Thetford Fridge 3-Way on Gas
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Markd
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The @Jenrai photo is N175 manual energy selection control board according to Jacksons.
www.jacksonsleisure.com
The @wildebus Photo is for N4000 series but it does look as if connections match Jenrai institu photo.
Have you tried cleaning and adjusting the electrode and convinced yourself that it is the board?
Anyway it looks like controller is available unlike the 'expert' thought - tbf the original green board unit has been superseded so a check on original part number would come up with not available
Thetford Caravan Fridge SR Powerboard R2G - Manual Energy Selection
Jacksons Leisure supplies a wide range of genuine Thetford parts. The Thetford Spare SR Fridge Powerboard R2G Electric is sent on a next day service
www.jacksonsleisure.com
The @wildebus Photo is for N4000 series but it does look as if connections match Jenrai institu photo.
Have you tried cleaning and adjusting the electrode and convinced yourself that it is the board?
Anyway it looks like controller is available unlike the 'expert' thought - tbf the original green board unit has been superseded so a check on original part number would come up with not available
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wildebus
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The thing is the board Jenrai got is not the right one. Pretty sure she will have a Auto fridge from the description of the issue.The @Jenrai photo is N175 manual energy selection control board according to Jacksons.
Thetford Caravan Fridge SR Powerboard R2G - Manual Energy Selection
Jacksons Leisure supplies a wide range of genuine Thetford parts. The Thetford Spare SR Fridge Powerboard R2G Electric is sent on a next day service
The @wildebus Photo is for N4000 series but it does look as if connections match Jenrai institu photo.
Markd
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Jenrai
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From extensive research I need the part no. 692247 (replaces 691101). I also think I found a techie to fit it. So I returned the other pcb but they dont have the one I need. Jackson leisure have them but delivery is 3-5 days. Honestly, why can't life be simple.
One things for sure I am 100% going to be at the New Forest meet even if I have to bring powdered milk and tin food
One things for sure I am 100% going to be at the New Forest meet even if I have to bring powdered milk and tin food
wildebus
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Fridge uprighted again 
(quite a bit of gurgling going on when turned back over - think that is to be expected?)
Transferred the two temp sensors into it to monitor;
Connected 12V (for the fridge electronics) to spare battery;
Connected 240AC to external AC outlet in Motorhome so I can see how it runs and if any power cycling occurs.
Switched on at 17:00 - what will happen!
(quite a bit of gurgling going on when turned back over - think that is to be expected?)Transferred the two temp sensors into it to monitor;
Connected 12V (for the fridge electronics) to spare battery;
Connected 240AC to external AC outlet in Motorhome so I can see how it runs and if any power cycling occurs.
Switched on at 17:00 - what will happen!
Markd
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Glad to hear that you are making progress and that with a bit of luck you'll be up and running again in a week.From extensive research I need the part no. 692247 (replaces 691101). I also think I found a techie to fit it. So I returned the other pcb but they dont have the one I need. Jackson leisure have them but delivery is 3-5 days. Honestly, why can't life be simple.
One things for sure I am 100% going to be at the New Forest meet even if I have to bring powdered milk and tin food
wildebus
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Looks like a bit of a change in operation?
This is a 24-hour view ... only relevant from 17:00 onwards when I turned the fridge back on. Check out the temp drop for the Freezer in under two hours ....
go for a zoom to the last hour ....
A drop from 18.7C to 2.9C in 60 minutes is looking pretty nice?
There is frost and a touch of ice on the back wall of the freezer compartment.
Now someone said when the Fridge is first turned on, the Freezer compartment effectively gets priority and only then the main fridge section starts to cool? Makes sense and I am hoping that is how it works as the fridge is not so fast in chilling from startup
Just have to wait and see, but the fins in the fridge do feel colder then the last time I had this running in the Motorhome, so it is promising
This is a 24-hour view ... only relevant from 17:00 onwards when I turned the fridge back on. Check out the temp drop for the Freezer in under two hours ....
go for a zoom to the last hour ....
