Q NO HOT WATER We can’t get any hot water, despite running the engine for two hours. There is no split in the calorifier but it doesn’t give hot water to the taps. I have replaced the water pump because the overall water pressure was poor. This has not really improved, but are the issues linked? Any ideas? LEARYD, via the CB website
A TONY REPLIES: The domestic water pump might give low pressure but as long as water is flowing from the hot taps it will not effect the ability of the system to provide hot water. Unless there is a valve that needs turning on, the engine fan belt is loose/missing, the engine thermostat is stuck open, or the engine cooling system header tank is very low on coolant, then the most likely problem is an airlock in that part of the cooling system that feeds the calorifier coil.
There are two way to tackle this. As long as the pipe runs are sensible with no upward loops and the coolant header tank is higher than the top calorifier coil connection, the easiest is to locate the feed and return pipes between engine and calorifier and find the highest joint. While keeping the header tank full of a 25% to 50% antifreeze mixture, loosen and manipulate the joint until any air in the pipes exits and coolant starts to weep out. Tighten the joint and test. If that does not work try it again with the engine running at about 1200rpm.
For the second method, get a can of coolant mixture and a friend ready to top up the header tank as required. Identify and loosen the hose joint where the return from the calorifier coil connects to the engine. Start and rev the engine as above and pull the hose off the joint but put your thumb over the connection on the engine side so no coolant leaves the engine. Water should gush out of the hose but there may well be air in the pipes so wait 30 seconds or so to be sure no more air is coming out of the hose. Refit the hose, tighten and test.
Some engines have a separate thermostat controlling the calorifier circuit. In this case a thermostat jammed closed would prevent the calorifier getting hot.
If the Pressure Relief Valve (PRV) that is usually close to the calorifier on the hot domestic water outlet is leaking badly, domestic water pressure would be reduced and the water in the calorifier would leak away before it got hot – but the domestic water pump would run very frequently or all the time. Q FITTING SOLAR PANELS I’m taking ownership of a widebeam which will eventually become my permanent residence. I want to have solar panels installed to keep the batteries charged while I’m out of the country, but when living aboard I want them to cope with the usual liveaboard appliances. Can you recommend a company to fit the solar equipment? CHIANTI, via the CB website
A TONY REPLIES: I don’t recommend companies unless I have used one myself, but I would suggest that you look in publications such as this or search online. Also, ask fellow boaters for personal recommendations – but be aware that many will have fitted panels themselves.
While a single 60 to 100W panel will keep the batteries charged, to cover your electrical needs in the winter will require far, far more and even then may not be sufficient during long dull periods. At least with a widebeam you have more roof space. It might be more cost-effective to accept that you will have to run the engine every day or so at some points during the winter and fit fewer panels.
Also, install an ammeter and SmartGauge so you can monitor your batteries properly and know when solar charging has not been sufficient, to avoid ruining your batteries. WHO RULES OVER FUEL SPLIT? Q Can a supplier of diesel dictate the split between domestic and propulsion (for fuel duty purposes)? Also will this split end when we leave the EU? STUART&VIV, via the CB website A TONY REPLIES: The situation is not clear-cut. HM Revenue & Customs are clear that it is up to the boater to declare the split, and all the seller has to do is to record it and identify their boater. However, the price you may see at a supplier is technically only an ‘offer to treat’ (which means to negotiate), so if the seller will only sell with a given split then it is a contractual matter between you and them: either accept the terms of their contract or go elsewhere.
On the second point I think the only answer at the moment is ‘who knows?’ I suspect that if and when we do eventually leave the EU, rescinding the present arrangements will be way down any government’s list. In my view a future government outside the EU might be so strapped for cash that we end up paying road diesel prices anyway.
You can bleed air from the pipes