You have a pallet load of compressors, now I want to be your buddy! .... Really am sorry about the previous comment. It is really a cool project, no pun intended, ok I let it slip. I grew up in an auto body shop and I'm sure my manners are proof. Really am proud to see people building usefull things and experimenting. Keep up the good work! As anyone knows a funeral can humble a man. Best regards to you and yours. -P
@Plutoniuts lol yer it may seem like a silly mistake but when you have enough new compressors to use them as door stops, its great fun trying different things, even if they don't work out.
I still have loads of compressors in the boxes today, but nothing to use them on :(. I got sick of making air compressors, although occasionally get a request for one.
nice we project, what about installing a solenoid valve with a delay on start timer that vents to atmosphere for start up for 10 seconds or so as an unloading device, also may have to install a one way valve inline to your air tank , hope you have changed the oil in the compressor to something not hygroscopic as it will go acidic and eat out the windings, . and then there is the no cooling to the compressor the refrigerant would usually provide problem . neat we project keep up the good work
Hello! I've made my airbrush compressor with same exact Danfoss compressor. It's hooked to pressure switch that cuts power off when filled to 7bars. I've noticed this same problem with short cycling. Have you managed to overcome this thermostat starter issue? And what compressor would be ideal to use in this kind of device? Any brands to look for? Many thanks already.
@Aussie50 Similar problem with a compressor I built years ago. I bought a one way check valve in the line out from the compressor (mine screwed into the reservoir and T-ed off of the pressure line prior to the check valve from that I ran copper tubing to a normally open electric(ac) pressure valve and tied it into the the pressure switch. Reservoir reaches full pressure shuts down the compressor and dumps the pressure in the line. On next start up, there is no resistance.
seriously ? you didnt know the duty cycle of the fridge compressor before you started that abortion of a project. what a waste of time and air ....duh
To not wear out quickly, these fridge compressors need a very small flow of oil passing through them at all times when running. You need to have some recirculating oil and absolutely NO condensation or impurities, as the motor runs in the oil bath for cooling, any moisture will short it out to the case and possibly make the compressor live in which case you could easily kill yourself.
@Aussie50 I agree that if used for long enough to heat the oil and drive off the moisture you're fairly safe. It's just that today's episode opened my eyes to what can happen.
@Aussie50 Remember,.. 15mA will stop your heart, permanently, very easily achieved at mains voltages with just the slightest problem in your earth.
That's what killed a teen aged girl drinking out of a tap at Port Pirie High School several years ago, it' s pipe was used as part of the building earth circuit and was in moderately damp earth, when a washing machine in the home science centre shorted out.
Say what you will, it does happen and the consequences
@ozzirt Humans living with technology will always result in the occasional deaths, the idea of living in a world of no fatalities of any kind is a fantasy!
just like road deaths, its inevitable, and wrapping everyone in bubble wrap will not change a thing.
@ozzirt it would be a one in a million chance that somebody fries them-self with one simply because of a bit of atmospheric moisture. a Chinese air compressor set on a humid day is more dangerous.
@Aussie50 Yep,.. you should tell that to the patient we resuscitated today, I'm sure he'll have something to say if he has no long lasting brain damage.
THAT is why I came on here tonight for that exact purpose. He only made the compressor three months ago and had been using it to spray "dope" on, and paint model aircraft.
I've even had Worksafe Victoria threaten to audit my one-man hobby shop. bunch of nazi pricks.
I've been running tandem fridge compressors for the last 2 years as my main shop compressor, on constant cycle (running up to 25 times a week or more) with little more than 2 - 3 oil top ups per yer, no earth breaker trip do far!
Your patient probably ran the compressor until it overheated and burned the varnish off the windings, without earth, any motor will kill
@ozzirt lol, I'm just fed up with goodie goodies running around making work so difficult its easier and cheaper to go over to China and get things made.
