starvin marvin Posted August 22, 2012 Share Posted August 22, 2012 Not sure if I have a problem, but stick with me and I'll explain. The van is usually parked on the drive without EHU. When we get ready to go away I plug in the EHU to cool the fridge, which has been left switched off with the door ajar and the gas is turned off. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. The fridge is then switched on and immediately all the correct lights are on and the "clicking" stops and the fridge is cooling again. The fridge was last serviced 12 mths ago. The fridge was removed from the van and the burners/jets replaced, and the flue cleaned etc. This was done as I saw the work being carried out. I don't have a manual for the fridge. There is only one external vent at high level where you can feel the heat coming out. The low level vent if either behind the bumper or I guess under the floor. Clearly the fridge works on mains, as it cools prior to filling it up, and it works on gas 'cause we free camp a lot, and was working on gas 2 wks ago after a similar initial performance. The ques(s) I have is the fridge operating correctly? Right now I don't know if the fridge is working on 230v or gas but its working on something; and I'd like to be a bit more clued up, if possible before I take the van to Mr Fixit. Indeed do I need to do anything? Many thanks Link to comment Share on other sites More sharing options...
Mel B Posted August 22, 2012 Share Posted August 22, 2012 starvin marvin - 2012-08-22 7:57 PM The van is usually parked on the drive without EHU. When we get ready to go away I plug in the EHU to cool the fridge, which has been left switched off with the door ajar and the gas is turned off. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. The fridge is then switched on and immediately all the correct lights are on and the "clicking" stops and the fridge is cooling again. After turning the fridge to 'auto' mode and just prior to loading it do you disconnect the mains and move the van at all? If so, it would normally mean that the fridge would change over to 12v whilst the engine was running, then as soon as you stopped and turned off the ignition it would stop working as they have a safety 'cut-out' which prevents them from working on gas for around 15-20 minutes so that if you've gone to a petrol station it doesn't ignite the gas whilst you're filling up! It could then be that you are loading it up with food etc at around the time when the fridge automatically starts up again - as the mains has been disconnected, and the engine isn't running, it would then go to the only power source remaining - ie gas. Link to comment Share on other sites More sharing options...
onecal Posted August 23, 2012 Share Posted August 23, 2012 Hi,Give us the model No please,,,,the fridge should not look for gas if you are still connected to the mains and by just opening the fridge door. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. It should remain working off the mains only,Why would ,or indeed should it turn itself off when loading ,or by opening the door?Regards,Brendan Link to comment Share on other sites More sharing options...
starvin marvin Posted August 23, 2012 Author Share Posted August 23, 2012 onecal - 2012-08-23 12:24 AMHi,Give us the model No please,,,,the fridge should not look for gas if you are still connected to the mains and by just opening the fridge door.The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas.It should remain working off the mains only,Why would ,or indeed should it turn itself off when loading ,or by opening the door?Regards,BrendanExactly my question. Thanks for that. Link to comment Share on other sites More sharing options...
starvin marvin Posted August 23, 2012 Author Share Posted August 23, 2012 onecal - 2012-08-23 12:24 AMHi,Give us the model No please,,,,the fridge should not look for gas if you are still connected to the mains and by just opening the fridge door.The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas.It should remain working off the mains only,Why would ,or indeed should it turn itself off when loading ,or by opening the door?Regards,BrendanExactly my question, I'll have a look for the model number and get back. Link to comment Share on other sites More sharing options...
derek pringle Posted August 23, 2012 Share Posted August 23, 2012 Mel B - 2012-08-22 11:33 PM starvin marvin - 2012-08-22 7:57 PM The van is usually parked on the drive without EHU. When we get ready to go away I plug in the EHU to cool the fridge, which has been left switched off with the door ajar and the gas is turned off. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. The fridge is then switched on and immediately all the correct lights are on and the "clicking" stops and the fridge is cooling again. After turning the fridge to 'auto' mode and just prior to loading it do you disconnect the mains and move the van at all? If so, it would normally mean that the fridge would change over to 12v whilst the engine was running, then as soon as you stopped and turned off the ignition it would stop working as they have a safety 'cut-out' which prevents them from working on gas for around 15-20 minutes so that if you've gone to a petrol station it doesn't ignite the gas whilst you're filling up! It could then be that you are loading it up with food etc at around the time when the fridge automatically starts up again - as the mains has been disconnected, and the engine isn't running, it would then go to the only power source remaining - ie gas. Hi Mel, Are you talking about driving with the gas switched on?How wpuld the fridge know if you were going for fuel or not--would have thought the 20min. isolation you are talking about is purely a generic safety feature. cheers derek Link to comment Share on other sites More sharing options...
