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RE: Fridge on the fritz!
When the cooling unit cools properly on one heat source gas or electric and not the other, then the cooling unit, with only a few exceptions, is good and the problem lies in the heat source that is not functioning properly.
It seems to work on AC so I would start with cleaning the burner and orifice.
Rob
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Rob's
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08/17/11 07:50pm |
Tech Issues
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RE: 5th Wheel landing gear motor repair
Bevel Gear Kit
STANDARD DUTY 2000 lbs - 75030
HEAVY DUTY 3000 lbs - 75029
DIRECT DRIVE 4000 lbs - 75029
DIRECT DRIVE 5000 lbs - 75029
Bevel gears should always be changed as a set even though 1 gear looks good.
Rob
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Rob's
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08/17/11 10:23am |
Tech Issues
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RE: Norcold N611LT Fridge Problems
Cooling System Monitoring
The controls monitor cooling system performance when a heat source is active. If the controls sense that the system is not cooling, it displays a fault code ("n"/"no" "co") and locks out all heat energy sources.
First "No Cooling" Fault Occurrence
Users can reset the controls by turning the refrigerator off then back on. The user resetting option can only be accomplished when the controls record the first "no cooling" ("n"/"no" "co") fault occurrence. The completion of a full cooling cycle will remove the
recorded first "n"/"no" "co" fault from memory and returns the controls to normal monitoring operation.
Two Recorded "No Cooling" Fault Occurrences
If the controls detect two consecutive recorded "no cooling" faults , the "n"/"no" "co" fault code displays and the controls will lock out all heat sources (AC/LP/DC). The power board can then be reset after troubleshooting and testing cooling system operation.
Rob
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Rob's
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08/15/11 06:30pm |
Tech Issues
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Absorption Refrigeration System
Maximum COP of ideal absorption refrigeration system
In case of a single stage compression refrigeration system operating between constant evaporator and condenser temperatures, the maximum possible COP is given by Carnot COP:
https://blufiles.storage.live.com/y1pH6tORY4sDZI-H0y2d10x2EEiS1O0AKT8yQ4oDkjqyVC8YGsZ7ftS9b0wVzqIVgr7-MJTyjfL8Fw/14.3.bmp?psid=1
If we assume that heat rejection at the absorber and condenser takes place at same external heat sink temperature To, then a vapour absorption refrigeration system operates between three temperature levels, Tg, To and Te. The maximum possible COP of a refrigeration system operating between three temperature levels can be obtained by applying first and second laws of thermodynamics to the system. Figure 1.1 shows the various energy transfers and the corresponding temperatures in an absorption refrigeration system.
https://blufiles.storage.live.com/y1pMc6f8PLa6hF5su1VuaWf9TLn9RnVq5Kc62fTQBucihr5cFg2A0Kqpm5DXnystvc4fbgNS-n2NsE/Fig.%201.1.bmp?psid=1
Figure 1.1: Various energy transfers in a absorption refrigeration system
From first law of thermodynamics,
https://blufiles.storage.live.com/y1pH6tORY4sDZL7oWkTgk1_G6JtimfuY14e_kJbu7YG0TpW3qilztGLOotHOu-aSW8NqlT38rowuUM/14.4.bmp?psid=1
where Qe is the heat transferred to the absorption system at evaporator temperature Te, Qg is the heat transferred to the generator of the absorption system at temperature Tg, Qa+c is the heat transferred from the absorber and condenser of the absorption system at temperature To and Wp is the work input to the solution pump.
