Failing TRUMA water pump?

From reading your story, the pump is working and when you run it when it is not connected to the caravan socket it works fine pumping water. So the fault is in the caravan connection in.  I would first of all look at the 'O' rings, then the regulator, your caravan hand book should tell you where it is and how to adjust.  There may be an air lock in the system.  If you want to get a replacement pump they are widely available all over Europe so if the is a caravan dealer near you they should have both rings and pump.  I have had perished  'O' rings in the past and have had to adjust the pressure:  I now carry a spare pump and 'O' rings just in case.  I 'lubricate' the 'O' with a little butter/marg  (silicone spray/grease  is also fine) every so often and have not had any problems with them for years.

Enjoy the rugby; it has been very exciting!

I would also advise replacing the Truma pump with a Whale High Flow (with Truma fitting) - readily available from accessory shops and on line. The pressure and flow rate are much better plus the blue pipe is more flexible than the Truma one.  It was the first thing I did when we got our 'new' van. 

Thanks for the response. But it cannot be an airlock anywhere, as I have disconnected everything except a couple of inches of pipe inside the caravan (ie before the pressure switch so it can’t be anything to do with that either). Thus there is no where for an airlock to form. Hence, it must be either the fitting itself or the pump.

I’ve now spoken to a service depot in UK, and they think the pump is running below par, but I cannot check that here easily.

just booked in to a site in Lyon, and only 5 nights left on one-night stopovers, and the next one should be mains water, so that will be a test with greater pressure.

Getting a replacement pump is one thing, but I’d have the challenge of fitting it to the Truma connector in a waterproof manner, which may not be simple.

The forthcoming semifinal will take my mind off the issue!

Our recent experience of a cracked Truma water inlet housing while in France was contrary to the advice that spares are widely available. Several dealers looked baffled by a photograph. Internet searches revealed nothing.  A direct contact with Truma UK didn’t reveal any French outlets. Jackson’s Leisure UK advertise posting abroad but wouldn’t when we asked them to. A spare was delivered within 24 hours of our return. Part of the reason for problems in France might be that European travellers make far more use of on site facilities than us Brits. Motorhomes (camping cars) are plentiful with underslung tanks and much smaller, onboard water tanks to be filled with a watering can, are popular with Dutch travellers.