starvin marvin Posted August 23, 2012 Author Share Posted August 23, 2012 Mel B - 2012-08-22 11:33 PM starvin marvin - 2012-08-22 7:57 PM The van is usually parked on the drive without EHU. When we get ready to go away I plug in the EHU to cool the fridge, which has been left switched off with the door ajar and the gas is turned off. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. The fridge is then switched on and immediately all the correct lights are on and the "clicking" stops and the fridge is cooling again. After turning the fridge to 'auto' mode and just prior to loading it do you disconnect the mains and move the van at all? If so, it would normally mean that the fridge would change over to 12v whilst the engine was running, then as soon as you stopped and turned off the ignition it would stop working as they have a safety 'cut-out' which prevents them from working on gas for around 15-20 minutes so that if you've gone to a petrol station it doesn't ignite the gas whilst you're filling up! It could then be that you are loading it up with food etc at around the time when the fridge automatically starts up again - as the mains has been disconnected, and the engine isn't running, it would then go to the only power source remaining - ie gas. Apologies if I wasn't clear. The fridge is not turned to "auto" mode, it is an automatic fridge. I believe AES stands for Automatic Energy Selection. At no time when getting the van ready is the engine started, the ignition is never turned on, nor is the EHU disconnected, or switched off. All we have done on the two occassions we've noticed this happening is turn the fridge off, ie press the on/off button, turn the gas on, light one of the gas rings to ensure gas is there. Then simply press the on/off button again and the correct fridge lights come on and its cooling again. Link to comment Share on other sites More sharing options...
starvin marvin Posted August 23, 2012 Author Share Posted August 23, 2012 starvin marvin - 2012-08-23 8:37 AMonecal - 2012-08-23 12:24 AMHi,Give us the model No please,,,,the fridge should not look for gas if you are still connected to the mains and by just opening the fridge door.The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas.It should remain working off the mains only,Why would ,or indeed should it turn itself off when loading ,or by opening the door?Regards,BrendanExactly my question, I'll have a look for the model number and get back.The model number is RM 6405L, trust this helps. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted August 23, 2012 Share Posted August 23, 2012 starvin marvin - 2012-08-22 7:57 PM ...I don't have a manual for the fridge... You should be able to identify your Dometic fridge's "Model Denomination" from a label inside the fridge. It will start with the letters "RM" (eg. RM123, RM4210, etc.) Having established your fridge's Model Denomination, you should be able to download a manual via this link: http://www.dometicmanuals.com/PROD/MASTERDometic.nsf?Opendatabase For example, inserting RM7605 in the Model Denomination box, selecting EN - ENGLISH as the Language and DOMETIC as the Brand, will produce a list of handbook editions for the fridge/freezer fitted to my Hobby motorhome. (EDIT: I notice that a RM6405L manual is not available as an English-language download. If you put RM6405L in the Model Denomination field and DOMETIC as the brand, but leave the Language field blank, you'll find that the manual is available in 6 other languages, just not English. Not sure how helpful any of those manuals would be to you, though you may be able to glean something useful out of them if you use GOOGLE translate.) Dometic has marketed AES fridges since the 1980s. Earlier models were fully 'automatic' regarding their energy selection, while - from 7-Series appliances onwards - the user had the option of manual selection of the energy source (230V, 12V or gas) or allowing the appliance to make the selection itself. When operating automatically, the priority order of energy selection is 1. 230V AC 2. 12V DC 3. Gas 1. If an AES fridge identifies the presence of a 230V AC energy source (ie. the motorhome is on an EHU), that 's what should be selected. 2. If an AES fridge cannot identify the presence of a 230V AC energy source, but can identify the presence of a 12V DC source (ie. the vehicle is NOT on EHU but it's motor is running), the fridge should operate on 12V DC. 3. If an AES fridge cannot identify the presence of a 230V AC energy source, nor identify the presence of a 12V DC source (ie. the vehicle is NOT on EHU and it's motor is NOT running), the fridge should attempt to operate on gas. It should be apparent from the above (and from Brendan's comments) that, if a motorhome is connected to an adequate 230V AC EHU and an AES fridge is operating using that 230V energy source, the fridge should continue to operate on 230V indefinitely unless the 230V supply is interrupted. An AES fridge in 'auto mode' should only attempt to switch to gas