A drop from 18.7C to 2.9C in 60 minutes is looking pretty nice?
There is frost and a touch of ice on the back wall of the freezer compartment.
Now someone said when the Fridge is first turned on, the Freezer compartment effectively gets priority and only then the main fridge section starts to cool? Makes sense and I am hoping that is how it works as the fridge is not so fast in chilling from startup
Just have to wait and see, but the fins in the fridge do feel colder then the last time I had this running in the Motorhome, so it is promising
mistericeman
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A lot of the absorbtion fridge types only have the evaporator as the freezer compartmentLooks like a bit of a change in operation?
This is a 24-hour view ... only relevant from 17:00 onwards when I turned the fridge back on. Check out the temp drop for the Freezer in under two hours ....
View attachment 60422
go for a zoom to the last hour ....
View attachment 60423
A drop from 18.7C to 2.9C in 60 minutes is looking pretty nice?
There is frost and a touch of ice on the back wall of the freezer compartment.
Now someone said when the Fridge is first turned on, the Freezer compartment effectively gets priority and only then the main fridge section starts to cool? Makes sense and I am hoping that is how it works as the fridge is not so fast in chilling from startup
View attachment 60424
Just have to wait and see, but the fins in the fridge do feel colder then the last time I had this running in the Motorhome, so it is promising
Relying on cold air dropping to lowest point....
And to be honest some smaller compressor fridges do the same.
Markd
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Impressive turn round of performance! 
I'm half tempted to take mine out and do the same thing as whilst I've been happy enough in the past it's hardly been used for 18 months and I wasn't that impressed when I turned it on last week.
I suppose it's a no lose option if I can wrestle it out and over by myself.
It may have to wait as I'm refitting our bathroom at the moment and I'm not sure SWMBO would appreciate it!
I'm half tempted to take mine out and do the same thing as whilst I've been happy enough in the past it's hardly been used for 18 months and I wasn't that impressed when I turned it on last week.
I suppose it's a no lose option if I can wrestle it out and over by myself.
It may have to wait as I'm refitting our bathroom at the moment and I'm not sure SWMBO would appreciate it!
wildebus
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Did final check for the night ... Been running for just under 4 hours now on AC.
The Freezer is down to -9C now
A drop of 28C in 4 hours is pretty good going I think.
And now the Freezer is very cold, the Fridge has started doing its cooling as well - now down below 10C
Took a bit of time initially
But this shows the last hour
Will see what is happening in the morning - and if the 240V did any cycling on and off.
Next step will be to connect the 12V supply and see if the temp is maintained (the best that is expected on a 3-Way apparently).
Then followed by turning off and let it go back to room temp and then running on gas to compare (bit trickier to do as fridge in a shed and need to vent the exhaust, so have to think about this one a bit. I have some flexible exhaust piping I could put over the chimney top to vent)
Weirdly, from what I have seen so far, especially with the way the freezer is working, I am tempted to actually refit the thing!
If the fridge didn't work then it would be a simple decision to maybe sell it off as a project for someone, or break it down for a few spare parts to sell off, and scrap the rest but if it is working just as it is meant to, it would be a shame to do that considering how much these cost to buy new!
Anyone need a top of the range (in 2008) 3-Way Fridge?
The Freezer is down to -9C now
A drop of 28C in 4 hours is pretty good going I think.
And now the Freezer is very cold, the Fridge has started doing its cooling as well - now down below 10C
Took a bit of time initially
But this shows the last hour
Will see what is happening in the morning - and if the 240V did any cycling on and off.
Next step will be to connect the 12V supply and see if the temp is maintained (the best that is expected on a 3-Way apparently).
Then followed by turning off and let it go back to room temp and then running on gas to compare (bit trickier to do as fridge in a shed and need to vent the exhaust, so have to think about this one a bit. I have some flexible exhaust piping I could put over the chimney top to vent)
Weirdly, from what I have seen so far, especially with the way the freezer is working, I am tempted to actually refit the thing!
