Bill R

Thanks @Georgia Mike. My bad run capacitor does not look anything like yours and only 40 + 15 uF. As I suspect previous repair replaced with what was available and not what is specified. @Ivan K My older unit is a reciprocating compressor and like yours requires 20 + 10 uF. The newer front one is a rotary compressor with different specs. Lesson learned: Always look at fan motor and compressor name plate to confirm run capacitance requirement. What is existing may not be correct.

To the point about design specs, and being an engineer myself, I decided to dig further on the compressor for the front unit that I just replaced the run capacitor for. It is an LG GJS134C rotary fixed speed compressor. I was able to download the specification sheet and it states that the run capacitor should be 55 uF. WHAT? What was there was 40 uF. Now I am beginning to wonder if this was not a factory installed run capacitor and someone just decided to put in whatever closest available capacitor there was. An unfortunate common thing done by AC techs, not all. I also know that a too low rated run capacitor can overheat. Maybe that is what happened here? And another interesting point is that this LG compressor does not require a start capacitor. The wiring diagram of the control board actually say optional. I am going to look to see if there is actually a start capacitor. I don't recall seeing one now that I think about it. I looked at the fan motor plate and it does say that the run capacitance is 15 uF. So it looks like I need to go purchase a 55 + 15 uF run capacitor based on the engineering specs of the compressor and fan motor.

@96 EVO, @Tom Cherry, @myrontruex, @Ivan K, and @jacwjames. You all nailed it, but I can't pick all of your comments as the solution. I did the quick capacitance test today and the run capacitor was shot. Both the fan and compressor were 0 uF. Made a run to the local appliance U-Fix-It shop and got a new and a spare run capacitor. $46 total. Installed and now she is running and quieter than ever. Even seems to blow more air than before. So I have a couple of questions about these run capacitors. 1) Do the run capacitors just die at once, or is there a slow degradation that will slow performance of the unit over time? If it is a slow degradation then a quick capacitance test every so often during PM might head off a problem. 2) Both my units are 13.5K BTU Penguin II Heat Pump. The rear one is older than the front that had the problem. When I looked at the rear unit run capacitor the spec on the label was 20 + 10uF. But the one I had to replace had a spec of 40 + 15uF. Why such a large difference? Both units look nearly exactly the same except the older unit compressor is horizontal and the new one up front is vertical. Does it really matter about how much difference there is? If I had done a swap test would the 20 + 10uF capacitor have been able to run the front one? Thank you for helping me not only fix the issue, but learn more in the process.

@JeffM31 Do you feel like your coach has more power with the straight pipe?

@96 EVO Hey Ben. Yeah I am referring to the run capacitor when I was referring to "capacitor". Feeds both fan and compressor. Thanks. @Tom CherryThanks Tom for the video. Seems to be my exact scenario. My VOM does have capacitance. So it looks like I know what I will be doing tomorrow. I'll report back what I find. I am hoping it is as simple as the run capacitor, and thank your for the quick comments.

Yesterday while running both front and back A/C's, (Front 13.5K Penguin II, Rear 13.5K DuoTherm) both cooling very well, been running for about 2 hours, all of the sudden the front A/C shutdown. Checked breaker, was good. Checked power at the unit, have power. Checked thermostat, all good. I went on top of the coach to look briefly at the unit, placed my hand on the cover, and it was very hot. The back A/C cover was just warm. Today, back on top of the coach, I pulled the front unit cover off, and using my wireless Micro-Aire I turned the fan on low. Nothing. But reached in and spun it, it started right up. Shut it off, won't come on. Spin, it starts to move again. Below are other observations and voltage readings. I am fairly certain that this is either a capacitor or fan motor issue, or both. - fan does not start until I spin it - fan will stay spinning when going from hi to low speed and the reverse, it only will not start up after I shut the fan off completely - on low speed the fan seems to run normal - on high speed the fan makes an oscillating humming noise and is loud - there does not appear to be any difference in fan speed going from high to low - inside the coach, air is barely, and I mean barely, coming out of the vents, on low or high - compressor will kick on, but it is really loud after just a minute, and makes an oscillating vibration noise - Temperature of the fan motor casing unit was 130F, hot to the touch, the rear unit fan motor only gets up to 108F - The compressor casing temp was up to 196F, the rear A/C compressor only gets up to 140F - Capacitor voltage for front A/C fan was 120V on low, and 176V on high speed. The rear A/C capacitor was 120V low, and 280V high. What a difference on the high speed. - the front A/C unit is pulling 4 more amps than the rear with fan speed high and compressor running. I think it is safe to say that the low air flow is causing the front unit to run hot. Probably shutdown yesterday on high temp. Bad capacitor causing the fan to run slow, or bad fan motor, or both? Thank you in advance for any insight.

