Hi Jeremy,
- I've only just seen your post and there's been lots of posts subsequently.
- My installer would only fit a 75Ltr LPG tank as they believed (rightly or wrongly) that anything bigger would fall outside the guidance given in the LPGA (LPG Assosciation as was - now something else) Code of Practice No11 - please note, the COP is not mandatory - it is guidance only, but could explain why a lot of installers shy away from the vapour take-off idea?
- For similar reasons the same installer was against an LPG vapour takeoff as this would require re-fabricating the Original Equipment Manufacturer's LPG tank thus voiding any warranty and pressure testing given by the tank's, manufacturer.
- I did consider at one time of 'upgrading' to a larger tank and also a vapour take-off but the cost of fitting a replacement tank with a vapour takeoff would likely come it at around £500 I should think. After considering my use and hence the payback period, I decided against this option.
- I think that LPG tanks require changing after 10 years iirc (?), so that might be a time to re-consider?
- Personally I have a 4.5Kg Calor Butane bottle for cooking and heating. I only use the Propex occasionally so I can't give you any true indication of how long the cylinder lasts. In my 5 years of using the camper, mainly in warmer climes and/or electric hookup, I've changed the bottle just twice, maybe 3 times (so a loooong way from £500)
- Propex do a heater with a built in electric heater module which might be something to consider and which on reflection I should have gone for - @Lize has one - she might be along to comment on this?
The LPGA (LPG Association) was a trade body set up for the likes of gas refineries and suppliers such as Calor Gas, it has never been relevant to vehicles. SInce being called the LPGA it has changed name twice, first to UKLPG, it never was a European wide trade body and it would seem they wanted to convey that point in their name, and more recently to Liquidgas because it would seem that looking to the future they want to distance themselves from the term 'petroleum'... they can produce completely carbon neutral synthetic LPG and if you look on their website it gives the impression they have an eye to the far future when petrol vehicles will no longer be sold but the world will still need LPG, at least for making other things out of (plastics etc).
I have never supported this trade body, as implied they don't have motorists interests at heart, they only have the suppliers interests at heart. At least with petrol there are setups like the RAC and AA that lobby on the behalf of motorists, including lobbying on aspects such as fuel prices.... For motorists and garages to support this trade body is akin to having Shell lobby on the behalf on motorists, there is a complete conflict of interests, e.g. Why would Shell want lower fuel prices?
There is an existing BSEN (European wide) Standard that installers follow when converting vehicles to LPG, there was never a need for a trade body for gas suppliers to ever get involved with vehicle LPG conversion Standards and they are not involved with making vehicle LPG conversion Standards... But they like to give people the opinion that one of their voluntary 'standards' (inverted commas because it is not a legal Standard) is the Standard and they don't like to talk about what is actually the real Standard. One guy at (then) LPGA set up the whole department at LPGA that deals with LPG converted vehicles, Mike Chapman has told me to my face that he set it up for himself as a cushy number before his retirement and he agrees with many of the points I make. For most of the time of this department's existence there has only been Mike Chapman and his secretary but they have occasionally had someone else from the trade body help out. The department pays for itself because installer members have to pay subs to the trade body and the trade body charges around £17 for every vehicle that is put onto their database. Their database is not a legally recognised / official database, it is just a private database run by a trade body. Most installers simply ignore this trade body, I certainly do, only a minority of vehicle LPG installers are members of the trade body and only a very small fraction of LPG converted vehicles in the UK are on their private database. I find it strange that some of the installers in the UK whom came here from abroad tell their customers that they hold the trade body in good esteem... they didn't have such trade body in their home country but they still had to adhere to the BSEN in whatever country they came from and none are going to say that they had any more problems before their involvement with the trade body in this country than they had when they were not members of the trade body but were converting vehicles wherever they came from. The trade body tries to tell people that they won't be able to insure their vehicle if they have it converted to LPG and the conversion isn't listed on their database but that isn't true. There is only one official database of vehicles and their fuel types in the UK, it is the familiar scheme run by VOSA that supplies vehicle log book etc. It is a vehicle owner's responsibility to have the logbook changed if a vehicle's fuel type is changed, the law says owners 'must inform DVSA'. The trade body and their installer members don't usually tell their LPG conversion customers that they have a responsibility to change the fuel type on their logbook and when people don't change the fuel type on their logbook insurers will question why the logbook says 'petrol' when the engine actually runs on petrol or on LPG. The trade body's database means nothing officially... If you have had an LPG conversion and your vehicle is registered on the trade body's database but has not had the fuel type changed on the logbook there will be no concessions (now or future) for emissions zones but if the fuel type on the logbook has been changed there are current and may be further future concessions. For example if you have LPG as a fuel type on the logbook and you visit Paris you will get a discount (similar to an EV vehicle discount) if entering the emissions zone, if you don't have LPG as a fuel type on the logbook but your vehicle is listed on the private trade body's database you will pay the full price to enter Paris because officialdom doesn't recognise the trade body's database. When VOSA want to ask an LPG expert questions when planning changes to (e.g.) the MOT they don't ask the trade body, they ask me. One such question was should LPG converted vehicles be allowed to pass the MOT with the engine warning light on, the trade body and many of their members wanted the answer to be yes but I said no, the MOT scheme does not now allow LPG converted vehicles to pass if the engine warning light is on. A benefit to me in 2 ways... When I convert a vehicle the engine warning light doesn't come on but more importantly I know that if I'd said yes questions would have been asked within VOSA as to why an LPG converted vehicle should be allowed such special concession and then we could all have gone down the line of compulsory IVA or at least specific vehicle emissions tests. A detriment to many installers because when they convert a vehicle they may well have engine warning light problems.