I support workplace safety, but common sense safety, like don't stick your head in a lathe kind of safety!, not this over the top bullshit where a drill press needs a full metal guard around the table and spindle, and a light barrier that shuts it down if you even so much as scratch your nose!
would it work if you put a small hole in the outlet line and then just after the hole put a one way valve to hold the tank presser but release the compressor presser?
I have one set up as a compressor works fine just make sure the crank case has oil and use a fan to keep it cool as well as using a checkvalve inline and A oil catcher as from time to time some oil will come from the discharge line. also filter the suction line to keep junk out of the compressor. mine is on at 110 psi and off 130 psi . compressor from an old 1980's frige used r12 originally.
This hermetic compressor relies on superheated refrigerant coming back via suction line to keep the system from over heating. A refrigeration line set is designed to keep the oil flowing back to the compressor, there is a delivery method in side the compressor to suck oil from the bottom of the compressor and lube the the moving parts. you are setting this compressor up to fail, with out an effective cooling method it will go off on internal overload every time. This is not a limitation.
@Goldstarelite I've never had one go off on internal over heat protection, but I guess if you run it hard enough it will. but by that stage it would be best to go out and buy a real workshop air compressor.
oil top-up is a bit sketchy, because there is no sight glass on small comps, but the centrifugal oil pickup is pretty long so it can be over-filled a bit.
and a few tablespoons of oil every few running hours is adequate for a low-hour comp.
I decided against the oil sightglass and fitted an hours run counter to the pressure switch contacts instead. The counter logs the compressors running time and tells you how much oil to add. I emptied the oil out to check the consumption when the counter showed 5 hrs and again at 10hrs..but so far it hasnt used a drop. I`ll test again when the counter shows 20 hours..in about 2 months time :)
You've probably already resolved this but you need a head pressure relief valve that us usually built into some cut off switches. No pump can start with air pressure on it's head so the valve bleeds it off when the regulator stops the compressor.
You can try using a non return vale and a bleed off valve. this will lower the internal pressure in the pump to let it restart at a lower pressure. Tank pressure will still remain high.
use older compressors, i use an old kirby fridge compressor from a 30 year old fridge, they will start with a load or not, just makes the compressor wobble a bit, Only drawback is moisture accumulating in discharge
and what is the max pressure psi we can get from them. and can we power them on for many hours. i think domestic fridge comps can not but scrolls can work hours without stopping as in air conditioners. thanks for your answer and nice videos.
I have had a rotary up to 600psi, but not a domsetic fridge compressor.
I havn't done many tests on scrolls but they can run for a long time in an air conditioner. but the main factor that contributes to their run time is subcooling.
scrolls are very dependent on cold gas returning from the evaporator to cool the electric motor.
If you were to run a scroll continuously with no subcooling it may overheat and die.
@Aussie50 Hey, Its not sub-cooling that cools the compressor. It is superheat. You cannot readily compress a liquid. when refrigerant is sub-cooled it is in a liquid form, the whole reason for a metering device is to meter the refrigerant into the evap so by the time it exits the evap it has at least 10degree superheat, this is a safety for the compressor to ensure it does not suck back liquid. the refrigerant is sub-cooled when it leaves the condenser. You have it backwards.
may i ask that if compressors pumps oil instead of gas, how does not occur problem when they used in cooler units. i mean, they not send oil with the r22 gas? so did a problem in gas cycle? And my second question, if it is possible to ad an oil separator to a scroll compressor, and maybe send oil back to reservoir, possible?
most compressors do send a bit of oil through the system as they run, but that oil needs to return to the compressor in order lubricate the compressor over its lifespan.
my theory is that the pressure difference between the suction and discharge side on the Scroll compressor forces the oil to stay in the compressor head. running one at normal atmospheric pressure would drain the crank case in a matter of hours.
THe oil separator is the best idea IMO. just fit a filter to it too, keep any coagulated oil out of the crank case (moisture from the separator may cause problems)
I would imagine that a reciprocating compressor would also incur loads of vibrations (I presume that was a rotary/scroll type in this vid?) unless it is prohibitively large with a good mounting suspension system and/or possibly a lot of cylinders.
