Joe Lee

If you have an Automatic Transfer Switch, and it is misbehaving, it could be making the ‘thud’ sound. Perhaps place your hand on the case of the ATS and see if you can feel it.

Great project! I really need to follow your lead. I appreciate your willingness to document this for all of us.

Hello all! I have been in search of a replacement switch for the electric element side of my Aquahot for some time. Called Eaton and they don’t have a replacement. Any suggestions? Thanks! Joe

I don’t know where to take an amp reading to determine my charge state. Could you please advise? I do have a multimeter with an AC 400 amp clamp.

Ok, smart people! Please let me know what you think about this. I have discovered that the 3 copper tubes as shown in the attached picture (2 in the foreground and 1 behind and they are marked with silver foil tape) are not nearly as cold as the same copper tubes on my other a/c unit as I’m running the unit in cooling mode. what does this mean? Thanks! Joe

Thanks Tom! Here’s where I’m at: 1) I did replace the filter with a new appropriate filter material. 2) I have inspected both units. I didn’t see anything that looked out of place and both units looks alike. 3) My first step was to clean both units with a coil cleaner recommended for RV A/C units. No change and they didn’t see too dirty. My Rig spent the first 18 years of its life inside. 4) I have the install manual and I believe I have completed those steps. 5) Your next idea is to call Lippert. I did call Dometic. Would Lipper be a better source? As I’m not a pro so, Dometic wasn’t very helpful. Today, I replaced the PTCR (Postive coefficient thermal resistor). My short cycle times changed from the compressor being on for 50 seconds to about 5 mins. Progress but must not be the solution. Thanks for the heads-up on the front unit being in trouble as well since the Delta T is too great. Seems it may be time to give up on the repairs unless a call to Lippert or a professional will help. What do y’all think? Thinking of adding a Remote Thermostat to the Rear Unit that is short cycling. This would eliminate the thermostat at the main thermostat unit on the wall. Also, thinking of replacing the thermostat and control board next. Thoughts if this is a waste of time and money? At least isn’t getting cooler in Amarillo TX! Hoping to be out of here in the next month.

My thanks to everyone for sharing their time and expertise. Well, within a day, my Dometic Penguin started short cycling again. The compressor will only stay on in ‘Cool’ mode for about 50 seconds. However, the ‘heat pump’ mode works very well. I’m going to retest all the components and use the advice already given. Here’s a few details on running the unit in Heat Pump mode: I ran my Penguin for over 60 mins and, using my Pocket Thermometer (thanks Tom!), I’m showing a temperature Delta T of 35 degrees F. Intake temp = 92. Return temp = 127. Man - it’s hot in my bedroom! The compressor remained on for the entire test for over 60 mins. The unit didn’t Short Cycle a single time. Does the Heat Pump working well suggest anything else I should test/replace? And, don’t all the components work the same way, just reversed to create heat or cold? Is there a way to test to Control Board? Thanks for all the help!

Well Folks - I can’t believe the solution for my A/C short cycling. I removed the filter material I was using and the short cycling stopped. Kinda embarrassed to share my solution, but perhaps it’ll help somebody else one day. This filter material was about 1 inch thick. I just order some that is only 1/4 inch thick. Seems to have helped. My A/C unit is now cycling about 3 times an hour. The temperature has not cooled down to the temperature that I have set on the thermostat, but this may be normal. Bottom line: the compressor will stay on for about 20-25 mins, then cycle off for about 4 mins, the turn back on. It’s not freezing up, so I can’t determine why it’s cycling. But I’m much better off!

Hey Gary! Thanks for sharing your time with me. I did test the thermal overload with and without the compressor running. Both situations test positive for continuity. I also swapped out the thermal overload between my front and rear a/c’s. No change in my short cycle problem. I’m done fighting today. Thanks for all the support! Joe

Thanks for the idea! I have attached what I believe is the Thermal Overload. If this is the correct part, I did test it for continuity and it did have continuity. So, could it still be bad?