From second law of thermodynamics,
https://blufiles.storage.live.com/y1pzARRA-WinFKHA3X0k5HMKMfIHAmWfbSVjJb0qmLauAEpuNFIVHGameDUliOgDzpqUNo4WDMx8qg/14.5.bmp?psid=1
where https://blufiles.storage.live.com/y1pzARRA-WinFJPlBBlSWUQ4CPl4gLV8A5u2sBsrYcbv5zTLcv0Q7c4_LZ-5PnaPkEeXPDwP_99gbM/14.5a.bmp?psid=1 is the total entropy change which is equal to the sum of entropy change of the system https://blufiles.storage.live.com/y1p8TjDxf749-vQxffy5UahoIjmKzAq08tDNF1HdJr6z_BBWjmgqWHrVpwNKJW1ppAl835IxrkWOsQ/14.5b.bmp?psid=1 and entropy change of the surroundings https://blufiles.storage.live.com/y1p8lzfsr-g8Xz3wMmRwaNqDiyYCvk5U-OuyGLRSebpZ5aO3Ye1x8i-Kt5t9eBzdtwrvRnBkJqTodw/14.5c.bmp?psid=1 Since the refrigeration system operates in a closed cycle, the entropy change of the working fluid of the system undergoing the cycle is zero, i.e., https://blufiles.storage.live.com/y1p8TjDxf749-vQxffy5UahoIjmKzAq08tDNF1HdJr6z_BBWjmgqWHrVpwNKJW1ppAl835IxrkWOsQ/14.5b.bmp?psid=1 =0. The entropy change of the surroundings is given by:
https://blufiles.storage.live.com/y1pLZ2sI2C21Yztokh5FHvc_-apBBpw1n7hupvWqjotDKsUYT2x8bJbno82zyOlxlopaiYcCxyUGAs/14.6.bmp?psid=1
Substituting the expression for first law of thermodynamics in the above equation
https://blufiles.storage.live.com/y1pLZ2sI2C21YznrTYVJxc5BFgxwqYu5Wc7Ba3ivXP5_O3Y-tdUNVNIrfJ_xM6GYjMT4_WKEXy_4GA/14.7.bmp?psid=1
Neglecting solution pump work, Wp; the COP of VARS is given by:
https://blufiles.storage.live.com/y1pTBin5Ob0QpdrygbvxkObTHr-Sk9hk2ZfogwYTfRFvPPBr3kCXL9fI1fqX8eijQNGWqIRBgxWif4/14.8.bmp?psid=1
An ideal vapour absorption refrigeration system is totally reversible (i.e., both internally and externally reversible). For a completely reversible system the total entropy change (system+surroundings) is zero according to second law, hence for an ideal VARS .
https://skydrive.live.com/?cid=3dffe62bc189614e&sc=photos&uc=1&id=3DFFE62BC189614E%21180#cid=3DFFE62BC189614E&id=3DFFE62BC189614E%21226&sc=photosHence:
https://blufiles.storage.live.com/y1p2JoDp-Rt4hjd2xDVYlX4Qnhq2jQJ6vCwjJ3lyamttHw1BEE5gPJzw6oc5QYFc25t4VqObu3b5kQ/14.9.bmp?psid=1
Hence combining first and second laws and neglecting pump work, the maximum possible COP of an ideal VARS system is given by:
https://blufiles.storage.live.com/y1pdko-R8WM7YiTjfvhLkwszkTLnp2DN-aeHXUMR-mOnS3Cq8PPi-iCqoSKEzOSi05o2rt1-ktD1Xk/14.10.bmp?psid=1
Thus the ideal COP is only a function of operating temperatures similar to Carnot system. It can be seen from the above expression that the ideal COP of VARS system is equal to the product of efficiency of a Carnot heat engine operating between Tg and T oand COP of a Carnot refrigeration system operating between T oand Te, i.e.,
https://blufiles.storage.live.com/y1pdko-R8WM7Yg-dER95lzcEzILuQlvhprexCkr_EbOyP0xBvoPmkAsNMLiVeVWZIjWHWw4k0x-wgQ/14.11.bmp?psid=1
Thus an ideal vapour absorption refrigeration system can be considered to be a combined system consisting of a Carnot heat engine and a Carnot refrigerator as shown in Fig.1.1. Thus the COP of an ideal VARS increases as generator temperature (Tg) and evaporator temperature (Te) increase and heat rejection temperature (To) decreases. However, the COP of actual VARS will be much less than that of an ideal VARS due to various internal and external irreversibility’s present in actual systems.
https://blufiles.storage.live.com/y1pg95KhkGyA9-Jp8cm9VMZtJYuTKIZls3IvLs1QsMvPXWW1jAc8CHaZ5rxux64N2CgzrKUnKurHTo/Fig.%201.2.bmp?psid=1
Fig. 1.2 Vapour absorption refrigeration system as a combination of a heat engine and a refrigerator.
It’s this author's option that the use of a fan to satisfy 3 distinct heat ranges is marginal at best and as we have seen many posts with poor cooling and the poor results. This should give a better understanding of how to achieve better refrigeration.
(COP) = Coefficient of Performance
(Carnot) = Carnot Heat Engine
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Rob's
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08/14/11 01:49pm |
Tech Issues
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RE: Dometic Fridge Question...
