- Dec 22, 2018
- 364
- 327
- Funster No
- 57,664
- MH
- Hymer Classic B584
- Exp
- Since 2019
Hi. I've had a 2002 Hymer Classic B584 for a season and fitted solar to it. I'm fairly competent mechanically and technically, but the finer points of electrics are not something I do often enough to warrant learning it. I use my Hymer in the warmer months for long periods. My current leisure setup fulfils my use now.
My Hymer has an EBL 99 (capable of 10 Amps solar & 16 Amps alternator charging I think). I installed 200 watts of solar through a Votronic Duo Digital 250 (with temp lead & LCD display), but direct from Votronic to the Yuasa EFB-36 100Ah leisure battery (LB). I did this rather than connect it via the EBL because the solar limit of the EBL is 10 amps. The spec's of the 2 panels combined showed just over 11 amps max (but as it is I could have done it as they didn't get near that). Anyway it all seems to have worked fine, though the 12 volts on my 3 way fridge did finally die, but I think that was just coincidence. 4 months of a long hot summer were too much for it.
I had the AES control from the Votronic solar controller connected to the fridge. This signals the fridge to run off the LB when there is excess solar power. It would only ever run like that for a few minutes - maybe 5 mins max (drawing 10 amps). I do wonder if bypassing the EBL could have caused trouble? Could that have over powered the fridge control panel? But surely that's no different to when you're driving and it's running off the alternator, or would the fridge have better voltage control coming via the EBL? The Votronic's max solar charge voltage is 14.4. If that went through to the fridge could that have cooked the control panel?
The fridge is not economic to fix mostly because the suspected faulty part (the main control panel & front panel - Dometic RM6405) is unavailable. Yes, I (and a motorhome repair bloke) have looked into all possibilities, but it's a no go. Besides that, it was pretty rubbish last summer in 25-37 degrees.That's just a limitation of an absorption fridge. The space is under bench and has an upper and lower vent to outside.
Right, so I'm looking at about £1000 for supply and fit of a new 3 way. That (and better fridge performance) got me thinking of a compressor fridge - either 12 volt, or 240 volt via inverter, with an extra solar system to drive it.
My thinking is rather than enlarge the current solar system, which runs all the usual leisure stuff, I'd install a separate system just to run the fridge. A couple of reasons - to save replacing stuff which is installed and working, and a bigger system would most likely be beyond the capacity of the existing EBL/vehicle charging system. Also so the fridge won't exhaust the normal leisure workings.
I'm thinking:
200 watts fixed solar (with another 100 watt panel to use on the ground as a portable unit in inclement weather)
Votronic Duo Digital 430 solar controller (with LCD display and temp lead)
Votronic 30A B2B charger (with LCD display near driver seat)
Yuasa EFB-36 100Ah battery (possibly two) or 1 Exide ES900 Gel. Open to battery suggestions?
The gel battery has more cycles, can be discharged lower, but doesn't like heat and has a low recharge rate (20A). One gel battery would provide nearly as much capacity as two lead acid ones with less weight and space used. A bit cheaper too.
Victron mains charger 30A - can run lower (I already have this).
Option 1.
12 volt compressor fridge -
Isotherm Freeline 115 Elegance £799
<Broken link removed>
A really nice spec, low amp fridge. The freezer only goes down to -8, but that's enough for my use.
267 watts per 24 hour @ 25 degrees = 22.25 ah per day
Total cost including fridge, batteries & 200 watts solar £1830!
or
Option 2.
A standard domestic 240 volt fridge that'll fit in the space, run via Victron Phoenix inverter as I already have a 500VA one. These can run in 'eco mode' using less standby power. The eco mode might work for a fridge (yes - confirmed elsewhere). Or there's a technique to wire an inverter up to the fridge thermometer so there is no standby draw (need to look into that).
