, the rescuer should wear an appropriate mask or a self-contained breathing apparatus. It may be dangerous to the person providing aid to give mouth-to-mouth resuscitation.
SKIN:
In case of contact, immediately flush skin with plenty of water. Remove contaminated clothing and shoes. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get medical attention.
EYES:
Immediately flush eyes with plenty of warm water for at least 15 minutes. Get medical attention.
INHALATION:
Immediately remove to fresh air. If breathing has stopped, give artificial respiration. If breathing is difficult, qualified personnel may give oxygen. Get medical attention immediately.
INGESTION:
Do NOT induce vomiting unless directed to do so by medical personnel. Never give anything by mouth to an unconscious person. Get medical attention if symptoms appear.
FROSTBITE:
Try to warm up the frozen tissues and seek medical attention.
- FIRE FIGHTING MEASURES
FLAMMABLE PROPERTIES
Flammability of product:
FLAMMABLE
Autoignition temperature:
841.7°F (449.85°C)
Upper flame limit (volume % in air):
9.5%
Lower flame limit (volume % in air):
2.1%
Products of combustion:
These products are carbon oxides (CO,CO2).
Fire hazards in presence of various substances:
Extremely flammable in presence of open flames, sparks and static discharge of oxidizing materials.
Fire fighting media and instructions:
CO2, dry chemicals, water spray, or fog.
If involved in fire, shut off flow immediately if it can be done without risk. Apply water from a safe distance to cool container and protect surrounding area.
Extremely flammable. Gas may accumulate in confined areas, travel considerable distance to source of ignition and flash back causing fire or explosion.
Special protective equipment for fire-fighters:
Fire fighters should wear appropriate protective equipment and self- contained breathing apparatus (SCBA) with a full facepiece operated in positive pressure mode.
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 2 of 6 Current Issue Date: December, 2008
PROPANE
- ACCIDENTAL RELEASE MEASURES
PERSONAL PRECAUTIONS:
Immediately contact emergency personnel. Keep unnecessary personnel away. Use suitable protective equipment (Section 8). Shut off gas supply if this can be done safely. Isolate area until gas has dispersed.
ENVIRONMENTAL PRECAUTIONS:
Avoid dispersal of spilled material and runoff and contact with soil, waterways, drains and sewers.
- HANDLING AND STORAGE
NORMAL HANDLING:
Keep container closed. Use only with adequate ventilation. Keep away from heat, sparks and flame. To avoid fire, minimize ignition sources. Use explosion-proof electrical (ventilating, lighting and material handling) equipment. Do not puncture or incinerate container. High pressure gas. Use equipment rated for cylinder pressure. Close valve after each use and when empty. Protect cylinders from physical damage; do not drag, roll, slide, or drop. Use a suitable hand truck for cylinder movement.
STORAGE RECOMMENDATIONS:
Keep container tightly closed. Keep container in a cool, well-ventilated area. Cylinders should be stored upright, with valve protection cap in place, and firmly secured to prevent falling or being knocked over. Cylinder temperatures should not exceed 52°C (125°F).
- EXPOSURE CONTROLS / PERSONAL PROTECTION
ENGINEERING CONTROLS:
Use only with adequate ventilation. Use process enclosures, local exhaust ventilation, or other engineering controls to keep airborne levels below recommended exposure limits. The engineering controls also need to keep gas, vapor or dust concentrations below any explosive limits. Use explosion-proof ventilation equipment
PERSONAL PROTECTION:
SKIN:
Personal protective equipment for the body should be selected based on the task being performed and the risks involved and should be approved by a specialist before handling this product.
EYE:
Safety eyewear complying with an approved standard should be used when a risk assessment indicates this is necessary to avoid exposure to liquid splashes, mists or dusts.
RESPIRATORY:
Use a properly fitted, air-purifying or air-fed respirator complying with an approved standard if a risk assessment indicates this is necessary. Respirator selection must be based on known or anticipated exposure levels, the hazards of the product and the safe working limits of the selected respirator.
