hot water stops heating

Got a Halstead finest gold, the boiler stopped working, it needed a new igniter. Then the hot water stopped coming out hot, so a new diaphragm was fitted. Now the boiler is working & all the rads are getting hot, so is the pump, very hot. When the hot water tap is used (when 1 hot tap is on nothing comes out of any of the other hot taps) after turning it off the boiler shuts off then after a few moments comes back on but only for 20secs. Then it comes on for longer each time it comes back on but by this time the rads have cooled down. fitted a new diaphragm in the Heating side & tried a new thermister but still no change

hi
just seen your question on my halstead post

if you release some of the pressure from the boiler and then see if it re-pressures with the fill tap quickly that is a good clue as to weather the bottom plate heat exchanger is blocked.
pressure gauge should rise quickly in a few seconds if ok

follow the instructions in the manual for procedure if it needs removing.

if you can avoid removing the large chrome pipe running under the heat exchanger and maneuver it out that would help as the 0 rings on the pipe are a difficult size ie my 0 ring box with 500 seals and none the same lol


im not a plumber and you may need a new HE but mine was full of lose bits off black scale.
i rinsed it under the tap and shook it and all the crap cleared and it is fine now (think there is a product for serious scale)

ps if you have a hose lock fitting on an outside tap it fits the hole in the heat exchanger a treet so you can put a good flush through it BOTH WAYS on the 2 black holes.
the other 2 will be clean as there fresh water flow for the hot tap

hope that helps

ok thanks, can't find manual but i'm sure i'll manage

Well i stripped out the heat exchanger found some white stuff partially blocking 1 of the inlets. Cleaned it all out but nothing else came out. Put all back together switched it on & lockout bugger checked everything & 1 of the switches wasn't activating so i undone the nut removed the pin checked it & put it back together again, switched it on & it fired up I started timing it & it went passed the 20second crunch point Then it went off @ 40seconds I waited a while & it came back on again & seemed ok I waited till the house warmed up before i tested to see if the heating came back on after the hot tap had been used. Well it did All seems good now & the house feels hotter, i've had to turn down the heating temp Just 1 thing the pump is still very hot to touch, is this normal for the Halstead finest gold, can someone with this boiler let me know if their's is hot during heating Thanks