I see 4 areas of concern when it comes to fixing or upgrading a AC:
* Cooling
* Noise
* Preventative Maintenance (Visual and capacitor checks.)
* Tuning (Poor Man's Hard Start Kit up to EasyStart installation)
We have covered all of these, but I still am not sure what to make of the Overload Device #1450-0081 that sits on top of the compressor?
* We don't know what wattage this device is rated at or what the off the shelf part number is?
* Where to buy it? Cost?
And when I review my 6535-671 part list I see there is a part called a "Coil Solenoid" (Part #1460-0081) I do not know anything about.
* What is it? What does it do? Where is it located?
* Is it recommended we replace this Coil Solenoid at that same time you replace the Overload Device, or are the coil windings in this "1460-0081" robust enough to last forever?
* The part numbers are so close... Coincidence or not?
In this video below we can see how an Overload Device works, but I can't find anything about a "Coil Solenoid". Is this some sort of Start Device? (In my schematic this part #20.)
* How much are these parts and where do you buy them.
Note: When I call AirXcel to buy parts I cannot get through, and they are not answering emails I send thru their website. So what to do?
Fast forward to 5:10 to watch the part on the Overload Device:
IMNPRSD -
" I covered the duct and Flex Seal with Butyl METAL Tape... which you can only buy a Walmart of all places. (Not HD or Lowe's.) It's made by DUCK and it use to be $6/roll. Now it's $9/roll I think and you need 2 rolls."
I was looking for the tape you mention rather than using what I have on hand . Would it be either of these 2 choices , as its all I saw in a Super WM
Here is a picture of insulation in my 6537 unit . Am I to understand your model does not ?
Today , I tested and closed up the unit . It sure sounds quiet . All thats left is to re install the unit .
JourneyCat: I don't recommend HVAC tape or duct tape. The butyl coating is great for insulation of the exterior duct and then I sprayed a coating of black Flex Seal over the tape.
The exterior duct I am talking about is the 90-degree bend out of the AC... that you can reach from inside your engine compartment if you have a side radiator.
My coach came with a thin layer of insulation, but it was not in good shape. I can also conclude it's not nearly enough insulation since my interior air temperature out of the roof vents was colder after I butyl taped the 90-degress bend and about 2-3 more feet of duct work behind the rear cap.
* I did find some HVAC with butyl at Home Depot last week so I stand corrected. Apparently you can buy the butyl tape at HD. It's in the plumbing section.
I cannot comment on the insulation inside my AC box because I have never taken it apart.
I see no reason to insulate the hot side of the box, but if you can create an Igloo cooler out of the cold side that makes sense to me. (In theory.)
...And wrapping the blower cage with butyl tape may help to reduce vibration and noise. (In theory.)
When the day comes that I have to overhaul my AC (maybe this summer) I will attempt these modifications using butyl mat and tape.
If you decide to insulate inside your box, please let us know how it goes and if you benefit by more cold air inside your RV?
Similar to the picture you posted .it Looks like mine .I cant imagine adding more to that . ! Although mine is in great condition . with no leaks in the upper area .
On top of that , a couple years back . I had some work done on the rear cap at Lazydays and removed it .
They saw a few flaws in the duct work . So they took an additional 2K from my insurance co . And sprayed the up right duct with expandable foam up to the top Y . Ill not go back to them ever again !
Also I have no concerns about the cooling in my coach . Its actually to cold in there even in the high AZ temps ,
I installed my unit today . All i have to do is connect the 90 elbow up and I'm done .
Then ill test the bedroom sound while its running to see if there is a noticable improvement in the sound . Which I believe , there will be !
I must have mis understood what you meant and was searching for a type of tape . Can you post a pic of the Butyl coating for me that you used ? When I do a search for it . I come up with Flex Seal and a few other items . That being said , I'm not sure what you used .
JourneyCat: Can you let us know where your sourced your compressor "overload device"? I could not find out the Wattage rating to know where to order one?
Did you replace your compressor "coil solenoid" or reuse your old one?
My unit is installed and running much more quiet !
Although , I did not change either of those items ..
I hope those items dont come back and bite me .
JourneyCat: I don't think it is that important. Both are safety only switches which means they are normally closed all the time and would only open if your compressor overheats.
Plus they are PTCR type devices, which should mean the bi-metal material in the PTCR is good for hundreds of cycles... just like your Start Up Capacitor PTCR which gets cycled "On" and then "Off" every time you start your AC.
Anyway, I started this thread after reading the thread you started, where you talked a lot about overhauling your 6537 Colman Mach (2-Ton) AC, so I hope you return to that thread and give us a summary.
For example, can you summarize your Basement Overhaul parts costs and include links or company phone number on where to buy all these parts? This will greatly help the rest of us plan for the day we pull our basement AC for repair... and at that point it sounds like a full overhaul is advised if you have 10+ years of service.
Here's the link to JourneyCat's 6537-Basement AC Overhaul thread for everyone benefit:
More questions I will go to your website to get answers:
Do you think the noise reduction was due to the plastic blower cages you replaced?
...And if you added insulation, and/or butyl tape, did that help reduce vibration noise?
...Did you keep your stock Start Capacitor Values too? This is the 88-108uF with Motor Starter WSX7. ...Or did you bump-up your Start Capacitor a notch and order a 135-162uF and keep your Motor Starter WSX7 (PTCR) thermal switch?
Poor Man's Hard Start Kit
* 2 Start Capacitors on Amazon for $21.17: TEMCo 135-162 uf/MFD 330 VAC Volts Round Start Capacitor 50/60 Hz
Note: The WSX7 in some ways is a more critical part, because it is subject to failure if you are operating your Basement AC in RV parks with low voltage.