The applicable standards are (US) 29 CFR 1910.134 and (Canada) Z94.4-93
HANDS:
Chemical-resistant, impervious gloves or gauntlets complying with an approved standard should be worn at all times when handling chemical products if a risk assessment indicates this is necessary.
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 3 of 6 Current Issue Date: December, 2008
PROPANE
Personal protection in case of a large spill:
A self-contained breathing apparatus should be used to avoid inhalation of the product.
Consult local authorities for acceptable exposure limits.
- PHYSICAL AND CHEMICAL PROPERTIES
MOLECULAR WEIGHT:
44.11 g/mole
MOLECULAR FORMULA:
C3H8
BOILING/CONDENSATION POINT :
-43.2°F (-41.79°C)
MELTING/FREEZING POINT:
-302.6°F (-185.89°C)
CRITICAL TEMPERATURE:
205.9°F (96.6°C)
VAPOR PRESSURE
: 109 psig
VAPOR DENSITY:
1.6 (Air=1)
SPECIFIC VOLUME (ft
3/lb):
8.62069
GAS DENSITY(lb/ft
3):
0.116
PHYSICAL CHEMICAL COMMENTS:
Not available
- STABILITY AND REACTIVITY
STABILITY and REACTIVITY:
The product is stable.
INCOMPATIBILITIES with various substances:
Extremely reactive or incompatible with oxidizing agents.
- TOXICOLOGICAL INFORMATION
TOXICITY DATA:
IDLH:
2100 ppm
Chronic effects on humans:
Causes damage to the following organs: the nervous system.
Other toxic effects on humans:
No specific information is available in our database regarding the other toxic effects of this material for humans.
SPECIFIC EFFECTS:
Carcinogenic effects:
No known significant effects or critical hazards.
Mutagenic effects:
No known significant effects or critical hazards.
Reproductive toxicity:
No known significant effects or critical hazards.
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 4 of 6 Current Issue Date: December, 2008
PROPANE
- ECOLOGICAL INFORMATION
Products of degradation:
These products are carbon oxides (CO,CO2) and water.
Toxicity of the products of biodegradation:
The product itself and its products of degradation are not toxic.
Environmental fate:
Not available
Environmental hazards:
No known significant effects or critical hazards.
Toxicity to the environment:
Not available.
- DISPOSAL CONSIDERATIONS
Product removed from the cylinder must be disposed of in accordance with appropriate Federal, State, and local regulations. Return cylinders with residual product to Airgas, Inc. Do not dispose of locally.
- TRANSPORT INFORMATION
DOT PROPER SHIPPING NAME:
Propane, see also Petroleum Gases, Liquefied
SHIPPING LABEL(s):
FLAMMABLE GAS
PACKING GROUP:
Not applicable (gas)
HAZARD CLASS:
2.1
UN NUMBER:
UN 1978
- REGULATORY INFORMATION
U.S. FEDERAL REGULATIONS:
TSCA 8(b) inventory: Propane
SARA 302/304/311/312 extremely hazardous substances: No products were found.
SARA 302/304 emergency planning and notification: No products were found.
SARA 302/304/311/312 hazardous chemicals: Propane
SARA 311/312 MSDS distribution – chemical inventory – hazard identification: Propane: Fire hazard, Sudden Release of Pressure
Clean Water Act (CWA) 307: No products were found.
Clean Water Act (CWA) 311: No products were found.
Clean Air Act (CAA) 112 accidental release prevention: Propane
Clean Air Act (CAA) 112 regulated flammable substances: Propane
Clean Air Act (CAA) 112 regulated toxic substances: No products were found.
STATE REGULATIONS:
Pennsylvania RTK: Propane: (generic environmental hazard)
Massachusetts RTK: Propane
New Jersey: Propane
CANADA
WHMIS (Canada):
Class A: Compressed gas
Class B-1: Flammable gas
CEPA DSL: Propane
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 5 of 6 Current Issue Date: December, 2008
PROPANE
- OTHER INFORMATION
UNITED STATES
LABEL REQUIREMENTS:
Flammable Gas
Contents under pressure
Causes damage to the following organs: Nervous System.