operation if no 230V AC supply, or no 12V DC supply, can be identified. As Brendan has said, opening the fridge door should have no impact on the energy selection process - door shut or door open, if the fridge is running happily on 230V AC it should normally stay running on 230V AC and not look for an alternative energy source. I note from the Dometic manual for my own fridge/freezer that there is a caveat relating to AES appliances and 230V AC operation. This warns of the possibility of an AES appliance attempting to switch to gas operation despite there being a 230V AC connection. This will only occur if the mains AC supply is below (or falls below) 200V. I guess this might happen on a campsite, but I would not anticipate it being relevant in your case. You've said that the fridge was serviced 12 months ago, but you've provided no details of your motorhome or how long you've owned it (and I'm not going to trawl through nearly 700 threads to try to find out!) When it comes to trying to diagnose a (potential) problem, one of the most important pieces of information (that's regularly omitted) is whether a 'change' has taken place. If your fridge used to act differently (ie. did not try to switch from 230V AC to gas), then that would be important to know, particularly if a change in the way it operated were coincidental with the service work that was carried out. Clearly, if you've only owned your motorhome for about a year, you may not be able to say if such a change has occurred. But, if you've owned the vehicle for significantly longer than that, I'd expect you to know if the fridge is now acting differently. As things stand, it appears that your fridge is not operating as it should. Suggest you download the manual for your fridge and see if that helps. Link to comment Share on other sites More sharing options...
Robinhood Posted August 23, 2012 Share Posted August 23, 2012 Derek Uzzell - 2012-08-23 9:17 AM starvin marvin - 2012-08-22 7:57 PM ...I don't have a manual for the fridge... You should be able to identify your Dometic fridge's "Model Denomination" from a label inside the fridge. It will start with the letters "RM" (eg. RM123, RM4210, etc.) Having established your fridge's Model Denomination, you should be able to download a manual via this link: http://www.dometicmanuals.com/PROD/MASTERDometic.nsf?Opendatabase For example, inserting RM7605 in the Model Denomination box, selecting EN - ENGLISH as the Language and DOMETIC as the Brand, will produce a list of handbook editions for the fridge/freezer fitted to my Hobby motorhome. (EDIT: I notice that a RM6405L manual is not available as an English-language download. If you put RM6405L in the Model Denomination field and DOMETIC as the brand, but leave the Language field blank, you'll find that the manual is available in 6 other languages, just not English. Not sure how helpful any of those manuals would be to you, though you may be able to glean something useful out of them if you use GOOGLE translate.) ....for the English Manual, follow Derek's instructions, but search on model number RM6295L. The manual it retrieves under the resulting "English" link is the correct one for your fridge. (and annotated as such on the first page). Link to comment Share on other sites More sharing options...
Derek Uzzell Posted August 23, 2012 Share Posted August 23, 2012 In fact, I hadn't realised how old the RM6405L appliance is. It's an Electrolux-branded model not a Dometic one. If RM6405L is put in the Model Denomination field, EN - ENGLISH selected in the Language field and ELECTROLUX chosen as the Brand, the correct set of manuals will be retrieved. As Robinhood says, the RM6405L manual also applies to the RM6295L model. Link to comment Share on other sites More sharing options...
starvin marvin Posted August 23, 2012 Author Share Posted August 23, 2012 Many thanks, one and all. I'll get back once I've managed to find the time to do the download, and speak to Mr Fixit. Link to comment Share on other sites More sharing options...
onecal Posted August 23, 2012 Share Posted August 23, 2012 Hi, Check your mains supply,and connections ,,,,if the fridge detects under or down to 190V/200V on that model it will look for gas.It should not otherwise when connected to a healthy uninterrupted mains supply. Also as all connections should be checked at this stage if an "Opening a door" is causing such problems, there is a purple 1.0mm DC wire connection from relay No 2 and piggy backed from relay No 1 (connection No 85 on both relays) to the AES which may be loose.Hope this helps,Regards,Brendan Link to comment Share on other sites More sharing options...
peacock312 Posted August 23, 2012 Share Posted August 23, 2012 it says in my book,If the fridge does not automaticaly select GAS,turn off the fridge,then turn it back on again,if the gas supply is ok,then you should be ok.this is very important AFTER gas has been turned,IE after changing a bottle etc Link to comment Share on other sites More sharing options...