WHAT ABOUT REPLACING THE WSX7 MOTOR STARTER WITH AN ADJUSTIBLE 5-2-1 Relay?
Now that we understand the purpose of the start capacitor, and why it may make sense to notch-up the capacitance one notch, what about optimizing your AC start circuit further by replacing the WSX7 Motor Starter (PTCR) with an Adjustable Supco APR5 (5-2-1 relay)?
Those of you following this thread may want to hop over to this new thread I started on installing a Supco APR5 (Adjustable 5-2-1 Relay) with a larger start capacitor:
Note: I want to emphasize this is all theory. I do not pick up my RV from storage until April/May 2021 so I have not field tested any of these assumptions. However, I have ever reason to look forward to making these upgrades unless someone steps on the brakes! ...And I would thank you for doing that if you are an RV AC expert and know I'm breaking the rules. Otherwise, maybe my suggestions are rooted in logic and will prove to be a valuable upgrade for very little additional cost. (TBD)
Update: I started looking at this 5-2-1 solution to improve on the OEM hard start kit. The idea was to create a more robust circuit that would allow your basement AC to start faster and fix the re-starting problems people were having when operating the basement AC when outside temperatures exceed 105F.
Note: The OEM hard start kit includes a WSX7 Motor Start device, which is just a PTC-R that is Normally Closed (NC) and then opens split seconds after the basement AC compressor starts.
So my idea was to use the 5-2-1 relay to replace this PTC-R, but now I think its much easier to just go with an electronic relay switch... made by Supco, called the SPP4E. Moreover, the SPP4E it is a lot easier to install, and cheaper, and it comes with the right sized capacitor that matches the OEM start capacitor value of 88-108uF.
And because the SPP4E is 120V compliant electronic switch, it will not be affected by hot ambient temperatures above 105F. And the SPP4E will be a good back-up device basement AC may want to consider when you can't find parts to replace your OEM Hard Start Kit.
What I don't know is if the SPP4E will operate BETTER then the WSX7 Motor Starter (PTC-R) when you plug into low voltage. I do know, and you can see for yourself in the bottom picture, what happens to a WSX7 when you plug into low voltage... it melts!
Everything went as expected with the exception of these questions:
* I'm having trouble understand why the Neutral Wire only measures ~11A... when L1 settles down to ~9A and L2 settles down to ~11A. What I'm I doing wrong? I was expecting 0-3A as I under the impression the current difference between L1-to-L2 would be what is returned on the neutral. So, I could use a little help explaining the neutral wire measurement.
=== Backgound Measurements ===
==> When on shore power, not generator power, is measuring the current in the neutral return line meaningful?
* When I start the basement AC, firt the blower in the basement AC comes on and I get ~4A on L1 first; and then it shoots up to ~47.7A of "in-rush" before it settles down to 14A and then reaches a steady operating current of ~11A. This is all normal even though the Colman Spec says one compressor running will require 14A.
==> And a few moments later the #2 Basement AC Compressor starts... the "in-rush" jumps to 44.7A... then it settles down around 11, like it should.
* Why is compressor #2 current (L2) higher than Compressor #1 (L1) when both basement compressors are running?
* Why is compressor #2 current (L2) higher than Compressor #1 (L1) when both basement compressors are running?
I'm no expert but all mechanical devices age, and age differently, so I'm not surprised that the current draw is different in two, seventeen year old compressors.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
That sounds like a good answer, but I would think as bearings wear and motor windings heat-up and create more resistance over time... I would think an aging motor would use more amps of current over time? Does it?
And maybe the Coleman-Mach spec is just a reference measurement. I.e., maybe all Basement ACs will be within a certain range.
For now, at least I have some reference numbers to keep; and so long as I use the same muiti-meter when the day comes my basement AC needs some service, maybe the difference in my measurements today vs. in the future will help me isolate a weak compressor or relay or PTC-R.
The most important parts to this field test are:
* Why is L1 current (on Circuit #1, which includes 4 amps for the blower motor) more than the L2 current for the #2 Circuit (which only includes just the #2 compressor)?
* And, when on shore power, not generator power, is measuring the current in the neutral return line meaningful? And if so, how do you interpret it?
* And when on generator power, which I'm more concerned about, will I expect to see a "summing" of the currents in L1 + L2 reaching between 24A-29A (with my residential refrigerator running) which is what I do see on my power panel, or is there another explanation?
==> LRA stands for Locked Rotor Amps, and this is the maximum current your compressor should be subjected to. Therefore, if you see an "in-rush" current that exceeds the LRA of 54.0A you really need to stop using your Basement AC and find out why this is the case?
* Also, not all, in fact most, multi-meters do NOT measure "in-rush" current. And in the past these instruments were very expensive. Now you can get one on Amazon for $69 with all you other multi-meter functions, so if you are looking for a high quality multi-meter with a "clamp" check out Amazon.
I suspect that, most certainly, there's a tolerance range and the two compressors might age differently. You could always contact the current vendor and ask if your readings are a problem or not: https://www.airxcel.com/rv/coleman-mach
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
* Why is L1 current (on Circuit #1, which includes 4 amps for the blower motor) more than (wrong... I meant to say LESS THAN) the L2 current for the #2 Circuit (which only includes just the #2 compressor)?
To say it another way...
The spec says Circuit #1 is supposed to be higher than Circuit #2 amp draw... and it is until the #2 compressor starts. Then the amp draw on L2 is higher than L1 in the main circuit panel. Why is that?