Gary Cole

Tom when I get back into town I'll take a look at my notes. I can say that removing the ceiling panels isn't as difficult as some would imply. I removed all of my front ceiling panels in the course of replacing a faulted romex cable which fed  my front AC. I discovered that the fiberglass insulation was poorly installed, even missing in some places, and decided to replace all with foamboard as I had already pulled 3 panels. I'm thinking that I easily doubled my ceiling R- value. I should have taken some before and after temp readings.

A heat pump control board has a backup heat function which is used when the outside temp falls to a certain temperature. That point could be used to control the existing heating system if so desired. Or one could use independent thermostats. I like the redundancy  of independent heating and cooling systems in our RV application. Just me. Again when the ceiling panels are removed one can pull the necessary conductors. Those who have units with a defrost option could spend another $40 for a defrost board if they wanted. Generally not necessary. One would would have to install a small control transformer large enough to handle the board and contactor coil load. $20.00 maybe. The only 4 inputs necessary for the board would be thermostat, fan, ambient temperature, and evaporator coil temperature. The remote sensor would not be used as conditioned space temperature is sensed at the thermostat. I haven't given fan speed much thought at this point. A few different options are available. I would consider variable speed control in order to reduce the annoying blower noise similar to that found in high end modern units. 

I picked a unit at random and found a control board for $176.00. However Ebay has boards for as little as $50 with a warranty. I'm thinking these are might be overstock out of the box new parts. Really don't know.

 This is a project in my mind at this point so I'm sure there are some loose ends still left. Any input would be appreciated.

I would prefer to be prepared with a plan and parts on hand when the inevitable comes. Always at the worst possible time and place it seems someone here observed. 

I noticed a few weeks ago that the compressor start time delay function in my front AC seems to be keeping its own time lately.

As Tom observed this upgrade would not be for everyone. However for those with low hour use units and able to do some or all the work it is an option.

I don't know how the rumor started that these units are not serviceable. For about $150 one can scrap the OEM board if it fails and convert to generic heat pump boards which are used throughout the industry by dozens of manufacturers. These components will always be available and fully supported so you would be free of flaky arbitrary support which is common to niche manufacturers. I would remove a ceiling panel and install a hard wire cable so that I would always have the option of wireless or hardwire control from my choice of $40.00 state of the art thermostat. The most expensive component in the rooftop unit is the compressor which I have seen for less than $200 at times. However they seem to last forever if they are operated at a reasonable voltage and kept at full charge as they depend on refrigerant from the low side suction line for cooling

1 hour ago, Bill R said:

donut type stop leak clamp

Not sure what that is. Might be a weight or rubber material used to control line vibration. If the unit has been running without a charge the system is going to be contaminated. 

Problem doesn't sound speaker ohm related. Using a 4 ohm speaker on a system rated for 8 ohms makes great big sound ,,,for a while anyway.

2 hours ago, Jim McGarvie said:

Installing a fan--or propeller--backward does not reverse the flow. It may make it less efficient, however.

True, a blade with a compound profile will be less efficient 

I installed a 24 point terminal strip, listed for stranded conductors, under the dash with a dedicated 10 ga conductor from the main ground lug located in the FR bay. Most everything now has a separate ground wire. Probably overkill however DC circuits with dedicated grounds which are labeled with their corresponding circuit,fuse number, and  located at a known common grounding terminal make trouble shooting much easier.

I would buy a 3D printer and learn how to use it before I would pay someone $45.00 for a fancy bottle cap. I've avoided one particular European car maker for years due to their rapacious parts pricing. I began to suspect that their cars were engineered to consume parts on a regular schedule.

Rumor has it that something at Walmart or Dollar General,for less than $4, and much prettier, would do the job. My accessory Keurig coffee cup strainer in polished nickel is getting nervous right now. I've also seen some tea bag strainers that would do the job.

Crazy high. A rebuilt 2500 with a 2 year warranty can be had for $2500.00. Spending $18,000.00 to tow it out of that shop would be more satisfying.

