Dave H M
IL
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Joined: 08/11/2006
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jav may have a point - the separator between the plenums or air control partition in mine was a terrible install.
Also I was gonna mention that my freeze sensor was dangling in the compartment, but apparently that cannot be your case.
good luck
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dougrainer
Carrolton, Texas
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Joined: 06/11/2007
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Krause wrote:Let me run this by you guys- I haven't looked at it but has anyone ever modified their A/C so that it is controlled by a proper thermostat? When I look at mine I don't think it can be done but I find it annoying that it NEVER shuts off. You can set the temp with one dial and set the fan to "Low" or "high" on the ceiling unit. If you set it to high, it really blows and can be very uncomfortable. Seems to me if you could cycle the unit it would avoid some of these problems.
Having said all of that I will get it serviced in the spring.
You have mechanical controls--NO freeze sensor. You do have a Tstat (mechanical). Have you tried turning the tstat down a little or do you have the tstat on full cold? It is possible that you have a defective Tstat. On your system, you need to make sure the tstat sensor tube is in the correct place. You also need to make sure that the exhaust and intake is adequately sealed to prevent leakage. Your type model, it is common to have freeze ups on Low Fan/Cool. You can modify the system to include a Freeze control and a ceiling or wall tstat, but would probably cost $200 to $300 for the parts. Doug
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mikestock
Vestavia Hills, AL, USA
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Joined: 12/01/2002
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Krause wrote:Let me run this by you guys- I haven't looked at it but has anyone ever modified their A/C so that it is controlled by a proper thermostat? When I look at mine I don't think it can be done but I find it annoying that it NEVER shuts off. You can set the temp with one dial and set the fan to "Low" or "high" on the ceiling unit. If you set it to high, it really blows and can be very uncomfortable. Seems to me if you could cycle the unit it would avoid some of these problems.
Having said all of that I will get it serviced in the spring.
Had a problem with the Dometic 15k unit in my old fifth wheel. It froze up at night. I replaced the freeze sensor with an adjustable timer that cycled the the unit off and on and prevented freeze up. In the daytime I turned the timer off and let it run full time.
2005 F250 Crew Cab LWB Power Stroke, 2007 Montana 3500RL Fifth Wheel,Honda EU3000IS, Honda EU2000i, Porta Bote with 6HP Nissan and sail kit, S&W security system
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nelson
Clio,Mi USA
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Joined: 07/01/2002
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Take the cover and filter off. You soul be able to see the temp censor. It should be located in the cooling fins not hanging free. I had the same issue and compared my other AC to the one that was freezing up and the one freezing up the censor was hanging free unlike the one that was working as it should so I put the censon in the same location as the correct working AC and have not had a problem since. Hope this is your problem as it is a free fix.
2002 Damon Challenger 348 Ford V10
Blue Ox Auto Stop and Aventa II Tow Bar
2001 Ford Sport Trac with Remco Driveshaft Disconnect
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wa8yxm
Wherever I happen to park
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There are two schools and odds are they are both correct. There is also a 3rd issue on SOME models
I have never seen a case of freeze-up that was not due to low-coolant charge. NEVER, and I've seen several cases of it.. That said I'm not a pro. I see others have told you what to do if this is the case
Second school is reduced air flow.. I see you checked the filters but running the fan on HIGH (NOT automatic) has several advantages.. One it warms and dries the evaporator off when it's not cooling, and 2: It masks other sounds (your mind quickly blocks the sound of the blower) And it may prevent freez-up, (I do not know) Also if it is a ducted unit make sure the ducts are clear and not collapsed
The THIRD issue, some models have a "Frost Sensor" this is a metal bulb on a tube usually in a yellow plastic clip that is supposed to be stuck into the evaporator.. In many cases it may have fallen out or not been properly positioned to start with.. CHECK THE SERVICE MANUAL FOR YOUR UNIT before straining your eyes to see if this is the case.
Nothin adds excitment like something that is none of your business
Kenwood TS-2000 housed in a 2005 Damon Intruder 377
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dougrainer
Carrolton, Texas
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nelson wrote:Take the cover and filter off. You soul be able to see the temp censor. It should be located in the cooling fins not hanging free. I had the same issue and compared my other AC to the one that was freezing up and the one freezing up the censor was hanging free unlike the one that was working as it should so I put the censon in the same location as the correct working AC and have not had a problem since. Hope this is your problem as it is a free fix.