I was considering this fridge, but wasn't sure if it would be low enough to fit:
www.inventorappliances.com
£105 A++ Not sure of the power usage in DC. They state 0.36 kWh per day @ 240 volts I can't work out the equivalent in DC.
You can remove the top which may gain enough to fit it in. What I'm not sure about with a domestic fridge is do they use the sides/top to expel heat or would the existing vents in my Hymer (at top & bottom rear of fridge space) be ok to cool it (possibly with extra fans)? All the installation instructions for house fridges require space all round but that's assuming being installed in an unvented space/room. If you just ventilate the rear, where the compressor is, to the outside, is that ok?
Older style fridges have a cooling 'radiator' panel on the back, but more modern ones seem to only have a small opening around the compressor, so where do they expel the heat?.
Total for that 240 volt fridge including fridge and 2 batteries/200 watts solar about £1200. A lot less than 12 volt. Even to allow for inverter losses, so bigger solar, that is a big difference.
Then I found the following fridge, which although more expensive, is exactly the right size to fit (hopefully) €355 (£300) delivered. It also has great specs, very low power use as it's A+++. 0.254 KwH per day @ 240 volts. So I got that one off ebay.
www.beko-hausgeraete.de
I'd also thought of putting a switch like this in between fridge and all batteries (the new setup and the existing leisure one) so I could pick which solar setup (battery) supplied the fridge. Just in case I ran the fridge system battery too low, but still had reserve in the standard LB.
Payload is a consideration, but I think I have plenty of excess to handle it.
Also considering a battery protection doo dah so the fridge battery doesn't get depleted overnight.
I've discussed this on another forum already which has answered some questions. A few people do use 240 volt fridges fine. I suppose I'm after anyone else that has and if there might be any issues not covered - particularly complications working in with the Hymers existing systems. I've tried to minimise these by separating the fridge system from the existing as much as possible. It really will only connect at the alternator and if I install the 4 way switch which can allow the fridge to run off either leisure system.
My Hymer has an EBL 99 (capable of 10 Amps solar & 16 Amps alternator charging I think). I installed 200 watts of solar through a Votronic Duo Digital 250 (with temp lead & LCD display), but direct from Votronic to the Yuasa EFB-36 100Ah leisure battery (LB). I did this rather than connect it via the EBL because the solar limit of the EBL is 10 amps. The spec's of the 2 panels combined showed just over 11 amps max (but as it is I could have done it as they didn't get near that). Anyway it all seems to have worked fine, though the 12 volts on my 3 way fridge did finally die, but I think that was just coincidence. 4 months of a long hot summer were too much for it.
I had the AES control from the Votronic solar controller connected to the fridge. This signals the fridge to run off the LB when there is excess solar power. It would only ever run like that for a few minutes - maybe 5 mins max (drawing 10 amps). I do wonder if bypassing the EBL could have caused trouble? Could that have over powered the fridge control panel? But surely that's no different to when you're driving and it's running off the alternator, or would the fridge have better voltage control coming via the EBL? The Votronic's max solar charge voltage is 14.4. If that went through to the fridge could that have cooked the control panel?
The fridge is not economic to fix mostly because the suspected faulty part (the main control panel & front panel - Dometic RM6405) is unavailable. Yes, I (and a motorhome repair bloke) have looked into all possibilities, but it's a no go. Besides that, it was pretty rubbish last summer in 25-37 degrees.That's just a limitation of an absorption fridge. The space is under bench and has an upper and lower vent to outside.
Right, so I'm looking at about £1000 for supply and fit of a new 3 way. That (and better fridge performance) got me thinking of a compressor fridge - either 12 volt, or 240 volt via inverter, with an extra solar system to drive it.
My thinking is rather than enlarge the current solar system, which runs all the usual leisure stuff, I'd install a separate system just to run the fridge. A couple of reasons - to save replacing stuff which is installed and working, and a bigger system would most likely be beyond the capacity of the existing EBL/vehicle charging system. Also so the fridge won't exhaust the normal leisure workings.
