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As part of an ongoing attempt to generally improve what i think is an 8-year old Baxi 105e ( i inherited it with house ), i want to fit a new magnetic descaler of the type shown in the photo. (in case the photo doesn't upload the descaler is a 'LIFF Shortest' barrel type.)
I'd like to check about shutting off water-flows - will it be dryish in the area of the job if i - a) shut down the main cold water stopcock to stop flow from the left of the unit; and b) on the right side in the photo, close the isolation valve on the cold main supply into the boiler to stop water coming back down from the DHW section of the boiler ?

A small separate query : i can see an earth spade on the side of the gas valve and i see it in some illustrations of the 105 Baxi, but i don't think i have ever seen an earth lead attached to that point on this one - the boiler runs fine after the main heat exchanger was changed recently ( kettling causing complete shutdown ), so is that earth lead not needed on some models ?

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thanks for posting.
i stopped fitting those boilers about 10/11 years ago when the duotec took over. there is a date on the data badge so take it at around 08.
there is normally an earth strap to the left side of gas valve connecting to the tab located at the hole in the cabinet left side of the gas stem.
do you need it? -no idea :)

why dont you fit a cigar shaped in-line filter? there a lot neater and i have not seen that type before!
if you turn off mains-rooster and open hot and cold tapes it will drain off if you have an outlet lower than the scale filter.

there will still be some in the pipes and filter anyhow so expect some to come out. this is why a wet vac is favoured by many. either way a towel works and wont be more than a couple of pints.

i repaired one with the same faults in january, needed a new plate heat exchanger and was kettling due to the by-pass being blocked (reaching 80-90 on the led's fast then clanging pooor hot flow)!!

hope that helps and remember... water spills dry faster in warm weather ;)

as regards to merging posts its a lot more confusing than it looks.....sod it :lol:
Thanks Redshaw - yeah point taken about the narrower filters, i'm just taking the simple route as there is already one of those LIFF jobbies in place as seen in the photo. Got hold of one for a mere 14 squids. Yep - towels in good supply as per usual whenever i approach the utility-room with a spanner in hand! That earth terminal is on the right side of my gas valve looking from the front obviously, and i don't think it's ever had a lead on it even though the 105e manual shows one...weird. The plate/ hot water heat exchanger is next on my list as although everything is working reasonably ok i'm not impressed by the rate of flow from the hot taps and wouldn't be surprised if the plates are half-blocked but not enough to cause over-heating. My leds shot up as you describe but that was fixed with a recon main heat exchanger (what a b'strd they are to get off!) On the theme of getting to the plate exchanger - is it a fairly routine move to remove the left-hand side panel to improve access ? I can see that there are a few screws on the front & back edges, and then a locating tab to push up and away from ?

Many thanks.
i cant and wont promote unregistered boiler repairs so i wont be liable for that advice!

the plate is a right bstard but might help taken from the right other than that half the innards out to remove and that includes the gas valve and new seald and about 4 hours.
Cheapo gate valves....

I thought it looked great especially when I closed[…]