Brian Kirby Posted August 23, 2012 Share Posted August 23, 2012 Or, has the 12V supply to the fridge control panel fallen below 11V? It states that this, too, is monitored, and the fridge will seek gas in that event also. However, a yellow light should illuminate on the front panel if either 230V or 12V supplies fall below spec. I'm just wondering if the habitation battery is not getting charge, or is knackered, so just opening the door and illuminating the interior light, in addition to having turned on the fridge, is causing a borderline voltage drop below the threshold. I also wonder if a poor 12V supply or return connection might have the same effect. Might be a good idea for Marvin to just check that other 12V items (lights etc) are up to scratch. That should eliminate the battery as the source of the problem, but obviously not a bad 12V side connection somewhere. Link to comment Share on other sites More sharing options...
Mel B Posted August 23, 2012 Share Posted August 23, 2012 starvin marvin - 2012-08-23 8:49 AM Mel B - 2012-08-22 11:33 PM starvin marvin - 2012-08-22 7:57 PM The van is usually parked on the drive without EHU. When we get ready to go away I plug in the EHU to cool the fridge, which has been left switched off with the door ajar and the gas is turned off. The fridge door is then closed and switched on, all the correct lights are showing, and the fridge cools properly. When we start loading the fridge, ie opening the door, the fridge starts to look for gas, the solenoid "clicks" can't find gas and the red warning light comes on and keep "clicking". We then turn off the fridge and turn on the gas. The fridge is then switched on and immediately all the correct lights are on and the "clicking" stops and the fridge is cooling again. After turning the fridge to 'auto' mode and just prior to loading it do you disconnect the mains and move the van at all? If so, it would normally mean that the fridge would change over to 12v whilst the engine was running, then as soon as you stopped and turned off the ignition it would stop working as they have a safety 'cut-out' which prevents them from working on gas for around 15-20 minutes so that if you've gone to a petrol station it doesn't ignite the gas whilst you're filling up! It could then be that you are loading it up with food etc at around the time when the fridge automatically starts up again - as the mains has been disconnected, and the engine isn't running, it would then go to the only power source remaining - ie gas. Apologies if I wasn't clear. The fridge is not turned to "auto" mode, it is an automatic fridge. I believe AES stands for Automatic Energy Selection. At no time when getting the van ready is the engine started, the ignition is never turned on, nor is the EHU disconnected, or switched off. All we have done on the two occassions we've noticed this happening is turn the fridge off, ie press the on/off button, turn the gas on, light one of the gas rings to ensure gas is there. Then simply press the on/off button again and the correct fridge lights come on and its cooling again. When we had an AES fridge that was obviously younger than yours, we had the option of having it on auto so it selected the power source itself, of we could manually select the source, which is what Derek has pointed out above, hence why I didn't realise that the older type of AES fridge didn't have this option. I would do the following in the order below: 1) check that the 230v lead isn't damaged and that the end plugs are still correctly wired up with no lose wires which could be moving and causing a break in the supply (good practice to do this periodically anyway as they can become loose or get damaged in use). 2) plug the 230v lead into the camper and plug in a light to a 230v socket in the motorhome and switch on, then waggle the lead in the inlet in the side of the camper and see if the light flickers etc, if so then it could be the inlet socket. 3) get the electrical connections of the fridge checked to ensure they are 'tight' - it could be that the movement caused by you opening the fridge door is enough to cause an interruption of the 230v supply due to a bad contact/loose connection, and therefore it tries to go to gas as the only other source available. Link to comment Share on other sites More sharing options...