The trade body's self imposed rules about tank size don't make any sense. Their self imposed rule is 8 inches of ground clearance below the tank but it is 8 inches if the vehicle is a lowered little sports car or a 40ft long RV or anything in-between! They have no list of the maximum size tank that can be fitted on a vehicle... Except for one! Guess what that one rule is? The one rule they have on maximum tank depth is that a tank shouldn't be deeper than 250mm on an E51 Elgrand! The reason for their exception regards Elgrands is because some of their members don't like me fitting the large tanks I fit on Elgrands (that are also 270mm deep)! Imagine if they had a list of vehicles versus maximum tank size that will fit... The list would have to include all the various specs of that model vehicle all of which might be at different ride heights, e.g. HighwayStar might be an inch higher ride height than a Rider so the list would have to include data that a tank one inch deeper could be fitted on the HighwayStar than on a Rider. It would be hard cheese for anyone who had lowered their Elgrand, for example fitted coil-over suspension because if trade body members followed the 8 inch rule on lowered Elgrands they might only fit a 30 litre tank lol. It would simply be an unworkable list. Imagine if a vehicle went to be looked at by 'one of their guys'... it might pass their test if unloaded but fail if it went for the same test with a sports bag in the luggage area, again an unworkable list. If this 8 inch rule of their is what they're trying to impose on Elgrands then their 250mm tank depth rule for E51's doesn't add up or make sense, because a 250mm depth tank will have a different ride height depending on the spec of the E51, also depend on whether or not the springs have sagged since new, also depend on whether or not aftermarket suspension such as lowered coilovers have been fitted. But let's suppose we went with the rule that the deepest tank that will fit on an Elgrand was 250mm deep, in that case they could still fit a 720mm x 250mm tank rated at 82 litres not 77 litres. And they could still purge air out of the tank to allow the tank to fill to the full capacity that the percentage fill limiter valve will allow (80%) even in cold weather conditions. And since the check wouldn't involve filling the tank from empty to see how much gas it would take and check on that 80% fill limit they could still adjust the valve to allow filling to 90%. They don't fit 720mm width tanks like I do on Elgrands, they fit 680mm or 650mm tanks. Alan if your tank is only rated at 77 litres and if they went by their own rules regards only tanks of up to 250mm depth should be fitted on E51's then they have only fitted a tank on yours that is 680mm diameter (77 litres corresponds to a 680x250 tank), when they could have fitted a 720mm x 250mm 84L tank and you would still have had more capacity without having less ground clearance. Any way you look at it they have short changed you on tank capacity... But the smaller tank will have been easier for them to fit. The 720mm tank I fit has to be fitted accurately, to a position within around 7mm of intended or it could foul the diff housing. In contrast to 7mm clearance with the 720mm tank, a 680mm diameter tank only has to be fitted within a range of around 47mm of intended position. Some installers will have first fitted a 650 tank for one or a few customers and then worked their way up to fitting a 680mm tank as their confidence at getting the position correct grew a bit, but a lot will have left it at 680mm instead of going up tp 720mm because they realise it would be a lot more work to get the tank position correct. Others will just have ruled out fitting a 720mm tank from the outset because they only measure 728mm and think it very difficult to fit a 720mm tank (if even possible). For me the sensible thinking about maximum depth and/or ride height of an LPG tank should be to ensure that it isn't any lower than any other point on the vehicle. Edit - When I am considering what size tank to fit on a vehicle I start out by doing the same as other installers... I measure up. But vehicles don't tend to have a lot of straight edges in the areas where tanks will be fitted and whether or not a tank of a given (or maybe bigger than expected) size will fit isn't always clear cut. In that sort of situation I'm likely to try offering up a bigger tank into position to see if it will fit and check clearances around it, it seems to me that once most other installers have offered a tank into position they're not going to lower that tank to try offering up a bigger tank even if it seems there's a chance of enough space and clearance. Sometimes I use a bit of maths to help determine if a tank will fit... Take measurements at various points on a curved area and then maybe use a mathematical formula (chord equation etc) to see if it seems the curve of a bigger LPG tank might take advantage of the extra space in a panel that has an area that curves away from the area where a tank will be fitted. Elgrands have a curved area in the rear panel, the 720mm tank takes advantage of that curved area, in contrast it seems a lot of installers measure up as though they're going to fit a square LPG tank that doesn't exist and I doubt they've ever used a chord function.