I suppose they are OK for pumping loads of refrigerants though (which is pretty much what I intend to do) rather than air. The reciprocating ones are not too bad for air and I think they use exactly those in many commercial units too.
You reckon I will get a decent one from a new refrigerator? I haven't seen many with scrolls - just recip comp. I would think maybe a "5-star" fridge would have it.
Apparently mattyvt93 has seen some in bar fridges although I've never seen any.
What advantages do recip. comps have over scroll comps?
The correct name is "Klixon".It is a bi-metal switch that breaks both by heat and excessive current.If in doubt, by-pass it and check the current being pulled by the comp. by the plate-load.
Sometimes old refrigeration compressors do leak back through the flappers.I f you fit a standard water non-return valve to the 2 suction pipes, it cancels this problem.
You might enjoy "Doolin's Troubleshooter's Bible". 1964 edition is the one I have. I'm not very handy but he says you can put a capacitor on a 'fridge motor for increased starting torque.
what about condensation which would eventually build up in the discharge chamber of the compressor, that can't be good for it in the long run, or if you are using it all the time
if you put a check valve and release valve at the compressor when it stops it would depressurize the compressor but not the tank so it can start on demand. i think that should work?
i know the compressor and a check valve but if you put a unloader valve in you will nee another check valve. you have put a bigger compressor in so im just talking crap now.lol
I think its actually called a Posistor, the nature of how it works is that it supplies power to the start windings and heats up in the process, increasing in resistance untill there is little or no power going to the start windings.
If you power the compressor down the posistor will remain hot for a while, and thus if I try restarting the compressor whilst it is hot, no power will be delivered to the start windings.
they taught me about these in school but i forgot most of it now :(
why cant you have a relay and 2 of those posistor things and when the compressor stops it changes to the second one for quick start and the next stop it changes to the first one and so on. should be easy to do. :)
if its an older style compressor, fine mineral oil works fine, like Singer machine oil, if its a new one thats designed for R410A etc.. its Polyester Oil, in which case you need to talk to a refrigeration supplier. POE oil is not compatible with mineral.
Ads far as air tool ol goes, I don't see why it would create a problem since we are not dealing with refrigerant compatibility issue.
Other option may be auto trans oil? never tried it but it is made for fine high pressure parts
I guess you could try a small start capacitor and conventional starting relay, but I don't think the start windings are designed for high impulse starting current.
I may try that today with a HST starter on the LST comp
What size is the refrigerator compressor? (dimensions or power rating)
Mytokondrion 1 month ago
Danfoss refrigeration compressor?
Overheats because refrigeration compressors rely on cooling from the refrigerant returning on the suction line.
BagFullOfBalls 1 month ago
You have a pallet load of compressors, now I want to be your buddy! .... Really am sorry about the previous comment. It is really a cool project, no pun intended, ok I let it slip. I grew up in an auto body shop and I'm sure my manners are proof. Really am proud to see people building usefull things and experimenting. Keep up the good work! As anyone knows a funeral can humble a man. Best regards to you and yours. -P
Plutoniuts 2 months ago
@Plutoniuts lol yer it may seem like a silly mistake but when you have enough new compressors to use them as door stops, its great fun trying different things, even if they don't work out.
I still have loads of compressors in the boxes today, but nothing to use them on :(. I got sick of making air compressors, although occasionally get a request for one.
Aussie50 2 months ago
nice we project, what about installing a solenoid valve with a delay on start timer that vents to atmosphere for start up for 10 seconds or so as an unloading device, also may have to install a one way valve inline to your air tank , hope you have changed the oil in the compressor to something not hygroscopic as it will go acidic and eat out the windings, . and then there is the no cooling to the compressor the refrigerant would usually provide problem . neat we project keep up the good work
skags2 2 months ago
Hello! I've made my airbrush compressor with same exact Danfoss compressor. It's hooked to pressure switch that cuts power off when filled to 7bars. I've noticed this same problem with short cycling. Have you managed to overcome this thermostat starter issue? And what compressor would be ideal to use in this kind of device? Any brands to look for? Many thanks already.