@olywrestle yes it measures the coolant temp. But it is secondary and as @Duffer51 mentions he has a light on the dash as well. But for my Windsor there is no light, only an alarm. And it was a bad temp sensor. That may be why you get an alarm when gauges show good.

@olywrestle I had an additional temp sensor that Monaco installed by the exhaust manifold that did not go to the gauges but does cause an alarm. Found that this temp sensor was bad. Here is a pic of it. Not sure if you have the same thing, but this is Monaco installed. Is not used for gauges or ECM input on my coach. Many who have this set up have had the wires disconnected on theirs. Probably because it was alarming because of a bad sensor.

Jeff - so did you eliminate the muffler? If so, any noticeable difference in performance or noise?

Continuing this thread with a few questions. I have made the latch adjustment to the entry door to where it does not have near the travel to open as it did before. Reading and watching videos I also discovered that the door has two latching positions. When I tested my door it seemed to only engage the first latching position. I have made adjustments to the striker bolts and can get the door to latch to the second position, but only by pushing on the door fairly firmly. It will easily go into the first latching position, and then require a shove to get into the second. I have read through this thread and also downloaded and read the files and found out that the striker bolt needs to have some up and down movement. Needs to float. My striker bolts are very hard to move even when they are loosened. Looking behind the plates the caged nut seems to be rusted causing it to not move at all. Here are a few questions I have. 1) How much up and down movement should they have after being tightened and how easy. 2) Can I remove the striker bolt completely without the caged nut falling down in the frame? I am looking for a way to clean the rust off and getting it loose again. Other thoughts or suggestions.

To answer your question @Happycarz, I have done this. The SD controller for my coach was the five wire set up. Three wires going to the SD controller (ECM, 12V, Neutral), and two wires going from the SD Controller to the pintle valve (SD output, neutral). When the fan started to run WAO all the time and I determined the SD controller was bad, I began to research options and went with an option I found on IRV2, see attached white paper. For the five wire set up, there needs to be a PWM motor controller that will step down the voltage to the pintle valve such that you are able to set the RPM's at cold start-up. If not, the fan will barely spin as the cold start up voltages from the ECM are too high to spin the fan much. I have the voltage coming out of the motor controller going to the pintle valve set to spin the fan around 600 RPM for cold start up idle. The white paper uses the 12V hot wire as the control signal to the motor controller, but I did enough research and testing to convince myself, and to your point, that I could use the ECM voltage instead of the constant 12V. I have been running my coach this way for nearly 2 years, thousands of miles, through Colorado, over Monarch Pass, other difficult terrain, and I cannot see any distinguishable performance in in engine cooling versus the OEM setup. An interesting event happened about a month ago when the fan started to ramp up to WAO and then back to normal RPM. When I tested the ECM voltage to the pintle it was erratic at times. A few days later I noticed that my Air Intake Temperature sensor was erratic and would stay at high temps of 185F plus. I knew this to be a false indication as it would show 185F on a cold startup. The light went off for me that maybe this was causing the erratic ECM input to the pintle valve. I installed a new Air Intake Sensor and wouldn't you know, everything is back as it was. The hidden blessing for me is I always wondered how much the ECM really affected the pintle valve, and if it included the Air Intake Temp sensor as an determinate factor. Well I have my answer. Not only does the ECM have an immediate affect on the fan speed, it also takes into account the Air Intake Temp sensor along with the Coolant Temp. I investigated this route in the first place because the cost to replace the SD module was extremely high in comparison to this fix. I know it is not OEM, but it works as one would expect. The fix is also less than $100. $15 for the motor controller and $80 for the 205F thermal switch. Hope this answers your question. Hydraulic Fan Drive Controller Repair Option.pdf

My research on Thermo Wax Valves for our coaches is that they do not begin to open until around a calibration temp of 190F-200F. And are wide open at +10F which puts the fan operation at WAO. The thermo wax valve operation does not adjust fan RPM based on coolant temperature until those calibration temps. The Sauer Danfoss controllers are PWM PID controllers with variable and switch inputs. They are advanced controllers that take into account coolant and air intake temps and possibly other inputs. Also Dash AC compressor input and perhaps other switch inputs. The system I am using is replicating very closely the thermo wax valve operation. If someone is looking to replace the SD Controller with a Thermo Wax Valve, this option very similarly replicates what the thermo wax valve will do. If my motor controller goes out, I am out $15 for a new one. I believe a thermo wax valve is around $300 plus. The OEM replacement approach was one I considered, but the prices I saw led me to this much lower cost operation that performs very well based on many miles of operation. Maybe @Jdw12345 can share how much his new SD controller was. Plenty of options for ALL to ponder. SOOOO much better than WAO all the time.