Vapor may cause flash fire
CANADA
LABEL REQUIREMENTS:
Class A: Compressed Gas
Class B-1: Flammable gas
HAZARD RATING SYSTEMS:
NFPA RATINGS: HMIS RATINGS:
HEALTH =1 HEALTH =1
FLAMMABILITY =4 FIRE HAZARD =4
INSTABILITY =0 REACTIVITY =0
SPECIAL =None PERSONAL PROTECTION =C
National Refrigerants, Inc. believes that the information and recommendations contained herein (including data and statements are accurate as of the date hereof). NO WARRANTY OF FITNESS OR ANY PARTICULAR PURPOSE, WARRANTY OF MERCHANT ABILITY, OR ANY OTHER WARRANTY, EXPRESSED OR IMPLIED, IS MADE CONCERNING THE INFORMATION PROVIDED HEREIN. The information provided herein relates only to the specific product designated and may not be valid where such product is used in combination with any other methods of use of the product and of the information referred to herein are beyond the control of National Refrigerants. National Refrigerants expressly disclaims any and all liability as to any results obtained or arising from any use of the product or reliance on such information.
____________________________________________________________________________________________________ ________
MSDS: PROPANE Page 6 of 6 Current Issue Date: December, 2008
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04-09-2011, 06:24 PM #36
Re: Natural refrigerants - heat-pump friendly?
Last edited by paul_h; 04-09-2011 at 06:27 PM.
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04-09-2011, 06:26 PM #37
Re: Natural refrigerants - heat-pump friendly?
Hey Install...have you got the full up to date version in larger print...having trouble reading that one
If the World did not Suck, We would all fall off !
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04-09-2011, 06:31 PM #38
Re: Natural refrigerants - heat-pump friendly?
thought u might of gone blind from watching dogwanks haha-i only copied and pasted it-the data sheet haha
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04-09-2011, 06:45 PM #39
Re: Natural refrigerants - heat-pump friendly?
Looking at the MSDS sheet, it would seem that there are no additives. I can see the moisture issue as it could be as high as 12% from my 20 year old fuels courses (it is for natural gas although this is a product of combustion and that includes the humidity in the combustion air).
I would look at it more closely. This might be a question for Refrigeration 101 but why is Ammonia more efficient than r410 for example (other than the pressure issue) and is r290 also more efficient? If one were to create an industry change to either of these, there must be more benefit than just lower pressures.
Again, I let my ignorance show.
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11-09-2011, 03:56 AM #40
Re: Natural refrigerants - heat-pump friendly?
Thanks install, I've got some ideas in your post. I'm just a learner so excuse me guys. thanks.
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11-09-2011, 06:16 AM #41
Re: Natural refrigerants - heat-pump friendly?
Mike, From what i have read, hydrocarbons for refrigeration are specific quantities of isobutane/ propane/ n-butane, minus the water factor in BBQ gas, that has everything in it including the kitchen sink. (So to speak.. might just be an Aus saying .) BBQ gas is in liquid form at 188 PSI, give or take, depending on where you live, so my gas supplier tells me. So many imported domestic and light commercial equipment with R600a and R290 here now, yet i've not had the opportunity to work on them yet..Mike.
To the optimist, the glass is half full. To the pessimist, the glass is half empty.
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11-09-2011, 12:28 PM #42
Re: Natural refrigerants - heat-pump friendly?
Hi Mike
Ammonia's specific hit transfer is far better than R410a & all hydrocarbons are far lighter than fluoro based refrigerants roughly half the weight & as they are measured in kj per kg they have twice the mass to carry out the work, hope that helps mate
R's chillermanIf the World did not Suck, We would all fall off !
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11-09-2011, 02:46 PM #43
Re: Natural refrigerants - heat-pump friendly?
