Our 2017 Benimar Tessoro 481 motorhome came with the new Thetford “blue cap” waste holding tank (for any non-motorhomers reading this – though why would you !?! – Thetford is the company that makes the toilets to be found in the overwhelming majority of European motorhomes. The easiest way to tell which range a toilet belongs to is to look at the colour of the cap on the waste tank – yellow, orange, blue or green). We like to travel around with a spare waste tank, just in case of emergencies. What if we arrive at some really nice French village and want to stay a couple of days but the loo will need emptying tomorrow morning, the service point is out of order and there isn’t another one for miles? These are the unlikely scenarios that keep us awake at night!
So I went online and ordered a spare tank (the freshen-up kits, which include a new tank and tend to be better value than just buying the tank, aren’t available yet in blue cap format) having checked the part number with Thetford (20097706). The tank that arrived was (cunningly) very slightly different to the original. Spot the difference anyone?
Yep, the vent in the top right corner is different, which means that the spare tank wouldn’t slide into the housing built into the van. Hmmm. Luckily you can easily remove the vents, and swapping the vent from our original tank to the new tank confirmed that the tank was fine, all we needed was the right vent for it.
The “right” vent (left) and the “wrong” vent (right):
After a couple of emails to Thetford, we were given a part number for the vent we needed (2378806) and told we could order one from Leisure Spares. This was news to the lady I spoke to at Leisure Spares (her computer said “uh-oh”), but she did very helpfully explain that the last two digits of a Thetford product code normally just specify the colour. She could find the right part in her computer, just not in the right colour (the colour we’ve ended up with looks to me like the pale grey shade of the old yellow-top tanks). As trotting round camp sites / aires with a loo cassette isn’t exactly a fashion parade, I decided that would do nicely!
So you can still spot the difference between the two tanks, but at least now it’s only a cosmetic difference rather than a functional one!
I’ve no idea how widespread an issue this might be. Have we got an early version of a new product, so will always be in a minority of vans with a different vent set-up? Or is the situation more widespread? If so, I’m sure that as the blue-cap tanks become more widely used and others come across the same issue, suppliers will start pointing out the vent question when you buy a replacement tank. For now, though, if you have a blue-cap tank like ours and are thinking of buying a second tank, it could be worth checking if, like us, you also need to order a vent to go with it…..