If the fridge didn't work then it would be a simple decision to maybe sell it off as a project for someone, or break it down for a few spare parts to sell off, and scrap the rest but if it is working just as it is meant to, it would be a shame to do that considering how much these cost to buy new!
Anyone need a top of the range (in 2008) 3-Way Fridge?
Jenrai
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Got a techie coming to look tomorrow, i'll see what happens from that. But thanks for offer
Markd
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Dometic say you can expect some temperature regulation on mains and gas but not 12v.
As I said earlier you can hear a thermostat click run-out when turning my old 'mechanical' fridge temp dial so presumably there would be some cycling.
The current on 12v is far too high to put through a thermostat and if I remember correctly the element wattage is lower so constant duty is used.
I can see how a capillary bulb could partially close the gas supply and reduce cooling effort.
On an electronically controlled fridge the gas could be turned off and relit I suppose.
I think mine just sets a constant flame dependent on the position of the temperature knob because after an extended time on gas I have to ease it off as the fridge gets too cold.
As I said earlier you can hear a thermostat click run-out when turning my old 'mechanical' fridge temp dial so presumably there would be some cycling.
The current on 12v is far too high to put through a thermostat and if I remember correctly the element wattage is lower so constant duty is used.
I can see how a capillary bulb could partially close the gas supply and reduce cooling effort.
On an electronically controlled fridge the gas could be turned off and relit I suppose.
I think mine just sets a constant flame dependent on the position of the temperature knob because after an extended time on gas I have to ease it off as the fridge gets too cold.
Markd
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Well you did say never say never
They are good bits of kit but very heavy on electricity.
A few hundred grammes of gas per day isn't too bad and goes a long way towards balancing the cost of a purpose made 12v compressor fridge.
But if you've already got the electrical capability to support it a sub £300 domestic fridge freezer does make sense long term.
wildebus
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So been 15 hours since fridge restarted post "right-ended"
This is the Fridge Temp ...
Looks spot on.
The setting on the control panel is right in the middle (3 bars). The ripple that starts from around 23:00 is the power cycling of the AC input. So there is some kind of control going on.
And the Freezer Section
Nice consistant temp there once initially cooled down. Same ripple for same reason of course.
These Temp Sensors I have to say are brilliant And as a Brucie Bonus, they have a feature which turns out to be excellent for this kind of monitoring.
Right now I am monitoring the power via Victrons VRM Portal. I can do the same when I switch to 12V for testing. But when it comes to checking on LPG, VRM is no use. But these Sensors don't just log temperature, they log humidity also.
In the fridge, when the cooling is active, the water is drawn out the air and settles on the cooling fins inside the fridge body as frost and ice, lowering the humidity. When the cooling stops, the fins gradually warm and water is 'released' making the air more humid.
This is the full screen in the Sensor App.
And Here is a zoom-in with the power use added on the same time line
What this means is that you can get a good idea from the Humidity chart if there is active (i.e. Powered) cooling going on or not, and this will be true of Gas as well as Electricity.
In the case of my fridge, there is no pilot light - on Gas, when there is a cooling demand the gas will ignite and then turn off when demand is removed, just like the Electric cycling.
Well that is how it is meant to work I believe the Humidity graph will confirm that I guess
(In terms of the Energy Efficiency labels you see on Applicances, the 94L compressor fridge I have installed as a temporary measure quotes 84kWh/Annum. This 3-Way would be 1,200kWh/Annum!)
So I am seeing a calculated average of around 3.3kWh/24Hrs on AC. There is no doors being opened to take out/out in food, so the likely consumption would be greater.