What you saw was the Freeze sensor. NO Temp sensor is installed in the evaporator fins. The OP has NO freeze sensor. Just a Mechanical Tstat with the standard copper probe sensor. Doug
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dougrainer
Carrolton, Texas
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wa8yxm wrote:There are two schools and odds are they are both correct. There is also a 3rd issue on SOME models
I have never seen a case of freeze-up that was not due to low-coolant charge. NEVER, and I've seen several cases of it.. That said I'm not a pro. I see others have told you what to do if this is the case
Second school is reduced air flow.. I see you checked the filters but running the fan on HIGH (NOT automatic) has several advantages.. One it warms and dries the evaporator off when it's not cooling, and 2: It masks other sounds (your mind quickly blocks the sound of the blower) And it may prevent freez-up, (I do not know) Also if it is a ducted unit make sure the ducts are clear and not collapsed
The THIRD issue, some models have a "Frost Sensor" this is a metal bulb on a tube usually in a yellow plastic clip that is supposed to be stuck into the evaporator.. In many cases it may have fallen out or not been properly positioned to start with.. CHECK THE SERVICE MANUAL FOR YOUR UNIT before straining your eyes to see if this is the case.
In your every case of low coolant. HOW did you verify that it was a low charge? Doug
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javaseuf
California's Gold Coast
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Joined: 03/30/2005
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nelson wrote:Take the cover and filter off. You soul be able to see the temp censor. It should be located in the cooling fins not hanging free. I had the same issue and compared my other AC to the one that was freezing up and the one freezing up the censor was hanging free unlike the one that was working as it should so I put the censon in the same location as the correct working AC and have not had a problem since. Hope this is your problem as it is a free fix.
This doesn't apply as we have already established that the OP's unit doesn't have a freeze sensor.
And, just in case the OP is confused with the term "temp sensor", there will be a capillary tube that comes off of the mechanical thermostst and this MUST NOT make contact with any part of the coil or any metal. It should be contained in a rubber "O"-ring on a bracket that insulates the bulb from touching metal.
If this cap tube would touch metal, it would cause the compressor to short-cycle since it would then be sensing the temperature of the cool metal and not the return air temperature.
* This post was
edited 11/05/09 02:08pm by javaseuf *
Steve
2007 Springdale 291RKL
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"Nobody knows how we got to the top of the hill, but since we're on our way down, we might as well enjoy the ride". ("The Secret Of Life", James Taylor).
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javaseuf
California's Gold Coast
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Joined: 03/30/2005
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javaseuf wrote:nelson wrote:Take the cover and filter off. You soul be able to see the temp censor. It should be located in the cooling fins not hanging free. I had the same issue and compared my other AC to the one that was freezing up and the one freezing up the censor was hanging free unlike the one that was working as it should so I put the censon in the same location as the correct working AC and have not had a problem since. Hope this is your problem as it is a free fix.
This doesn't apply as we have already established that the OP's unit doesn't have a freeze sensor.
And, just in case the OP is confused with the term "temp sensor", there will be a capillary tube that comes off of the mechanical thermostst and this MUST NOT make contact with any part of the coil or any metal. It should be contained in a rubber "O"-ring on a bracket that insulates the bulb from touching metal.
If this cap tube would touch metal, it would cause the compressor to short-cycle since it would then be sensing the temperature of the cool metal and not the return air temperature.
And BTW, in my years of servicing, I can count on one hand the number of units that froze-up because of low refrigerant. The most common cause is dirty fins on the coil.
* This post was
edited 11/05/09 02:07pm by javaseuf *
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dougrainer
Carrolton, Texas
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javaseuf wrote:javaseuf wrote:nelson wrote:Take the cover and filter off. You soul be able to see the temp censor. It should be located in the cooling fins not hanging free. I had the same issue and compared my other AC to the one that was freezing up and the one freezing up the censor was hanging free unlike the one that was working as it should so I put the censon in the same location as the correct working AC and have not had a problem since. Hope this is your problem as it is a free fix.
This doesn't apply as we have already established that the OP's unit doesn't have a freeze sensor.
And, just in case the OP is confused with the term "temp sensor", there will be a capillary tube that comes off of the mechanical thermostst and this MUST NOT make contact with any part of the coil or ant metal. It should be contained in a rubber "O"-ring on a bracket that insulates the bulb from touching metal.
If this cap tube would touch metal, it would cause the compressor to short-cycle since it would then be sensing the temperature of the cool metal and not the return air temperature.
And BTW, in my years of servicing, I can count on one hand the number of units that froze-up because of low refrigerant. The most common cause is dirty fins on the coil.
You read my mind on this post. I have 31 years of RV AC service and I can count on 1 hand the number that had freeze ups due to low charge. Doug
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