Greetings from Finland
darkstari 2 months ago
@darkstari you can use a starting cap and potential relay off a similar compressor, or a hard-start kit.
Aussie50 2 months ago
@Aussie50 Similar problem with a compressor I built years ago. I bought a one way check valve in the line out from the compressor (mine screwed into the reservoir and T-ed off of the pressure line prior to the check valve from that I ran copper tubing to a normally open electric(ac) pressure valve and tied it into the the pressure switch. Reservoir reaches full pressure shuts down the compressor and dumps the pressure in the line. On next start up, there is no resistance.
queenofyeay 2 months ago
seriously ? you didnt know the duty cycle of the fridge compressor before you started that abortion of a project. what a waste of time and air ....duh
Plutoniuts 2 months ago
@Plutoniuts do you honestly think any hobby creation comes together perfectly the first time without a little R&D? get stuffed.
what else do you use pallet loads of surplus compressors for!
Aussie50 2 months ago 2
nice computer case lol
MrTpengineer 3 months ago
not a good idea you will overheat the thermal overload with short cycle start and stops and pressures too high will release the inturnal releaf valve
MrAirdoctor 5 months ago
The idea is great, only a couple of problems.
To not wear out quickly, these fridge compressors need a very small flow of oil passing through them at all times when running. You need to have some recirculating oil and absolutely NO condensation or impurities, as the motor runs in the oil bath for cooling, any moisture will short it out to the case and possibly make the compressor live in which case you could easily kill yourself.
You MUST use an ELCB with this or risk DEATH.
ozzirt 6 months ago
@ozzirt Compressors are consumable, so if it does get impurities in the oil and wear out its no big deal, just fit another.
as for the electrical issue, you have a good point about people pouring oil back in that may have water in it..
under normal operation with clean oil fill, any moisture evaporates from the oil when the compressor warms up (they do run hot when filling a tank)
It would be silly not to earth a compressor or electric motor of any kind, and a ELCB is preferable as you say.
Aussie50 6 months ago
@Aussie50 I agree that if used for long enough to heat the oil and drive off the moisture you're fairly safe. It's just that today's episode opened my eyes to what can happen.
ozzirt 6 months ago
@ozzirt if it zapped him it probably wasn't earthed at all, in which case anything with a motor will kill him if he has no earth and cooks/drowns it.
Darwin at work IMO
Aussie50 6 months ago
@Aussie50 Remember,.. 15mA will stop your heart, permanently, very easily achieved at mains voltages with just the slightest problem in your earth.
That's what killed a teen aged girl drinking out of a tap at Port Pirie High School several years ago, it' s pipe was used as part of the building earth circuit and was in moderately damp earth, when a washing machine in the home science centre shorted out.
Say what you will, it does happen and the consequences
ozzirt 6 months ago
@ozzirt Humans living with technology will always result in the occasional deaths, the idea of living in a world of no fatalities of any kind is a fantasy!
just like road deaths, its inevitable, and wrapping everyone in bubble wrap will not change a thing.
Aussie50 5 months ago
@Aussie50 Yep, that'll make a great epitaph for your headstone.
Some people just have all the answers.
ozzirt 5 months ago
@ozzirt it would be a one in a million chance that somebody fries them-self with one simply because of a bit of atmospheric moisture. a Chinese air compressor set on a humid day is more dangerous.
Aussie50 6 months ago
@Aussie50 Yep,.. you should tell that to the patient we resuscitated today, I'm sure he'll have something to say if he has no long lasting brain damage.
THAT is why I came on here tonight for that exact purpose. He only made the compressor three months ago and had been using it to spray "dope" on, and paint model aircraft.
ozzirt 6 months ago
@ozzirt yeh yeh, enough paranoia.