sheer lunar-see Posted August 24, 2012 Share Posted August 24, 2012 Hi also check your polarity on ehu, as thi can play havoc with the pcb on the control panel, well it did mine, and ended up fitting a new board, after I found that the internal wiring to the fridge had been incorectly wired. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted August 25, 2012 Share Posted August 25, 2012 sheer lunar-see - 2012-08-24 9:09 PM Hi also check your polarity on ehu, as thi can play havoc with the pcb on the control panel, well it did mine, and ended up fitting a new board, after I found that the internal wiring to the fridge had been incorectly wired. Plainly, if a fridge is incorrectly wired, consequential problems are pretty much inevitable. However, the polarity of a 230V EHU should not have an adverse effect on a correctly wired fridge. Although there can be fear and trembling among UK caravanners/motocaravanners when it comes to EHU reverse polarity, 'Continentals' don't care and Continental-built motorhomes need to be immune to back-to-front EHU polarity. I think starvin marvin has a Hymer B-Class and (based on the fridge model) it's going to be of pre-2005 vintage. It would appear that this peculiarity of switching spontaneously from 230V to gas when the fridge-door is opened has happened twice, but it's not been made clear whether this is now what always happens or whether the fridge mostly stays on 230V when its door is opened. The description of the installation strongly suggests that other-than-superficial technical investigation will require removal of the fridge. Some checks can be made regarding the EHU and 12V voltages but, if these show nothing unusual when the fridge tries to switch to gas when the door is opened, then one might anticipate the cause lies in the fridge's control electronics. Me, if it's possible to work around what the fridge is now doing (as starvin marvin seems able to do) and the fridge otherwise functons as expected, I'd leave matters alone. It's definitely odd, and not how one would envisage a 6-Series Dometic fridge behaving, but it could be a costly exercise to correct. Link to comment Share on other sites More sharing options...
Mel B Posted August 25, 2012 Share Posted August 25, 2012 Just a thought - assuming it is the type with a light in the fridge itself (oooo, I do miss my big fridge/freezer! :-| ) I wonder if when you open the door the light comes on and that is what is causing the problem? Try removing the bulb and see if it still does it. If so, then that's not the problem, if not, then it could be something to do with a faulty bulb fixing/bulb ... I may, of course, be talking absolute b*llocks! :D Link to comment Share on other sites More sharing options...
Derek Uzzell Posted August 25, 2012 Share Posted August 25, 2012 Worth a try. The manual indicates that an RM6405L has an interior light and Brian Kirby suggested earlier that this may be a factor in the fridge's peculiar behaviour. Now that starvin marvin has access to the manual for his fridge, what he needs to do is follow the manual's instructions and systematically analyse what the fridge does when an EHU is connected, when the motorhome's engine is started, when the door is open(ed) or shut, etc. Link to comment Share on other sites More sharing options...
onecal Posted August 26, 2012 Share Posted August 26, 2012 Hi ,The `12V supply can fall below 12V if the purple wires of the relays are loose (off connections No 85 on both relays) the may have been disturbed when working the fridge and on opening the door the internal fridge light may just be dropping the DC voltage below 11V . This will make the AES look for Gas, Any loose connection on the AC side can may also cause similar problems (voltage drop below 190/200v AC) will also cause the AES to look for GasRegards,Brendan Link to comment Share on other sites More sharing options...
Silicongyro Posted August 26, 2012 Share Posted August 26, 2012 Stavin Sorry to be a little late on this thread, as just got back to reviewing the forum. I have a 2004 Laika Kreos. This is fitted with a fridge exactly the same model as yours. A couple of years ago I had a problem very similar to yours. I would connect mains to the van to charge up the battery to full, and to cool down the fridge prior to a trip. Intermittently during this time the fridge would switch from mains to gas - even though mains was still available. This became more and more prevalent and would always be cured for a while by switching the fridge off for 20 secs and back on again. Then a little later it would switch to gas again! This was all nothing to do with fridge door being opened. Being an ex electronics engineer I set about sorting it out, and connected monitors to the electronics control board situated above the fridge freezer compartment (accessed by unscrewing the control panel and sliding this forward and out, then unscrewing the electronics control board behind). The problem was a relay associated with mains sensing intermittently failing. Unfortunately this relay, and all other electronic parts on the printed circuit board were encapsulated in a coating of plastic resin which makes component level repair near to impossible. I eventually replaced the complete electronics control board - obtained from Partmaster. I suspect you have a similar problem and in your case opening your fridge door is simply vibrating the failing relay contacts. During my investgation I happened across some USA RV forums, where they described similar issues with a 110v version of the control board used. They had been so troubled with the control board that a third party company was supplying plug replaceable equivalents ! So, try to knock/tap the top control panel to see if that stimulates the fridge into seeking gas ! Now so paranoid that I have left the monitors in place (3 leds) so that I always know what power source the AES system is wanting to use ! regards silicongyro Link to comment Share on other sites More sharing options...
onecal Posted August 27, 2012 Share Posted August 27, 2012 This is the last thing you want to replace, before ensuring there are no loose connections as I have given in previous replies.Check everything else first, but yes the boards do go down giving a number of differing faults,Regards,Brendan http://i1168.photobucket.com/albums/r497/onecal1/0bad5710.jpg?t=1346103539 Link to comment Share on other sites More sharing options...
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