I'm thinking:
200 watts fixed solar (with another 100 watt panel to use on the ground as a portable unit in inclement weather)
Votronic Duo Digital 430 solar controller (with LCD display and temp lead)
Votronic 30A B2B charger (with LCD display near driver seat)
Yuasa EFB-36 100Ah battery (possibly two) or 1 Exide ES900 Gel. Open to battery suggestions?
The gel battery has more cycles, can be discharged lower, but doesn't like heat and has a low recharge rate (20A). One gel battery would provide nearly as much capacity as two lead acid ones with less weight and space used. A bit cheaper too.
Victron mains charger 30A - can run lower (I already have this).
Option 1.
12 volt compressor fridge -
Isotherm Freeline 115 Elegance £799
<Broken link removed>
A really nice spec, low amp fridge. The freezer only goes down to -8, but that's enough for my use.
267 watts per 24 hour @ 25 degrees = 22.25 ah per day
Total cost including fridge, batteries & 200 watts solar £1830!
or
Option 2.
A standard domestic 240 volt fridge that'll fit in the space, run via Victron Phoenix inverter as I already have a 500VA one. These can run in 'eco mode' using less standby power. The eco mode might work for a fridge (yes - confirmed elsewhere). Or there's a technique to wire an inverter up to the fridge thermometer so there is no standby draw (need to look into that).
I was considering this fridge, but wasn't sure if it would be low enough to fit:
Compact Refrigerator in modern silver colour and 98L of capacity
Compact refrigerator, silver, of 98lt capacity and new energy class is the ideal solution for small rooms or offices, by Inventor Appliances.
£105 A++ Not sure of the power usage in DC. They state 0.36 kWh per day @ 240 volts I can't work out the equivalent in DC.
You can remove the top which may gain enough to fit it in. What I'm not sure about with a domestic fridge is do they use the sides/top to expel heat or would the existing vents in my Hymer (at top & bottom rear of fridge space) be ok to cool it (possibly with extra fans)? All the installation instructions for house fridges require space all round but that's assuming being installed in an unvented space/room. If you just ventilate the rear, where the compressor is, to the outside, is that ok?
Older style fridges have a cooling 'radiator' panel on the back, but more modern ones seem to only have a small opening around the compressor, so where do they expel the heat?.
Total for that 240 volt fridge including fridge and 2 batteries/200 watts solar about £1200. A lot less than 12 volt. Even to allow for inverter losses, so bigger solar, that is a big difference.
Then I found the following fridge, which although more expensive, is exactly the right size to fit (hopefully) €355 (£300) delivered. It also has great specs, very low power use as it's A+++. 0.254 KwH per day @ 240 volts. So I got that one off ebay.
Beko Hausgeräte | Home
Europas beliebteste Marke für Haushaltsgeräte. Benutzerfreundliche Produkte & innovative Technologien für die ganze Familie. Jetzt entdecken!
I'd also thought of putting a switch like this in between fridge and all batteries (the new setup and the existing leisure one) so I could pick which solar setup (battery) supplied the fridge. Just in case I ran the fridge system battery too low, but still had reserve in the standard LB.

Marine Battery Isolator/Changeover Switch - 4 Positions - 100A Cont.
4 position marine battery isolator / changeover / master switch for boats, cars & other vehicles. 100A continuous, 500A for 5 secs.
www.12voltplanet.co.uk
Payload is a consideration, but I think I have plenty of excess to handle it.
Also considering a battery protection doo dah so the fridge battery doesn't get depleted overnight.
I've discussed this on another forum already which has answered some questions. A few people do use 240 volt fridges fine. I suppose I'm after anyone else that has and if there might be any issues not covered - particularly complications working in with the Hymers existing systems. I've tried to minimise these by separating the fridge system from the existing as much as possible. It really will only connect at the alternator and if I install the 4 way switch which can allow the fridge to run off either leisure system.