I've even had Worksafe Victoria threaten to audit my one-man hobby shop. bunch of nazi pricks.
I've been running tandem fridge compressors for the last 2 years as my main shop compressor, on constant cycle (running up to 25 times a week or more) with little more than 2 - 3 oil top ups per yer, no earth breaker trip do far!
Your patient probably ran the compressor until it overheated and burned the varnish off the windings, without earth, any motor will kill
Aussie50 6 months ago
@Aussie50 Ahhh,... now we see it all. You are one of those who's ignorance and stupidity instigated the formation groups like Worksafe.
As the renowned American civil war general said when warned of the possibility of a sniper, "They couldn't hit an elephant at this dist,...."
ozzirt 6 months ago
@ozzirt lol, I'm just fed up with goodie goodies running around making work so difficult its easier and cheaper to go over to China and get things made.
I support workplace safety, but common sense safety, like don't stick your head in a lathe kind of safety!, not this over the top bullshit where a drill press needs a full metal guard around the table and spindle, and a light barrier that shuts it down if you even so much as scratch your nose!
Aussie50 5 months ago
oil seperater
deanoobaby 7 months ago
try filling up a rotary compressor with water and see how well water lubricares it. :)
cheetawolf 7 months ago
This has been flagged as spam show
You need a start
fridgy17 8 months ago
p es oi
187ONaNOOB 10 months ago
would it work if you put a small hole in the outlet line and then just after the hole put a one way valve to hold the tank presser but release the compressor presser?
wcocowcocow 11 months ago
This has been flagged as spam show
ass, ass, ass hot
gachu26 1 year ago
Of the arcus fridges i've seen,the compressors seem pretty good at starting at pressure. Thats two fridges, by the way
airconguy1 1 year ago
you coukd reverse a traxoil mounted on an oil sep for oil return
samec666 1 year ago
wat oil you using ?
samec666 1 year ago
What a NEAT idea for an old computer case!!!!! REALLY great idea!!!
pomonabill220 1 year ago
I have one set up as a compressor works fine just make sure the crank case has oil and use a fan to keep it cool as well as using a checkvalve inline and A oil catcher as from time to time some oil will come from the discharge line. also filter the suction line to keep junk out of the compressor. mine is on at 110 psi and off 130 psi . compressor from an old 1980's frige used r12 originally.
rick601a 1 year ago
computer ı lıke it :D
atakan196 1 year ago
This hermetic compressor relies on superheated refrigerant coming back via suction line to keep the system from over heating. A refrigeration line set is designed to keep the oil flowing back to the compressor, there is a delivery method in side the compressor to suck oil from the bottom of the compressor and lube the the moving parts. you are setting this compressor up to fail, with out an effective cooling method it will go off on internal overload every time. This is not a limitation.
Goldstarelite 1 year ago
@Goldstarelite I've never had one go off on internal over heat protection, but I guess if you run it hard enough it will. but by that stage it would be best to go out and buy a real workshop air compressor.
oil top-up is a bit sketchy, because there is no sight glass on small comps, but the centrifugal oil pickup is pretty long so it can be over-filled a bit.
and a few tablespoons of oil every few running hours is adequate for a low-hour comp.
Aussie50 1 year ago
@Aussie50
Hi Aussie,
I decided against the oil sightglass and fitted an hours run counter to the pressure switch contacts instead. The counter logs the compressors running time and tells you how much oil to add. I emptied the oil out to check the consumption when the counter showed 5 hrs and again at 10hrs..but so far it hasnt used a drop. I`ll test again when the counter shows 20 hours..in about 2 months time :)
colspyro 7 months ago
You've probably already resolved this but you need a head pressure relief valve that us usually built into some cut off switches. No pump can start with air pressure on it's head so the valve bleeds it off when the regulator stops the compressor.
breezebro 1 year ago
How about using some cooling fans from an old computer or a small a/c condenser fan to blow air over the unit to keep it cool?
craigr13666 1 year ago
@craigr13666 yep, it has fans now, I never posted a update on the finished product.