4 hours ago, Gary 05 AMB DST said:

Monaco/Holiday Rambler used a generic wiring for their units. They ran wire to everything that could appear in the any motorhome. On my 05 Ambassador, being the lowest model, has coils of wire in many places that weren't needed. If it isn't being used, it isn't needed.

Gary 05 AMB DST

Wire cutters. My favorite tool since I became a Monaco owner

Kevin with your phone if you go into settings/connected devices/+ pair new device you should be able to see the Bluefire bluetooth device  ID and pair with it one level below the Bluefire software. Your phone will then stay connected until you move out of range. I would be surprised if it is less than 20-30 ft. Does not see 1708 or 1939 protocol at that level.

4 hours ago, Yoaks5 said:

disconnects about every 20-30 minutes

I'm wondering what class the Bluefire dongle is? Bluetooth range is from something short of a county mile to 1.5 ft  depending on class. Can you pair with the Bluefire dongle with your phone? If so do you experience the same disconnection problem? If not then I wonder if the software isn't disconnecting because it doesn't like the  bandwidth?

Bluefire is clearly using a generic Bluetooth $3  chip set and not an in house design. So the drop out problem  is puzzling.

2 hours ago, Scotty Hutto said:

Use the Aladdin J1929 bus cable in the side console instead of the transmission cable.

Scotty my 2005 Diplomat does not have a tap for the Aladdin. The end of line J1929 from the engine EMC plugs into a short pigtail at the Allison control module. That is why I'm thinking the end of line resistor must be in the Allison module.  So that is why I was thinking of just hard wiring a tap and 9 pin port to minimize the number of connections, or using pre made as you did ahead of the Allison module. The Bluefire system would not need the J1708 bus so I would only use 3 wires of the 9 pins on the port and 12v -,+

13 minutes ago, Scotty Hutto said:

Bluefire is an option, but be aware the engine diagnostic port on your 2005 Dip is a J1708

True, very frustrating. The diagnostic port at the engine is J1939. Whose idea was that? The J1708 is only 9600 baud. Too slow for practical monitoring.  I'm looking at the possibility of teeing  the J1939 can bus cable at the Allison transmission module in the front run bay. I'm thinking the transmission module has the required internal  terminating resistor. Plug in tapping tees are available  or could be made.  Any opinions from those who know  more about this and if this would work?

1 hour ago, Ivan K said:

I am surprised there isn't any shop around there that would drop bottom controls of the transmission and figured it out if that's where the problem really is.

The solenoid rebuild kit isn't all that expensive. Pretty much any transmission mechanic could do it. I'd probably try it myself. Not much to lose at this point. 

I want a secret wire that I can apply 5 volts to that tells Allison to shut up and quit arguing with me.  You are not low on oil honey. Forget about it. I just checked it for the 3rd time. The jacks are up. What do you know? Quit nagging. Stop worrying about the parking brake. My job. I'm not an idiot. I don't care if you aren't happy with 6th gear sync. Its probably all in your head. If not, my bad. If 3rd gear solenoid is cranky, well try one that showed up for work. We can do without 3rd gear today.  We'll worry about why later. Start turning those gears. I know its hot outside. Honey this is Grapevine Pass. Everyone is hot. Giddy Up. 

Moderator EDIT.  This is NOW a new topic and is here.  Please RESPOND THERE and disregard this one....

After reading many posts of this sort I looked at my schematic some time ago and noticed that there were 2 sensors in addition to the speed sensor  that could shut down or disable. Maybe more, didn't spend too much time looking at. One was a n.o. contact and the other was a resistance sensor. I thought at the time that they could be bypassed quite easily and temporarily with a jumper and a fixed resistor. Many of the problems were wiring or faulty sensor related. Wonder if any of the trans gurus here  have given this method of getting home any serious thought? I really hate being stranded and at the mercy of the closest mechanic. 

1 hour ago, Tom Cherry said:

You SHOULD NOT need to add spacers….do the above….

Tom is right on here. Something has changed and what that was needs to be investigated and corrected and not remedied with a band aid solution.

