Tip & How-To about Heating & Cooling

To check compressor windings

Power off. Remove the terminal clips and the check C S R with ohms meter.
Check Ohms two ends with CS, CR & SR . SR should read the total of CS & CR. Then your compressor is o.k. It should not read anything ( even 00.00ohms ) if you connect one lead with any terminal and another with grounding. If it reads, your compressor is grounding.

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Samsung fridge sr-l709evs when it get cold it stop and it does not start again untle i remove the plug and put it again in electricity


Fridge not starting? CLICKING? FIRST ALWAYSCHECK FORpower at the outlet,checkfor 120 volts.

MAY HAVE A BAD START RELAY OR CAPACITOR ON THE COMPRESSOR , CAN BUY A INEXSPENSIVE 3 IN 1 HARDSTART KIT AND BY PASS THEM , NOT THAT HARD TO DO, COMES WITH INSTRUCTIONS> BY THE WAY DO U HEAR ANY CLICKING SOUNDS FROM COMPRESSOR? BUT U MAY ALSO WANT TO CHECK UR COLD CONTROL THERMOSTAT IF IT GOES BAD U MAY GET A NON START ALSO HAVE IT CHECKED FOR PROPER VOLTAGE AND OHMS RESISTANCE WHEN IN THE ON POSITION
A BAD DEFROST TIMER CAN SHUT DOWN COMPRESSOR HAVE IT CHECKED WITH MULTI METER.

to check the defrost timer, u can get by and test manually by placing a small screw driver into the tiny slot or hole underneath the timer and turn slowly clockwise till u hear 1 click. this will engage ur defrost cycle in about 15 minutes u should be able to come back and feel the heat in freezer as it melts the ice providing ur terminator is not bad?
Another way to test it is with a multi meter. Remove timer it from fridge and you will see 4 prongs numbered 2,1,4,3 in that order. Place ur meter prong on prong 1 & 3 (if your fridge has a capacitor wired in series with the windings, then u check for micro fares rather than OHMS) If u cannot confirm this test, still try the next.
Take ur meter prong and connect to prong 1 & 4, it should read resistance or ohms ( closed) now remove prongs and place on prong 1 & 2, this should now read infinity or open (no ohms) now take a small screwdriver place it in the tiny hole or slot under the timer. Turn it clockwise slowly till u hear 1 click. Now ur 1& 2 should read closed ( showing ohms or resistance) now place meter prongs on 1 & 4 and you it should now show open ( or no resistance - no ohms) this is how u know ur timer is good, Remember when testing for ohms ADJUST meter to use a high ohms rating in the thousands as the resistance is very high in OHMS. And adjusting to low ohms rating may give a false reading or not show the proper resistance..


AT TIMES YOU MAY HEAR THE COMPRESSOR CLICK OFF AND ON OVER AND OVER. Signs of a bad start relay or capacitor. Check with an OHMS meter for continuity (ohms) and voltage, capacitor can be checked for Microfares.
To check ur compressor with multi meter:
Disconnect and remove the relay and capacitor from compressor, somes located next to compressor in a casing.

You wills see 3 prongs coming out of compressor. 1 goes to ur srtart winding, 1 goes to ur run winding and the center goes to ur ground.

Place ur meter connector or prong on the start prong and the other on the ground (center prong) take note of the reading in OHMS for example 5 ohms.
Next place meter prong on run prong and the center ground prong agin. Take note of the reading in OHMS. Example 4 ohms

Next place meter prong on the start prong and the other on the run prong, now take note of the reading example 9 ohms. Now match the total of this ohms test with the total of ur two separate test. 9 ohms, if they match ur ok give or take 5 percent plus or minus. One more test to make to test of there is a short in compressor attach meter prong to ground prong and rub the other end of meter prong to metal ( scrape the metal clean of paint and test on metal surface not painted surface. If it shows continuity or ohms , u have a short in ur compressor. It should show infinity

Mar 18, 2015 | Samsung Refrigerators

1 Answer

flashing ch21


Ch21 refers compressor runs high current. Due to
1. Condenser coil dust blocked- Clean it.
2. Condenser fan motor less rpm or struck- Replace capacitor or motor.
3. Compressor windings weak- Check by ohms. If single phase, the ohms of SR should be the total of CS & CR. If 3 ohase all winding ohms should be equal (1 &2, 1&3, 2&3). If not replace compressor.
Thanks and hope helpful.

Jan 27, 2011 | Comfort-Aire HMC18AS-1 Air Conditioner

1 Answer

I did the ohm test on the compressor and got reading of 4, 9 & 12 do I try the relay kit


Normally, ohms of SR will be the total of CS & CR. Seeing your ohms reading, compressor is. o.k.
Better replace relay kit and check. After relay replaced, fridge not cooling,check for gas leak.

Thanks.

Jan 22, 2011 | Refrigerators

1 Answer

Our Friedrich Floating Air system keeps throwing the breaker. Worked fine for 5 years, now can't get it to stay on.


Check compressor is taking correct amps, if high amps due to capacitor weak, replace it. And also check for any short circuit in wiring.That is also the reason for breaker tripping.
Finally,
Remove power. Check compressor terminals after removing wiring, When your ohms read something between any terminal and grounding, it's understood that compressor grounded. Replace it.
If windings reading should be : SR should read the total of CS and CR (C=COMMON, S=STARTING,R=RUNNING). If the total is higher or lower, the compressor winding is weak. That time it takes higher amps and breaker get tripped.
Hope helpful?

Jan 21, 2011 | Friedrich M18CF Split System Air...

2 Answers

Fuse keep blowing out before it come completely on. Red light links five


Due high pressure or over current in your a/c.Check with amps meter and also loose wiring or burnt wiring and rectify it.
Power off, and check compressor winging with ohms meter. CR, CS, SR. The reading of SR must be the total of other two. Check with one terminal and ground, if it reads anything, your compressor is grounded. That is one of the main reason for fuse blown. Thanks.

Jan 12, 2011 | Heating & Cooling

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