The fan speed WILL change (not fixed) as the RPM of the engine changes. I have used a tachometer on my fan at higher engine RPM's. For example, Engine @ idle - Fan @ 850 RPM, Engine @ 1200 RPM - Fan @ 1400 RPM, Engine at 1400 RPM - Fan @ 1650 RPM. As the RPM of the engine goes up, the hydraulic pump RPM increases and in turn increases the hydraulic flow & pressure and in turn the speed of the fan. This is why in Texas and it is 105F outside, the engine temp still stays around 190F and not WAO. Another advantage is you can adjust the fan speed for any climate temps you are in. By just adjusting the motor controller output voltage you can set your fan speed for very cold climates or burning hot climates. Hope this helps providing a better explanation. If you read the irv2 post, there are many coaches running this set up. Costs about $100 and no retrofit to the coolant piping. Just another option to consider.

@Lionel blain I took a similar approach as you initially were thinking. I am attaching a link from irv2.com that I employed. Also attached is a white paper on it. Basically you replace the Sauer Danfoss PWM with a Motor Controller PWM and use a thermal switch as a safety WAO if the engine temps get too high. The motor controller is stepping down the voltage to the control valve to run at a set pressure that will vary as the engine RPM varies for proportional control. I have mine set to 9V that keeps the engine around 190F for fairly flat terrain. You would have to vary for you engine to find that sweet spot and engine temps you want to run at. I do not run my dash AC when first starting the engine at idle. Once on the road I will turn the dash AC on. I also ran wires to the RRB where I mounted the motor controller. I have been using this for over 2 years. Let me know if you have any questions. https://www.irv2.com/forums/f258/sauer-danfoss-fan-controller-option-500058.html Hydraulic Fan Drive Controller Repair Option.pdf

Does anyone use a Battery Monitoring System that can work remotely via WiFi? I would like to be able to monitor while coach is in storage miles from me. Does it even exist?

Kurt, my bad. Evelyn Wood speed reading didn't serve me well this time.

@Idoc57 Just replaced a month ago the T-stat on my 8KW HDKAK. Very simple, just remove the top bolts, and replace. I have a slide out generator so it was a cinch. I don't recall anything about a 3rd bolt. Once you get up there and look it will be obvious.

@wek1958 That is a good point. The T-Mobile box also supports 2.4G. I definitely see a stronger signal to the T-Mobile Box when using the weBoost. I will use the weBoost for my T-Mobile Cell phones as well. I may not be able to explain why, but it works. Also, I have the Drive X RV weBoost which weBoost tech says is the best signal booster for T-mobile for parked and in motion. Again, not smart enough in this field to disprove, but it works really good for my cell phones and T-Mobile Box.

A local glass shop may be able to cut a new lens for you. Hopefully they have the same frosted type. Just take the lens in your picture as a template.

@wek1958 I am using the T-Mobile Home Internet 5G. So far I have had good results. It also works in motion too. I have used it now for several trips. Even one to Big Bend in Texas, not much signal strength. Using my WeBoost right up against the T-Mobile Receiver and then tethered to the repeater/router. No problems for talk/text and streaming. While my rig is in storage, I leave the network on and can access remotely all the wireless systems. I signed up right when they started for $25/mo.

@TDaleABQ Are you disconnecting from shore power when you start your engine? If not, this may be causing your alarm. I have a different rig, but that is what happens when I start the engine and leave on shore power.

@BradHend Here is a video that was extremely helpful for me to get the exhaust manifold bolts out when I had to replace the gaskets. The bolts were extremely difficult, but with patience and using the technique in this video, they ALL came out without ANY of the bolts breaking off. It is kind of long, but bear with it. All the best.

@Notn2bars maybe you just tripped a breaker or GFCI when you nicked the wire. If your refrig outlet is on a GFCI, now may be a good time to change that. The outlet to our coach residential frig was on a GFCI circuit that also supplied power to other outlets in the kitchen. So I had to run a dedicated line to the refrigerator from the GFCI Line input. It would have been so much easier to have done this before the refrigerator was installed. Your project is looking good.

@Pudgy Camper you are doing all the correct tests, also in addition to testing the pneumatic actuator, also test the electronic pneumatic controller that sends the air signal to the pneumatic actuator. @J & Di Cooper describes he had a seal problem in this unit. Cummins Quickserve gives very good procedures for testing these. I also suspect you have a VGT turbo and not a wastegate based on your picture and description. Quickserve will confirm this as well.

I found this post very helpful.