I am assuming you have 2 switches model # would be helpful. The low ambient switch should be on when the temperature gets cooler and the other one is used in higher humidity. I should tell you that most all of the dometic refrigerators made between 1997 and 2004 have a recall kit that should be installed.
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Rob's
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08/13/11 01:29pm |
Tech Issues
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RE: Fridge issues when water heater kicks in
When we turned on the overhead 12 volt lighting inside the RV - the fridge light would come on - and off when we turn the interior lights back off. This is, of course, NOT how the fridge light normally operates.
Given that fact you are experiencing 12V problems with the fridge light I would suspect there is a 12V short somewhere in your RV. If the short is affecting the fridge light it will also affect your circuit boards and ultimately the way your fridge works.
Rob
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Rob's
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08/06/11 03:34pm |
Tech Issues
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RE: Trailer Brake wiring
Trailer Wiring Diagrams
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Rob's
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07/30/11 07:50pm |
Tech Issues
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RE: Trailer Brake wiring
Trailer Hub Brake Magnet Replacement Demonstration
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Rob's
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07/30/11 12:04pm |
Tech Issues
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RE: norcold n811
Check thermistor resistance
Temperature* Resistance*
(F) (ohm )
85---8.1– 9.0
80---9.1–10.0
75---10.1–11.0
70---11.1–12.0
60---12.1–13.0
50---15.5–16.5
40---22.5–23.5
35---24.5–25.5
33---28.5–29.5
32---30.0–32.0
*Approximate Values
Backup Operating System (BOS)
The backup operating system (BOS) is an electronically controlled duty cycle that maintains the refrigerator in operation if the thermistor is disconnected or fails. The BOS maintains cooling by timing the length of time the heat source is energized. When the refrigerator is operating in BOS, the length of the cooling cycle has to be regulated manually using the TEMP switchbutton.
When a colder temperature is desired, changing the temperature setting to a higher number provides additional cooling by lengthening the cooling cycle. For example, if the temperature setting is set to 5, raising the setting to 6 will lengthen the cooling cycle.
When a warmer temperature is desired, changing the temperature setting to a lower number shortens the cooling cycle. For example, if the temperature setting is set to 6, lowering the setting to 5 will shorten the cooling cycle. N61X/N81X Backup Operation. When the N61X/N81X controls shift to BOS operation, the ON LED (green) flashes once every three seconds.
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Rob's
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07/26/11 02:09pm |
Tech Issues
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RE: Norcold N641 No Fuel message
No Fl = Fault Code – Burner failed to ignite or reignite
1. LP gas pressure at the solenoid gas valve pressure tap is 10.5 WC
2. Clean and service burner
3. Check that electrode tip-to burner air gap is correct. Set electrode-to-burner air gap
1/8 to 3/16 inch.
4. Check spark/sense electrode assembly for continuity.
5. Check gas valve solenoid resistance. 79 to 85 OHM
6. Check gas valve solenoid wires for continuity.
7. Check voltage across power board terminals GV and GV GND.
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Rob's
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07/25/11 10:16am |
Tech Issues
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RE: Norcold problem gas only
Try clearing Fault History
No AC Power or Loss of AC Power
If the controls do not sense the presence of AC power or when AC power is lost, the controls:
1. Display the "no" "AC" fault code. (Display Alternating)
2. Sound the audible alarm. The alarm is an intermittent beeping tone. Pressing the mode switch button silences the alarm.
3. Record and store the "no" "AC" fault in diagnostics nonvolatile memory fault history.
AC Power Restored, When AC power is restored, the controls:
1. Automatically restore AC-Manual Mode operation; however, the recorded fault history will not be erased from memory.
2. Silence the alarm and clear then "no" "AC" fault code from the display.
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Rob's
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07/25/11 10:06am |
Tech Issues
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RE: Atwood 2500 problem
Bevel Gear Kit #87108 is usually what goes first inspect or replace. "Tip always replace both gears as a match set even if one looks good"
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Rob's
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07/24/11 08:41pm |
Tech Issues
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RE: College dorm Refrigerator
Dometic makes a good one made in the USA here...