Question for someone what knows freeze sensors. I measured the ohms for my rear freeze sensor and I got a reading of 22k. The local RV shop thought it should be 32k. Both my front and rear freeze sensors measured about 22k. So, I’m thinking these are good. I’m needing an expert to weigh in. could this cause the short cycling issue? If so, I’m just going to buy 2 new ones!

Hi Gary - the short cycle lasts for about one minute. I have tried the fan in auto, high and low to see if there was a difference. No change. The compressor constantly short cycles at about 1 min. The only time I found the short cycle to change was after I ran the heat pump for about 10 mins. After that heat pump cycle, the A/C did stay on for about 8 mins. Then, it was back to the 1 min short cycle.

Hi! I’m still struggling to figure out my Dometic penguin rear AC that is short cycling. Today I tested the capacitors. My run capacitor is a 20+10. (If I’m reading it correctly!). The 20 side is reading at 18.6 2,10 side is reading at 10.29. Could someone help me determine if this capacitor is good with these readings? And, could this capacitor have any impact on the short cycling? Thanks everyone and happy Friday!

Hi Coach J - wow. Hoped I had found a problem. It does sound like the opposite of what you had. Hoping I had found a simple fix. My continued thanks for this group! I will continue the hunt for the short cycle problem.

Hello All! I have been using this topic to help me diagnose my A/C problem. Thanks to all for documenting this so well! My issue is with my rear Dometic Penguin (2002). The unit is ‘short cycling’. I have been using the attached Troubleshooting Guide and discovered what I believe is a missing Remote Temperature Sensor. It is WHITE as shown in the Guide. When I traced the wire from the control board to the sensor, I discovered that the sensor was missing. See Picture. It would appear someone in the past removed this sensor on purpose. The 5 button thermostat control is located in the bedroom. Would anyone know if this sensor is required? Seems like it! Could this missing sensor cause the ‘short cycling’ problem? My front A/C unit has this sensor and it is working properly. Thanks for your thoughts!

Tom - thanks for the extra tip on heating the water bay. I am concerned about the possibility of very low temps. I haven’t been in cold weather yet so I’m sure it will present new changes. would you place the order trouble light in the Aquahot bay or the sewer bay?

Hello All! My daughter is getting married in Dayton, OH on 2/3/24 and we don’t know anyone in town. I have been looking for a place close to the University of Dayton and, so far, I’m only seeing places with power outside of town. Would anyone have an idea of a place I could ask to stay at? Since it will be COLD, I would like the luxury of power! But, I’m getting desperate. Thanks! Joe

Thanks for the ideas and I did identify the wires. #1 - OEM Water Pump #2 - OEM CO Detector #3 - 5 AMP Slide Out Controller. Seems that wires #1 and #3 were were cut prior to my fridge removal. Both the water pump and slide out controller are powered separately and are working fine. I will repair #2 and return to service. I will cap off #1 and #3 so as not to have exposed hot wiring and remove the OEM fuses that powered #1 and #3. As voltage is still present on one side of the wire, I’m thinking that power is being back fed as the OEM wiring was never disconnected. My thanks to all! Now, back to my previously scheduled fridge replacement. I think I’m going to have to deal with the fridge sticking out in my hallway. Hoping I get used to it quickly.