Aussie50 1 year ago
watch?v=jF4Ta1_-HUg&feature=related
this guy solved your problem.
MrCoryjohnson1 1 year ago
You can try using a non return vale and a bleed off valve. this will lower the internal pressure in the pump to let it restart at a lower pressure. Tank pressure will still remain high.
SGSailing 1 year ago
i also used a new matsushita compressor, but after running for a while, she starts to cook the oil , then blow out smoke.
HDXFH 2 years ago
use older compressors, i use an old kirby fridge compressor from a 30 year old fridge, they will start with a load or not, just makes the compressor wobble a bit, Only drawback is moisture accumulating in discharge
HDXFH 2 years ago
and what is the max pressure psi we can get from them. and can we power them on for many hours. i think domestic fridge comps can not but scrolls can work hours without stopping as in air conditioners. thanks for your answer and nice videos.
azman2150 2 years ago
I have had a rotary up to 600psi, but not a domsetic fridge compressor.
I havn't done many tests on scrolls but they can run for a long time in an air conditioner. but the main factor that contributes to their run time is subcooling.
scrolls are very dependent on cold gas returning from the evaporator to cool the electric motor.
If you were to run a scroll continuously with no subcooling it may overheat and die.
Aussie50 2 years ago
@Aussie50 Hey, Its not sub-cooling that cools the compressor. It is superheat. You cannot readily compress a liquid. when refrigerant is sub-cooled it is in a liquid form, the whole reason for a metering device is to meter the refrigerant into the evap so by the time it exits the evap it has at least 10degree superheat, this is a safety for the compressor to ensure it does not suck back liquid. the refrigerant is sub-cooled when it leaves the condenser. You have it backwards.
Goldstarelite 1 year ago
may i ask that if compressors pumps oil instead of gas, how does not occur problem when they used in cooler units. i mean, they not send oil with the r22 gas? so did a problem in gas cycle? And my second question, if it is possible to ad an oil separator to a scroll compressor, and maybe send oil back to reservoir, possible?
azman2150 2 years ago
most compressors do send a bit of oil through the system as they run, but that oil needs to return to the compressor in order lubricate the compressor over its lifespan.
my theory is that the pressure difference between the suction and discharge side on the Scroll compressor forces the oil to stay in the compressor head. running one at normal atmospheric pressure would drain the crank case in a matter of hours.
Aussie50 2 years ago
THe oil separator is the best idea IMO. just fit a filter to it too, keep any coagulated oil out of the crank case (moisture from the separator may cause problems)
Aussie50 2 years ago
Where abouts do you get those from?
I'm actually wondering if an air conditioner compressor will allow for the duty cycle you are after.
AgentCROCODILE 2 years ago
The compressors I was using were factory surplus, not to be re-sold to anyone. thus I had to destroy most of them and use a couple for experiments.
I ended up using a light commercial compressor, but a reciprocating AC comp would be too big and heavy for the case.
Aussie50 2 years ago
I would imagine that a reciprocating compressor would also incur loads of vibrations (I presume that was a rotary/scroll type in this vid?) unless it is prohibitively large with a good mounting suspension system and/or possibly a lot of cylinders.
AgentCROCODILE 2 years ago
nah the one in the vid was reciprocating. the smallest scroll I have ever seen had to be mounted vertically and was almost as tall as the comp case.
Scroll comps pump tons of oil out when they are used for air. I would not reccomend them.
Aussie50 2 years ago
I suppose they are OK for pumping loads of refrigerants though (which is pretty much what I intend to do) rather than air. The reciprocating ones are not too bad for air and I think they use exactly those in many commercial units too.
AgentCROCODILE 2 years ago
yeah definitly!. if its refrigeration you want then a Scroll will do the job very well!
Aussie50 2 years ago
You reckon I will get a decent one from a new refrigerator? I haven't seen many with scrolls - just recip comp. I would think maybe a "5-star" fridge would have it.