Mike
Here is some more info
Note R600 half cooling capacity of R134a
Also shows charging/decanting/brazing procedures
R's chillermanLast edited by chillerman2006; 11-09-2011 at 03:00 PM. Reason: added comparetor
If the World did not Suck, We would all fall off !
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11-09-2011, 04:15 PM #44
Re: Natural refrigerants - heat-pump friendly?
This will take some time to digest.....keep it coming
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11-09-2011, 04:51 PM #45
Re: Natural refrigerants - heat-pump friendly?
Hi MIke
am on limits of my understanding here so please wait for confirmation from another before taking all as 100% correct ( DesA / Peter_1 HELP !!! before I drown )
Right well if we go back to Ammonia v's R410a first
Ammonia has a high 'specific heat capacity'
R410a has a lower 'specific heat capacity'
specific heat capacity (cp) is measured as 'joule per gram' and the higher the number the more work that fluid can do or the more heat that fluid is able to absorb
Water for instance has a high 'cp' (4.186) but the more glycol that is mixed with water the lower the 'cp' becomes & the less heat that fluid can now absorb
The less work a fuid can do (less heat it can absorb) the more the system has to run to acheive the same results
R's chillerman
added .... its ok Mike ... confirmed by Peter_1Last edited by chillerman2006; 11-09-2011 at 09:47 PM. Reason: Peter_1 Thanks
If the World did not Suck, We would all fall off !
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11-09-2011, 05:37 PM #46
Re: Natural refrigerants - heat-pump friendly?
Frigopol of Austria is it MAgoo, a mix between a hermetic and an open compressor. I have some in my shop, vertical compressors.
But Bock did the +/- same on their AM range but they still needed a shaft seal.
They are still fabricated these days. www.frigopol.com
You can use a small open compressor like a Dorin for NH3. But you then loose a part of the absorbed power. But NH3 gives a very high discharge temperature, especially when you superheat it the suction in a controlled way a little bit further then normal.
@Chillerman, I think you explained the term specific heat very well in your las post...the heat absorbing ability of a refrigerant I should call it.It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.
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11-09-2011, 05:44 PM #47
Re: Natural refrigerants - heat-pump friendly?
I thought 150 gr was the max for R290.
They're researching a lot on R290 for the moment. A paper was presented very recent by DTI (the same university of Coolpack)
Had last a domestic freezer to repair for a friend and he told me that he had a leak around the door heater (discharge pipe around the door) He asked me to bypass the door heater so that I could recharge it with R134a.
Never looked to the nameplate - very stupid of me - and took my brazing torch to solder a schradervalve in the suction port of the hermetic. Process tube came loose from the compressor and you can guess..the R290 (no r134a) was still on it.
We didn't needed to repair it afterwards, it burned as a constant flame of 15 cm to 20 cm high, full power for at least 1 minute. The back of the freezer was complete melted. Lucky, I was in my open shop.
So 150 gr is dangerous, I saw and felt it like and smelled like a roasted chicken.It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.
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11-09-2011, 06:04 PM #48
Re: Natural refrigerants - heat-pump friendly?
Hi Peter
some limits shown on attached
R's chillermanIf the World did not Suck, We would all fall off !
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11-09-2011, 06:14 PM #49
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11-09-2011, 06:37 PM #50
Re: Natural refrigerants - heat-pump friendly?
Paul_H, you're of course right but why recover if the unit is already 'empty' and you hardly have time to do such a s..t job like repairing a domestic fridge? But it was for a friend and between 2 jobs in a hurry.
Mmm, I think it's not allowed to recover R290 with a standard recovery unit
The fridge is still here, should make some pictures of the back of it.
We work regular on ethylene and propylene systems, so I know how to do it safely.
But only to say that 150 gr is not so little as they say where you will only see a small spark. It burns heavy and long. You can learn from my faults.
BTW Paul, we drive our van's the opposite way (your avatar) I knew it was a mirror view as we drive here but I didn't knew I had to turn my mirror the other direction, upside down.Last edited by Peter_1; 11-09-2011 at 06:40 PM.
It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.