a/c compressor doesn't run

[billcrews81]

Originally Posted by 2005gts

thank you

i thought about the capacitor, but i have learned the hard way that making too many changes at once can cause confusion about what may/may not be the problem/solution.... as previously noted, SoftStart tech support and I restored the wiring to oem configuration and the compressor starts and runs, so the softstart module is known bad; is the capacitor weak, i don't have a clue (and don't know how it would act if it is..., i only know that the compressor runs now); I/WE will have to wait until a new module is installed to see if there are any other problems.

Bill

Bill thanks for posting this thread. Good helpful info here.

[IamProStreet]

Glad you got it figured out!

[2005gts]

thanks to EVERYONE who has contributed to the resolution of this problem



Bill

[2005gts]

Originally Posted by IamProStreet

Glad you got it figured out!

Bill

[Aussieguy]

Hmmm Interesting photo ..

In not a electrician, so just wondering what the 2nd black capacitor is used for .... is it possibly a HARD start ?


The larger capacitor looks like it is a combined fan and compressor



did you show the capacitor photos to the technician?

[2005gts]

Originally Posted by Aussieguy

Hmmm Interesting photo ..

In not a electrician, so just wondering what the 2nd black capacitor is used for .... is it possibly a HARD start ?


The larger capacitor looks like it is a combined fan and compressor



did you show the capacitor photos to the technician?

i was told that the little black capacitor is the start capacitor, the big silver one is the run capacitor. now you know everything i know..., including that it is apparently a problem with the SoftStart

Bill

the picture above was taken before the restoration of the oem wiring. there is still a red & yellow connected and a black wire connected to the large capacitor that go to the SoftStart. note that in that picture there is a wire missing that goes to some gadget that in turn goes to the big capacitor. the red wire from the black capacitor is the wire i had to make and reinstall (i was told at the time of the original installation that it wasn't need, so i tossed it... also, this picture shows the red/yellow & black wires still connected, they have been disconnected)

[Larry-NC]

What I'm used to seeing (all A/Cs aren't necessarily this way) is that the silver capacitor package with THREE terminals contains both the Start capacitor and the Run capacitor for the compressor, and the black capacitor with TWO terminals is the start/run capacitor for the outside fan.

[2005gts]

Originally Posted by Larry-NC

What I'm used to seeing (all A/Cs aren't necessarily this way) is that the silver capacitor package with THREE terminals contains both the Start capacitor and the Run capacitor for the compressor, and the black capacitor with TWO terminals is the start/run capacitor for the outside fan.

could be, dunno; all i know for sure is it goes to/through a little gadget with a funny name you can see in the picture and then on to the silver capacitor..

Bill

[2005gts]

it appears that the "gadget" is a:

Dometic 3310731009 AC PTCR Positive Temperature Coefficient Resistor

https://www.achrnews.com/articles/87...cient-resistor



Bill

[Aussieguy]

looks like a hard start kit was added to the a/c
I would get a hold of the tech and let him know your system has a hard start and will that make a difference to their instructions


I'm betting the new soft start has to be installed on the larger capacitor
https://getrvparts.com/dometic-33118...ard-start-kit/

[2005gts]

Originally Posted by Aussieguy

looks like a hard start kit was added to the a/c
I would get a hold of the tech and let him know your system has a hard start and will that make a difference to their instructions


I'm betting the new soft start has to be installed on the larger capacitor
https://getrvparts.com/dometic-33118...ard-start-kit/

nope. the tech guy knew all about the PTCR without me telling him because he told me to reconnect the wire, so i "presume" that this was standard with this particular model. when the softstart was originally installed i was told to disconnect the small capacitor's wire from the PTCR. OR, maybe when i was describing everything during the initial install he knew from my description what it was and told me to disconnect it.... (i've slept a few times since then, and none of them were at a Holiday Inn Express)

maybe someone added it at some time or maybe it was original... dunno

the only reason i added the SoftStart to begin with was a discussion on this forum 'way back when' about using smaller generators or that a softstart mechanism was better for the health of the a/c... so, being a guy that likes to try things i ordered one...

at the price, i thought it was a 'forever' thing and now disappointed that it isn't


Bill

[Bob K4TAX]

There are two different items, similarly related but vastly different in actual operation and performance.

The Soft Start system is just that, makes it easy for the power system to start the compressor or motor. It reduces start-up current.

The Hard Start system is for compressors or motors that start under load or for some reason are difficult to start. It really kicks up the current in the starting process.

I suppose one could say these systems are opposite in operation with regard to starting a compressor or motor.

Bob

[2005gts]

a refrigerant compressor is always is preloaded at an equilibrium pressure on the hi and lo sides when at rest/before startup, maybe in the 70ish+ pressure and then upon startup it can go as low as the 40s and highs of 200ish. i can understand the surge of amps needed to get it started and get to its hi/lo operating pressures.

i can only guess that a soft start system cause the compressor to do a slow roll turnover/start.

Bill

[2005gts]

received the new softstart unit yesterday and installed it today with the help of a Softstartrv tech support person (great people). the newer unit is physically smaller and a bit more installer friendly with fewer cuts and splices.

i am COOLING it now....


Bill

[IamProStreet]

Originally Posted by 2005gts

received the new softstart unit yesterday and installed it today with the help of a Softstartrv tech support person (great people). the newer unit is physically smaller and a bit more installer friendly with fewer cuts and splices.

i am COOLING it now....


Bill

Cool!!!

[2005gts]

not wanting to start another thread, maybe folks will see this here...

now that the a/c is working; is there a GOOD reason to change out the analog thermostat to a digital one?

Bill

[Bob K4TAX]

I always have to ask the questions:

(a) If it is working why does one need to change it?
<better looking? <more reliable? <easire to read or set?

(b) What does one expect to achieve or gain by changing it?
<better efficiency? <better performance? <better accuracy

My general rule is; "if it is working, don't try to fix it".

Bob

[Larry-NC]

Originally Posted by Bob K4TAX

I always have to ask the questions:

(a) If it is working why does one need to change it?
<better looking? <more reliable? <easire to read or set?

(b) What does one expect to achieve or gain by changing it?
<better efficiency? <better performance? <better accuracy

My general rule is; "if it is working, don't try to fix it".

Bob

The failure rate of a mechanical thermostat is far lower than that of an electronic thermostat.

[2005gts]

i agree: "if it ain't broke, don't fix it".. but sometimes it's hard to tell if something is only 'wounded' or just tired...

i just wondered if a digital thermostat might be an improvement other than having a digital display of the temperature and some buttons instead of slides.

and then a review of the reviews on Amazon of a replacement Dometic analog similar to the one i posted a picture of showed some folks were going to replace their digitals with an analog because the digitals were problematic...

so, thank you

Bill

ps: how come my pictures post sideways?

[Aussieguy]

Originally Posted by 2005gts

ps: how come my pictures post sideways?

was your computer/camera level when you uploaded?
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when you take a picture especially on a phone... they put orientation information into the pic.
That info is based on what the camera thinks you want...

In the old days if your turn your camera upside down... you get an upside down pic... the auto orientation thinks you want it the other way up.

you can turn off the automatic stuff in your camera settings
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Web browsers use that info to make sure the picture is right side up in a web page.

The same picture ... when you click it to view only the picture
It is now no longer inside a web page and the orientation is different.