Tony Brooks

Yes, but if you don't want to display ignorance it is best to use the proper word. That is all.

Fair enough, I did not find undoing those screws either difficult or boring, I thought there were only about eight.

Hence, me saying put the cover back on the spyhole. I found out the hard way and singed my eyelashes. Personally I would take the burner out to do the job properly, but the GSIUR means a live-aboard needs a gas Safe registered person so we really should not advise that.

Sorry Mike, the Alde 292x series do, I had a latish 2928 model, and it had a pilot light, unlike the 3000 series. that is one reason they tend to be a bit hungry on the gas. The pilot light flame is asymmetric with a sort of offshoot going off to play on the probe. When fluff etc gets into the pilot light burner it tends to not heat the probe enough or not at all. They also use the ionisation in the flame playing on the flame failure probe to shut the igniter down. If the pilot light goes out, the igniter start to work to reignite it. If you run out of gas or turn the bottles off without turning the boiler off or turning the master switch off it plays havoc with the igniter and, given time, the batteries. You push the control knob down to bypass the pilot flame failure with the knob in the "spark" position. Then you keep it held down until the clicking stops, or you hear the main burner ignite. At that point you set the control to the temperature (gas flow?) you want. It is an electronic igniter. Apart from the electronic igniter they are all very much old school.

The "walls all the way across" are called bulkheads, as are any other "wall" across the boat.

Together with the domestic load. @Steve Manc With LA batteries for any given load the discharge will be less as a proportion of battery capacity and the less it is, the slightly better capacity the batteries have. I suppose they may have configured the charging as one alternator charging one bank plus engine battery and the other alternator charging the other bank. Be aware that with LA batteries they will lose capacity over time so the older they are OR the less well charged you keep them, the faster they will discharge.

Just like computers, which it kind of is, a power down, long pause sometimes lets them re-boot from their ROM (or whatever). If you powered down for several minutes I doubt overnight would make much difference. Absolutely no help, but now you know why I prefer hard-wired and switched systems, may be less convenient and less "flash", but far easier to diagnose with simple equipment. I had hoped @nicknorman would chip in, at least with some advice, him being one of our electronics experts, so still hoping. I don't know too much abut the system, but I presume it has a master unit, and if one channel has failed I would be looking at connexions. If one channel refers to a "slave" unit then that could be suspect.

Have you tried totally de-powering the whole bus system, leaving it off overnight and then repowering it? Maybe a long shot but worth a try.

and a charged domestic one will probably do if it is lead acid.

So true.

Which is why I asked if he ha cleaned the battery terminals and clamps.

I would suggest that it is just as likely to be the pilot light burner "fluffed/spidered up" so it no longer plays upon the flame failure probe. It is fairly easy to disconnect the gas pipe, undo a ret of screws holding the rectangular burner mounting plate to the boiler case, then it will just pull/lift out so you can give the whole thing a good clean up. Only do this if you are NOT a live aboard and if you are competent to remake the gas pipe joint. Otherwise, I used to have to solve it almost every year. You can see the pilot flame through the little circular window low down in the case. If you loosen the three little screws and remove two the "window" will swing down, so you can use a compressed air duster with the directing tube fitted t blow the pilot burner free of muck. Make sure you replace the little disk before trying to relight. You may need a couple of attempts at cleaning it. Alde no longer supply parts for those boilers.

It looks like a very old PRM Hydraulic. I can't tell which one because the photos have too much obscuring the box. PRM normally fit a number plate, so have good clean off and look round it. You did not ask, but it uses engine oil, say SAE 20W50 or 15W40