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Rob's
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07/15/11 12:53pm |
Tech Issues
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RE: Kwikee Parts
In October of 2004, Kwikee began shipping steps with an integrated motor/gear box/linkage (IMGL). Steps with the IMGL require a 909510000 Control Unit. Steps shipped prior to October of 2004 may have a variety of motor/control unit configuration. Any steps (except the 42 and 44 Series), regardless of the original motor/control unit combination, can be repaired using the current IMGL/909510000 parts and procedures. If you are needing to repair a 42 or 44 Series, call the Customer Service Department at 1-800-736-9961. Please note, if you are replacing the IMGL on a step that has any control other than a 909510000 Control Unit, you must also change the control unit. Previous Control Units will not work correctly with the IMGL and the 909510000 Control Unit will not work correctly with previous motor/gear gox/linkage configurations.
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Rob's
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07/14/11 03:24pm |
Tech Issues
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RE: dometic rm2611
RM2611
AC
WATTS: 295
VOLTS: 120
OHMS: 48
You should obtain the following readings ± 10%
AC VOLTAGE REQUIREMENTS
Proper Operating Range is 100 to 132 Volts.
If voltage drops below 100 volts, cooling efficiency will decrease with voltage decrease. The refrigerator will not switch to another mode of operation until all AC power is lost.
DC
WATTS: 215
VOLTS: 12
OHMS: .67
You should obtain the following readings ± 10%
DC VOLTAGE REQUIREMENTS
The operational range of the unit is a minimum of 9.6V DC to a maximum of 22V DC, the unit will automatically shut down until voltage has decreased to 18V DC. The refrigerator requires at least 9.6V DC for proper operation; however the panel lights will continue to illuminate until voltage has dropped to 4V DC or below.
Do not use the body or chassis of the RV as a substitute for either of the two conductors. Proper polarity is crucial for refrigerator operation.
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Rob's
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07/09/11 09:40am |
Tech Issues
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RE: Norcold 821N Circuit Board Question
Norcold refrigerator board # 632168001. Latest part # replaces Norcold 621267, 621267001 and 619353
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Rob's
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07/09/11 12:23am |
Tech Issues
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RE: Norcold 821N Circuit Board Question
You should call Norcold about cross reference part#.
1-800-543-1219
N600 and N800 Series Models 1082 Free-Standing LP Model
N841, N821, N641, N621 and 1082 gas/electric 2 door refrigerators, having cooling units with serial numbers from 1038000 to 1099000.
These refrigerators were mostly installed in, but limited to vehicle models 1999 to 2000.
Owners who have had the heater element replaced in one of these cooling units should call: 800-767-9101 to get their refrigerator upgraded to current product configuration.
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Rob's
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07/08/11 03:45pm |
Tech Issues
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RE: Kwikee steps
Its best to use Kwikee OEM parts.
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Rob's
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07/08/11 02:22pm |
Tech Issues
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RE: Norcold 821N Circuit Board Question
These are the part #'s I have for the N62 SERIES - N82 SERIES
Current: as of 2/21/2011
PART# 628674
DESCRIPTION: BASE-POWER BOARD (SERIAL RANGE: N621/N821/N822=9126825 & ABOVE, N623/N823=8970881 & ABOVE)
PART# 618186
DESCRIPTION: BASE-POWER BOARD (SERIAL RANGE: N621/N821/N822=9126824 & BELOW, N623/N823=8970880 & BELOW)
PART# 628661
DESCRIPTION: POWER BOARD (SERIAL RANGE: N621/N821/N822=9126825 & ABOVE, N623/N823=8970881 & ABOVE)
PART# 632168001
DESCRIPTION: KIT-POWER BOARD (SERIAL RANGE: N621/N821/N822=9126824 & BELOW, N623/N823=8970880 & BELOW)
NOTE: IF THE CONTROL ASSY-OPTICAL HAS BEEN REPLACED WITH A KIT-CONTROL ADAPTOR, THE POWER BOARD MUST BE REPLACED WITH A NEW KIT-CONTROL ADAPTER.
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Rob's
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07/08/11 12:10pm |
Tech Issues
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RE: ohms reading for 120 volt fridge element
CURRENT DRAWS - 662, 663, 682, 683, 6062, 6063, 6082,6083, 6162, 6163, 6182, 6183
Automatic Ignition - Less than 500 milliamps or .50 ampsInterior
Light (when equipped) - 300 milliamps (.3 amps)
Humidity Heater - 240 milliamps (.24 amps)
AC Heating Element - 2.7 amps at 110 Volts AC 2.9 amps at 120 Volts
ACDC Heating Element - 13.8 amps at 12 Volts DC16.1 amps at 14 Volts DC
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Rob's
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07/06/11 10:15pm |
Tech Issues
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