For those helping me with my refrigerator replacement … thank you! Today, I’m hopeful someone has worked on this wiring before and can help me identify it. I have an 02 Windsor with a fridge bay on the pass side between the kitchen counter and the bathroom pocket door. I have removed the NorCold and discovered cut these cut wires. These were possibly cut when I removed the fridge but the cut wires look dirty, as if they have been cut for a while. And, these wires are hot. I have pulled every DC auto fuse that I could find all over the coach. (Fuse Panel in bedroom, Fuse bay under drivers window, Outside Bay with house/chassis connections, fuses in Aquahot bay) I have identified only one of these wires. It’s the large gauge wire with the tag stating F15 - water pump. F15 is the fuse position in my DC panel in the bedroom labeled Water Pump. I have determined that the water pump is NOT powered by this circuit. I can’t figure out what is. The only switch that hasn’t worked since I purchased this coach earlier this year is the remote start switch in the bedroom for the genny. I took 3 pictures while I zoomed in it the larger wiring loom with the cut wires. I was able to cut power to the tagged F15 wire by removing the fuse. However, 12 v is still present at the same gauge wire coming up through the bottom panel. this is no power at the small gauge red wire with the black tab in my fingers. There are 3 red wires coming up from the bottom panel. 2 are cut and one is damaged but has some connection. All 3 wires have 12v and I can’t figure out where these wires are getting 12v. I have looked at the wiring diagrams but can’t really determine what is what. All ideas are appreciated. Next, I plan to remove the bottom panel, lower it and make space for a residential refrigerator. Hoping I can lower the panel without having to disconnect all these wires!

Update on my Norcold 1200 problem: 1) With all your valuable ideas, I’m ditching the Norcold and getting a residential refrigerator. 2) I have removed the old Norcold. That was as much fun as you would expect. 3) Now, I’m going to have to rebuild the refrigerator bay by lowering the original shelf. Will have to move plumbing and water lines for sure. 4) Tomorrow, I’m going to decide between 110v residential and 12v dc RV. Seems the industry is pushing towards 12v DC. Does anyone have an opinion on the 12v refrigerators? They are more expensive and I can only see the value of running the refrig without an inverter. Are there other benefits? Thanks for the advice. I got in too much of a hurry and the advice to slow down was helpful. I’m going to connect AppliancesConnections.com tomorrow for sizing as recommended. My thanks to all!

I just found a NorCold Ultraline 12 cu ft refrigerator at Camping World. As I’m in a hurry to fix it, I’m taking a look because the parts dept said it was a direct replacement. (Of course, they didn’t specify the dimensions on the website). Has anyone had any luck with this unit? Of course I’m very concerned that this unit will still have all the past issues of my old 1200 NRIM. The staff at Camping World either didn’t know or wouldn’t say. Thoughts? Cbr046 - Bob, I really like the mini fridge for drinks on the go!

I just found a NorCold Ultraline 12 cu ft refrigerator at Camping World. As I’m in a hurry to fix it, I’m taking a look because the parts dept said it was a direct replacement. (Of course, they didn’t specify the dimensions on the website). Has anyone had any luck with this unit? Of course I’m very concerned that this unit will still have all the past issues of my old 1200 NRIM. The staff at Camping World either didn’t know or wouldn’t say.

It’s my turn to be dealing with a failed Norcold 1200 LRIM. Just read all the insights from this topic. I didn’t see any 2023 comments. I’m a full-timer and enjoy boondocking. Does anyone have any new recommendations for me as I deal with this issue? Thanks! Joe

SUCCESS! My many, many thanks to each of you for helping me out today. It was a combination of each idea that solved my problem. I tried to mark each of your comments as the ‘solution’ but the system wouldn’t allow more than one solution. In the end, I was able to get the weight off of the gears with the jack. I was able to see the gear didn’t have enough clearance to ‘jump’ a gear so I removed the cotter pin on each side of the gear. There was enough play to allow me to move the gear to the side, rotate it and reposition it. It took me a couple tries to get the timing right, but it now works! Thanks to each of you for taking time out of your day to help out someone you haven’t even met. That is truly amazing in today’s world! I’m glad to have you as friends and I hope to cross paths one day! Joe

I’m on my way to Lowe’s/Walmart to get a bottle Jack and a 2x4. I’m planning to Jack up the forward drivers side as that is where I believe the sound/tooth jump occurred. I plan to raise the slide, then push the slide in to correct the tooth jump. Any suggestions on how much to move the slide? Do I just measure the slide until the slide is square on both forward and rear sides of the slide are the same distance to the side of the coach? And, how much do I extend the slide for this repair ?