It is a grey area welding on tanks, it is even a grey area welding to existing tank brackets (the existing brackets that were welded to tanks at the factory when the tank was produced which usually have threaded holes etc to allow bolting the tank to the vehicle). But plenty installers including trade body members do weld to tanks anyway, at least to the brackets. Welding is one thing, pressure welding is another thing, you won't find many installers whom have been involved with pressure welding, I have been involved with it on power stations etc and I am confident and competent at pressure welding especially when we're only talking about welding a 12mm diameter fitting around a 2.5mm hole on a tank that will only ever see a max of 30bar pressure even if it was put on a bonfire and will only ever normally see up to around 10 bar pressure. I understand most installers not wanting to get involved with it and I understand the trade body imposing on their members that they don't do it but it can be done properly and safely and the tanks are produced by welding several sections together in the first place. Tanks are under nowhere near the amount of stress a lot of people seem to think they're under, they're at least 3mm thick but we can buy propane in cans similar to aerosol cans from the likes of B&Q that are less than 1mm thick. The pressure in a propane tank isn't a big concern, I would happily drill a hole through an LPG tank and stick my finger over the hole to stop the leak to demonstrate. I have on many occasion removed valves from tanks half full of gas, this leaves a 70mm hole in the tank, the gas gets very cold in the tank and you can see it sloshing around inside, even pour it on the floor and make a little stream of it.
Tank makers say tanks should be changed every 10 years and the BSEN standard says the same. But in practice there is nothing official to enforce this and as long as they don't get very rusty they are seldom replaced... LPG tanks are not a high pressure vessel (like for example an Oxygen tank or a CNG tank), they're never going to fail in a way that sees them explode. I have seen some very old externally fitted tanks leak in areas where they have rusted through (usually very old tanks on e.g. 4x4s that have been unprotected no paint on them for years and dipped in sea water launching boats etc), even tanks in such condition don't catastrophically fail, you usually notice a leak and then find bubbles when going around with leak detector spray and even if you hit them with a lump hammer you still couldn't knock a big hole in them, even if you could knock a big hole in them it wouldn't really be a problem.
I maintain that 720mm x 270mm 90+ litre rated tanks are by far the best tank option for E51 Elgrands. They're not the lowest point on the vehicle anyway, the diff, part of the exhaust, front crossmembers etc are all lower than the 270mm depth tank and there is no point in fitting a tank that is narrower than 720mm so doesn't take up all the available width that is available for a tank in the usual spare wheel location. The 90% tank mod makes sense too, even the red bottles that people use indoors (living rooms etc) to fuel gas fires (such as the old Super-Ser heaters) are filled to 90% of gross capacity and they sit in a heated living room right next to a gasfire (obvious and very definite heat and ignition source with a flame a couple of inches away from the bottle...) compared to LPG tanks on Elgrands that are outside and not next to an obvious ignition source. The 90+ litre rated tank I fit with the 90% tank mod will usually take 85 litres at the LPG forecourt pump, which is far better than fitting (say) a 75 litre tank that only fills to 80% so only takes 60 litres at the forecourt. The extra capacity of the tanks that I fit can make for better than an extra 100 miles of range over what the competition fits and even if that range isn't necessary it still makes for less frequent visits to the forecourt to fill up. Also, every time (if ever) an owner runs out of LPG during a journey they resort to running on petrol, so the big tank can help make for better savings than a smaller tank.
