Compressed air water draindown adapter for caravans/motorhomes etc. (Truma inlet fitting)

thingiverse

This DIY device is designed to be an affordable alternative to a commercial Truma water drain-down system found in touring caravans or other vehicles. Combined with a modified tire valve and a pair of O-rings, it operates similarly to the Floe device, which costs around 50GBP. This device can be created for less than 5GBP. To use this DIY device, you'll need two rubber O-rings measuring 25mm in inner diameter and 2mm thick, as well as a standard car tire valve. I printed mine using PLA with 0.3mm layers via Slicr/GPX on my Wanhao 4X. The process involves removing the bulbous rubber from the end of the tire valve, leaving only the stem, which is then pushed into the barrel (referring to the 4th picture). Next, slip the two O-rings into their designated seats (illustrated in the 5th picture). The device is then inserted into the water inlet, ensuring it's securely fastened. Note that I didn't need an additional clip, but one has been included for instances where the device might not fit snugly. This clip fits over the tire valve and mates with the original lip under the inlet where the Truma pistol grip typically goes. It can be adjusted up or down as needed to achieve a secure fit.