The Manual for my N180 Model states a consumption of 3.7kWh/24 Hours, so what I am seeing I think it pretty well on the money (which is good as it would confirm it is working correctly on AC). The Manual quotes a GAS consumption of 400gr/24Hours. There is close enough 2L of gas per 1Kg, so call that 0.8L LPG
Doing the maths, 3.7kWh = 62.9p (@17p/kWh); 0.8L of LPG = 54p for Refillable @68p/L (what I pay) or £1.23 for Calor (13Kg Refill @ £40)
A mid-size (150L or so) Compressor Fridge/Freezer you could expect to use 500Wh/24 hours, costing 8.5p to run - If you were to plug in your Motorhome fridge at home 24/7 for a year whenever you are not using it, the 3-Way would for a full year cost just under £200 MORE to run (£229 vs £31)
Cost of a 3-Way for a wild-camper using Calor .... £1.15 extra a day; Using LPG .... 60p more a day. Useful to know to consider if fitting a refillable would actually save money including the kit itself.
This is the Fridge Temp ...
Looks spot on.
The setting on the control panel is right in the middle (3 bars). The ripple that starts from around 23:00 is the power cycling of the AC input. So there is some kind of control going on.
And the Freezer Section
Nice consistant temp there once initially cooled down. Same ripple for same reason of course.
These Temp Sensors I have to say are brilliant
And as a Brucie Bonus, they have a feature which turns out to be excellent for this kind of monitoring.Right now I am monitoring the power via Victrons VRM Portal. I can do the same when I switch to 12V for testing. But when it comes to checking on LPG, VRM is no use. But these Sensors don't just log temperature, they log humidity also.
In the fridge, when the cooling is active, the water is drawn out the air and settles on the cooling fins inside the fridge body as frost and ice, lowering the humidity. When the cooling stops, the fins gradually warm and water is 'released' making the air more humid.
This is the full screen in the Sensor App.
And Here is a zoom-in with the power use added on the same time line
What this means is that you can get a good idea from the Humidity chart if there is active (i.e. Powered) cooling going on or not, and this will be true of Gas as well as Electricity.
In the case of my fridge, there is no pilot light - on Gas, when there is a cooling demand the gas will ignite and then turn off when demand is removed, just like the Electric cycling.
Well that is how it is meant to work I believe
the Humidity graph will confirm that I guess It works out in this instance to be 25 Minutes on, 15 minutes off, so just over a 60:40 on/off cycle making the average power use 137Wh/Hr. Even with this power cycling, the daily power consumption on AC is 3.3kWh.Well you did say never say never
They are good bits of kit but very heavy on electricity.
A few hundred grammes of gas per day isn't too bad and goes a long way towards balancing the cost of a purpose made 12v compressor fridge.
But if you've already got the electrical capability to support it a sub £300 domestic fridge freezer does make sense long term.
(In terms of the Energy Efficiency labels you see on Applicances, the 94L compressor fridge I have installed as a temporary measure quotes 84kWh/Annum. This 3-Way would be 1,200kWh/Annum!)
So I am seeing a calculated average of around 3.3kWh/24Hrs on AC. There is no doors being opened to take out/out in food, so the likely consumption would be greater.
The Manual for my N180 Model states a consumption of 3.7kWh/24 Hours, so what I am seeing I think it pretty well on the money (which is good as it would confirm it is working correctly on AC). The Manual quotes a GAS consumption of 400gr/24Hours. There is close enough 2L of gas per 1Kg, so call that 0.8L LPG
Doing the maths, 3.7kWh = 62.9p (@17p/kWh); 0.8L of LPG = 54p for Refillable @68p/L (what I pay) or £1.23 for Calor (13Kg Refill @ £40)
A mid-size (150L or so) Compressor Fridge/Freezer you could expect to use 500Wh/24 hours, costing 8.5p to run - If you were to plug in your Motorhome fridge at home 24/7 for a year whenever you are not using it, the 3-Way would for a full year cost just under £200 MORE to run (£229 vs £31)
Cost of a 3-Way for a wild-camper using Calor .... £1.15 extra a day; Using LPG .... 60p more a day. Useful to know to consider if fitting a refillable would actually save money including the kit itself.