Apparently mattyvt93 has seen some in bar fridges although I've never seen any.
What advantages do recip. comps have over scroll comps?
AgentCROCODILE 2 years ago
I've never seen scroll compressors in small fridges,, only coolrooms.
if your application is only small I imagine a standard recip fridge compressor would work just fine.
Or you could use a rotary compressor from a small airconditioner.
Aussie50 2 years ago
Thanks for that mate. I'll see if I can get a decent air con unit then. Probably a cool-only window AC unit then.
AgentCROCODILE 2 years ago
The correct name is "Klixon".It is a bi-metal switch that breaks both by heat and excessive current.If in doubt, by-pass it and check the current being pulled by the comp. by the plate-load.
Mantsi1 2 years ago
I have a few Kilxon devices from old AC compressors and they are different to what Danfoss use.
the soft starter on this one was simply not designed for short cycles.
Aussie50 2 years ago
Sometimes old refrigeration compressors do leak back through the flappers.I f you fit a standard water non-return valve to the 2 suction pipes, it cancels this problem.
Romaurie
Mantsi1 2 years ago
You might enjoy "Doolin's Troubleshooter's Bible". 1964 edition is the one I have. I'm not very handy but he says you can put a capacitor on a 'fridge motor for increased starting torque.
littlefatzrow 2 years ago
Comment removed
zintoit 2 years ago
what about condensation which would eventually build up in the discharge chamber of the compressor, that can't be good for it in the long run, or if you are using it all the time
HDXFH 2 years ago
the compressor runs hot enough to keep moisture in the oil and manifold under control, the tank is the main concern.
I may rotate it and fit a dump valve.
Aussie50 2 years ago
if you put a check valve and release valve at the compressor when it stops it would depressurize the compressor but not the tank so it can start on demand. i think that should work?
V8Jagnut 2 years ago
an unloader valve would work!, but the compressor valves check the flow so well it wouldn't bleed back even with a check valve.
Aussie50 2 years ago
i know the compressor and a check valve but if you put a unloader valve in you will nee another check valve. you have put a bigger compressor in so im just talking crap now.lol
V8Jagnut 2 years ago
yeah, but it may help sombody thats stuck with a small one like in this vid though.
still dosn't solve the problem of the thermistor overheating though, no way around that.
Aussie50 2 years ago
yhy dose it over heat?
V8Jagnut 2 years ago
I think its actually called a Posistor, the nature of how it works is that it supplies power to the start windings and heats up in the process, increasing in resistance untill there is little or no power going to the start windings.
If you power the compressor down the posistor will remain hot for a while, and thus if I try restarting the compressor whilst it is hot, no power will be delivered to the start windings.
they taught me about these in school but i forgot most of it now :(
Aussie50 2 years ago
why cant you have a relay and 2 of those posistor things and when the compressor stops it changes to the second one for quick start and the next stop it changes to the first one and so on. should be easy to do. :)
V8Jagnut 2 years ago
I found out that air tool oil has all the sameessential properties as refrigeration oil so I'll just use that as oil
HDXFH 2 years ago
sounds like a good thing! I'll keep it in mind for my own systems!.
Aussie50 2 years ago
what type of oil do use to top up these compressors, would you use air tool oil?
HDXFH 2 years ago
if its an older style compressor, fine mineral oil works fine, like Singer machine oil, if its a new one thats designed for R410A etc.. its Polyester Oil, in which case you need to talk to a refrigeration supplier. POE oil is not compatible with mineral.
Ads far as air tool ol goes, I don't see why it would create a problem since we are not dealing with refrigerant compatibility issue.
Other option may be auto trans oil? never tried it but it is made for fine high pressure parts
Aussie50 2 years ago
hmm I wonder if there's a way to modify the starting so it will be more on demand
coolbluelights 2 years ago
I guess you could try a small start capacitor and conventional starting relay, but I don't think the start windings are designed for high impulse starting current.
I may try that today with a HST starter on the LST comp
Aussie50 2 years ago