Lot of information here. Thinking about something as I read this material . Very few diesel locomotives and I suppose other large diesels do not use antifreeze because an eg antifreeze leak that gets into the oil is going to very likely wipe out the bearings. Another reason is that pure water has the highest cooling capability. They keep the water above freezing with a circulating heater when necessary. They do use traditional and inexpensive  corrosion inhibitors and additives to protect the liners from cavitation.  Wonder how much we are told about these products, including oil,  is oftentimes largely the latest and greatest hype from the marketing people with little substance?

Great if it is something that simple. I re-read your post and your observation that the unit shuts down normally, i.e. compressor and evaporator fan together means that the board is receiving a command to shut down. I'm not really familiar with these units other than having to replace a freeze control sensor one time. However I'm thinking after looking at Tom's information that the only 2 inputs which shut the unit down in normal fashion is  the remote sensor which over-rides the primary enable command from the thermostat and the thermostat itself. The ambient temperature sensor is related to heat pump mode.  The freeze sensor shuts the compressor down however keeps the evaporator fan running in order to defrost the coil. This is assuming your board and thermostat are good of course. There are a couple of people on this forum  here who do know a lot about AC and these units. 

If you have a 22 degree temp differential you don't have compressor problems when it is running. Which rules out a low charge or a worn compressor. Could still have a winding problem causing overheat though unlikely with the symptoms you describe. You can jump the contactor from inside bypassing all control circuits but the high temp limit on the compressor to check the condensing unit. 

Like your solution. I spent a considerable amount of time grinding a deep socket down to nearly nothing  when I pulled my sender. Not a perfect solution.  The problem with a standard  deep socket is that the top of the socket tapers and doesn't provide enough clearance with the upper portion on the sender. 

5 hours ago, Ray Davis said:

It's mysterious to me but some folks seem to actually enjoy working on their coach to the extent of reengineering things. 

It could be that RV's provide a "vehicle"  for many different hobbies and interests short of plowing the north 40 with a team of mules. There might even be an Amish version of that RV. Engines, electronics, woodworking, interior decorating. For the thrill seekers air leaks, fading brakes, the smell of smoke from under the dash, my transmission never did that before , predatory mechanics and tow trucks.  I have even seen people carrying what appears to be a flower and vegetable garden and set it up and repack it as they go.  

11 hours ago, Mike H said:

PHd's were lucky if they could get a job at a 7-11 or Eckerds. 

I'm reminded of a joke that made the rounds in Houston in the  mid 70's when my brother in law, with degree in petroleum engineering and laid off from Phillips 66 , went to work part time pumping gas at a Phillips 66 station, (you can't make that up) not to far from his house because he could walk to work.  " What is the difference between a seagull and a petroleum engineer in Houston ? A seagull can make a deposit on a new car".

4 hours ago, Scotty Hutto said:

How much? That’s virtually impossible to quantify, because failure of electric motors is difficult to predict. 

I agree. The high amp start surge is brief. Particularly if the motor starts unloaded which is the case with a refrigeration compressor. The brief heat generated is absorbed and dissipated by the motor's mass in a well designed system and has less of an impact on windings than voltage spikes which occur for a number of reasons.  And hermetic compressors are very well designed as shown by their trouble free long life. Soft starts seem over priced for what you get and the vendors seem to be overselling some benefits. I noticed they don't provide any hard data on certain implied benefits.  One can now buy a VFD for less which has hundreds of fun programable functions including soft start, delay, torque management, current management, power and speed control, digital and analog I/O, the list goes on. My choice without a doubt if I wanted to play around with reduced load starting with the option of load management.  Most drives have more than a 1000 programmable parameters and functions. There is a phenomenon called conductor ringing which produces high voltage spikes at long conductor lengths. The reason for inverter rated motors. Not a problem under 100' or so.

Need to consider minimum rpm necessary for compressor oiling for anyone who might do something like this. 

A VFD will not produce more voltage than supply voltage to the DC bus however it can reduce motor speed using frequency control in the case of low voltage. Something to consider for low voltage park problems?