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AlexM

3-1 Start Kit, Fire Danger? Do techs use them regularly?

22 posts in this topic

Someone told me recently that they never put hard start kit on a compressor becuase it can damamage the compressor and is a potential fire hazard.  I have used them for a couple of days while the factory relay and overload could show up.  I did install one perminantly on a garage fridge. I would love any thoughts on the matter.

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Need appliance parts? Call 877-803-7957 now!

DO NOT use them. If the compressor will not start with the factory OEM relay, overload, and run capacitor, it's time for a new compressor or a new refrigerator.

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They draw a slightly higher amperage ... and so manufacturers don't want them left on.  I really can't see how it would be a fire hazard though.  I use them in the same way Alex does - get the customer going while I get in the correct start device.  I've also put them on the 30 year old 'beer fridge' in the garage to try to get a bit more life out of the old units as the compressors fail.  I've never seen a 'fire' from one of them.  

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I see no problem using them in certain situations. Short term fix while customer is able to get another fridge.Especially with older machines or those with limited electronics, so long as you advise the customer of the risks and get a waiver. They can also be useful when a pin is broken on an otherwise working compressor. My father's 2007 SxS had a burned out relay that melted and destroyed one of the pins. I put a 3 n 1 on it almost 4 years ago and it hasn't skipped a beat.

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Are you talking about a 3&1 or a hard start ?

these are not the same thing

 

A  3 & 1 is used without any other start parts , just hook power to it and connect the 3 compressor pins to the other end of it and go 

 

A hard start is used mostly on AC units to get a compressor going , that without it would just sit there and draw Lock rotor amps and never start , it is used  with the OEM cap and overload (if external)

 

with a 3&1 there is no problem leaving it on , but i have noticed lifespan of the 3&1 is shorter than OEM start parts ( i have seen them go bad in less than a year)

 

with a hard start , no problem leaving it on ether , but make sure it's not sized to big , if so i have seen compressor failure , out of the blue when the wrong hard start is installed

 

 

bottom line is use both in a pinch , if you can get the oem parts , do so , if not .......that's life

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I've been using P/N RCO810, is this a Hard Start or 3&1 and what the differences

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What about a compressor analyzer? I've heard they are expensive. At the end of the day are they worth it?

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Supco's 3n1 for fridges are hard starts as well since it sends more starting power to the compressor. These are the ones we usually think of when we talk about fridge hard starts They, such as the rco41 and rco81are advertised as 3n1 hard starts . There are generic relay all in one devices that include relay, overload and capacitor such as supco's pro41 and pro81 but they are not marketed as hard starts.

Alex, the 3n1 you are using is for smaller compressors found on mini fridges. They send less hp than needed for a standard compressor. If you are using those on larger compressors then you probably could have used the pro41 generic push on start/relay and avoid any issues presented by the use of an unnecessary hard start. Remember, with supco, the smaller numbered versions ie pro41 uco41 etc are for normal size fridges while the larger numbered ones ie pro81 uco81 are for mini fridges.

What about a compressor analyzer? I've heard they are expensive. At the end of the day are they worth it?

The Samurai has one but says he rarely uses it. He prefers the use of a megger. And as much as I love gadgets with blinking lights and stuff, this is the only reason I haven't bought one. Hmmmm... Did i say blinking lights and stuff.... Dials and buttons and is called an analyzer? How cool is that... maybe I should rethink this. Edited by DurhamAppliance

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Are you talking about a 3&1 or a hard start ?

these are not the same thing

correct ...

Any fire danger would be from the questionable / "bad" Compressor

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I think this is just a terminology thing.  In my neck of the woods, a 3n1 is nearly always referred to as a 'hard start kit' or just a 'hard start'.  I know this is different than the big AC hard starts - but this is the term used where I am.   The capacitive kick and run from a 3n1 is definitely more than OEM stuff - so it will often start a compressor that the OEM start device cannot start - in that way, it is a 'hard start' device.  

 

Any fire danger would be from the questionable / "bad" Compressor

Agreed.

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... and, there's the standard generic solid-state Start Relays ...

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 Anything that says rco(relay capacitor overload) is a hard start. It puts a start capacitor( most refrigerators use run capacitors, for filtering, not start capacitors,for starting) in series with the start winding and raises the voltage, which raises the current, thus starting the tight compressor. The ro81 is a generic relay overload and works just fine, espescially when the original costs so much the customer does'nt want to pay 100 dollars, as in a recent freezer I worked on. I also worked on a frigidaire side by side with a relay cost of around 175 dollars. I talked to the refrigeration specialist at supco and he said just make sure you size the relay properly for the unit. The rule of thumb he gave was under 10 cubic ft ro81. Between ten cubic ft and 22 cubic ft use ro41. Horse power has become a hard value to determine anymore. It is measured differently today than in the past. Remember if the compressor is tight it could run a long time with an relay capacitor overload (RCO) unit, but do not over size it, and be honest with the customer.  

