Tony replied to Andrew's plea with: > > "Normal" antifreeze should be changed every two years (so the makers > say)but I expect it will do for longer - they will be covering their > backs. > > You can buy 5 year antifreeze but you must work out any cxost > advantage - its dearer. > > Never run at more than a 50% mixture or below about 20%. I starts > with 50% (easy to get by filling pint of antifreeze - pint of water) > sp you can thgen top up with water without risking overdiluting the > antifreeze for a while. > > Ideally both the engien/skin tank and teh central heating would be > flushed using a hose and "blowing" the water throuigh the > systems "backwards". This is likley to be messy on the engine - may > require the thermostat to be removed) and virtually impossible on the > central heating. Best flush throug from the fillers to the best of > your ability. > > I hope that the central heating has a header tank and not a prerssure > vessel (accumulator) otherwise you need a pump to re-presurise the > accumulator system with the 50% antifreeze mixture. > > I also hope the installer has fitted a drain cock and hose connection > at the lowest point! If this is a narrowboat I expect you will need > to pump the old liquid out to avoid spiling the flooring. I find a > drill pump adequate for this because it is being fed by gravity for > much of the process. Make sure the hoses are cliped in place to avoid > drips. > > Ideally you wopudl mix the antifreeze and water before refilling the > central haeting system, but at this time you will not know teh > capacity, so fill pini & pint about, but it may take a week or so to > get the total radiator surfaces hot. Bleed the radiators as per > normal domestic ones, but if this is an accumulator system make sure > you repressurise it as required.
Yep, spot on, can't add anything to that. As far as mixing antifreezes is concerned I think that the non- compatible type is more expensive (probably the 5 year type, as mentioned by Tony). If you go for one that contains Ethylene Glycol you should be OK (and this will be the type that most motorist's centres will sell). Be prepared to use much more than you think you will. From memory, doing both the central heating and engine on Albion, on the one pint AF, one pint water basis, as described by Tony, it took 20 litres for the resultant 50/50 mix. If you are still unsure I will help at the Blue Lias. Yes, I know, Mr Keens I still haven't sent my booking in yet. I intend to do it today(ish) ;-)) Roger