 One last thing, these use a thermal overload, (rco and ro) so if the compressor is drawing to much current and creating to much heat the thermal overload is designed to open and shut the system down. I use them. I am also completely honest with the customer.

 Another thing is the 134a compressors are not built as well as the older compressors so they (the windings) may not hold up to higher current as well.   

 Sorry for being so long winded but I struggled with the different opinions on these parts and did the research. I hope this helps

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... compressors are not built as well as the older compressors

also differences in quality between Embraco and Tecumseh ... old and new

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 ..

...The ro81 is a generic relay overload and works just fine,...

...... I use them. I am also completely honest with the customer.

Our posts are pretty much in agreement but I like to use the pro41 as opposed to the ro41.  the P stands for "push on" as oppose to the ro style which is connected like the hard starts.  I keep them both on my truck and never considered them hard starts.I think the customers accept the push on type easier as it doesn't have wires everywhere.. I have been using these  for over 3 years and  never had a problem . As I think about it, I should have used the ro41 on my father's fridge with the broken pin instead of a hard start. So now I have a new internal rule...use ro41's when the compressor is good but has a broken pin and use pro41 in all other cases when a universal relay is okay.

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now i am lost , a broken pin is a broken  pin , the compressor is toast !

 

how can you use one type of relay over another to start a compressor with a broken pin ?

 

If the common is missing , you run it through start and run ?

if run is missing , you start and run it through common and start ?

if start is missing , you start it and run it through common and run ?

Call me dumb but in 39 years of this stuff i have never heard of this !

 

I have replaced dozens of compressors over the years that one pin was so burned up there was no saving it

 

please bring me up to speed , what the heck are you guys talking about ?

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What about a compressor analyzer? I've heard they are expensive. At the end of the day are they worth it?

 

 

Not worth the money or trouble.  You can do a better job yourself with a good ohm meter and a megger.   Use the ohm meter to check the winding resistances (especially critical with new variable speed compressors) and use the megger to check for high resistance leaks from windings to ground, like ahso...

 

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now i am lost , a broken pin is a broken  pin , the compressor is toast !

 

how can you use one type of relay over another to start a compressor with a broken pin ?

You are assuming a missing pin when I was talking about a broken pin. You never had a pin that was broken to the point where you could not stabilize a relay on a compressor but enough remaining to where you can attach a wire from a hard start or ro41? I've had them where when you attached a relay it would eventually fall off due to one of the pins broken in half. I tried using tape, wire ties and even glue. You know the old saying where if you remove one leg from a three-legged stool the stool will fall? Well the same thing will happen if you remove 3/4 or even 1/2 of a leg.

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DurhamAppliance wrote : "You are assuming a missing pin when I was talking about a broken pin. You never had a pin that was broken to the point where you could not stabilize a relay on a compressor but enough remaining to where you can attach a wire from a hard start or ro41? I've had them where when you attached a relay it would eventually fall off due to one of the pins broken in half. I tried using tape, wire ties and even glue. You know the old saying where if you remove one leg from a three-legged stool the stool will fall? Well the same thing will happen if you remove 3/4 or even 1/2 of a leg."

 

 

 

we call them damaged pins , there is still something to work with

 

broken is sort of fatal , unless you do the old brazing rod and torch , and tack it back on

Edited by Cactus Bob

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I use them, when the cust can't afford a sealed system repair, but can't yet afford a new fridge, If the compressor has LRA amp draw I just condem the compressor. I have seen in the past where a compressor shorted to ground, burned out an adaptive defrost control, due to having a 3in1 put on. In my neck of the woods, I always check for windings to ground before installing a 3in1.

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we call them damaged pins , there is still something to work with

broken is sort of fatal , unless you do the old brazing rod and torch , and tack it back on

I have to agree, "damaged" is probably a more accurate description. I apologize for the confusion but I think most of us are saying the same thing but using different words.

 

Edited by DurhamAppliance

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  3-N-1 kits....................Do I install or Do I not install...That is the question...............This is like.................  Democrats, sit over there and Republicans  sit over on that side..........Gun owners over there ....Anti gun, sit some where else................Martinis, Shaken not Stirred................I install one as needed........After testing the compressor with a Supco, Meg-o-meter..........Measure the start amps and the run amps...............Test with a factory start pak, ( got a box of used, known good paks ).....AND it still will not start.......I install a Supco P/N RCO 810.. ...(or the Supco with the run cap wires, forgot the P/N )............. The customer it told that the compressor is on 'Life Support'.......... Gives them time to save for a new refer ....Around here the old one is move to the garage and is now a 'Beer-N-Bait'  cooler...................... Did a call a few days ago, refer leaking water..Spun the unit around to fix the water line and what do i spy????  A 3-N-1 pak I installed 3 years ago... ( fixed at the home but now at her beauty shop ).........Gotta have the 'Big Kahunas' to put your name and date on the back of the unit.......

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