Sorry for confusion, will teach me to multitask..... 
Need help with a hot water problem
- Thread starter thebaronn
- Start date
Hi gigz, I'll take a better photo, two mins. Is getting the coil out a relatively easy task? I thought they were sort of part of the cylinder. No worries about the mixup Hugh, I have at least learnt something (B is for Bath, love it) 
He meant poke it out in situ DO NOT attempt to remove coil it aint gonna happen! Its a case of turning water off draining system and cracking the nut on cyl port b goes to and the one on the cylinder below it, this is the inlet/outlet of coil, give it a good poke with a bent coat hanger and see what crap you can pull out.
Thought as much, hadn't heard of removing a coil! It's pretty snug in there, might have a job without removing the cylinder. See photo. Is it also possible to perform the same procedure at the top of the coil (return to boiler)?
If I end up needing a new cylinder, will I also need a new immersion, or are they pretty much a standard fit (albeit that this one is probably at least 20 years old)?
If I end up needing a new cylinder, will I also need a new immersion, or are they pretty much a standard fit (albeit that this one is probably at least 20 years old)?
Think you are mistaken where port b goes to cyl is the top of coil. See indirect cyl on this page 2nd one down it will help you understand.
http://www.diydoctor.org.uk/projects/domestic_hot_water_systems.htm
http://www.diydoctor.org.uk/projects/domestic_hot_water_systems.htm
Think you are mistaken where port b goes to cyl is the top of coil. See indirect cyl on this page 2nd one down it will help you understand.
http://www.diydoctor.org.uk/projects/domestic_hot_water_systems.htm
http://www.diydoctor.org.uk/projects/domestic_hot_water_systems.htm
If access is tight then it's probably going to be easier to drain and remove the cylinder. (Will need to drain CH system and cylinder.) May be an advantage though as cylinder can be removed to outside and given a thorough clean out, coil can be tested for flow with a hose and detritus can be removed from the bottom of the cylinder.
Immersions are standard, but maybe as well to fit new, especially if you currently have the older type immersion without an overheat cutout. (If the stat fails in the older immersions then the water can boil, which in turn boils the contents of the cold water storage cistern above. Have been incidents where plastic cisterns full of boiling water from faulty immersions have then collapsed, dumping contents through ceiling, in one case fatally when a child was sleeping below.)
Blockage usually indicate a build up of muck in the system, worth a look at Sentinel X400 for a chemical clean. http://www.sentinel-solutions.net/product/detail/central-heating/liquids/x400-system-restorer/
Immersions are standard, but maybe as well to fit new, especially if you currently have the older type immersion without an overheat cutout. (If the stat fails in the older immersions then the water can boil, which in turn boils the contents of the cold water storage cistern above. Have been incidents where plastic cisterns full of boiling water from faulty immersions have then collapsed, dumping contents through ceiling, in one case fatally when a child was sleeping below.)
Blockage usually indicate a build up of muck in the system, worth a look at Sentinel X400 for a chemical clean. http://www.sentinel-solutions.net/product/detail/central-heating/liquids/x400-system-restorer/
Yes, was a bit puzzled about that bazdaman, just checked out the cylinder and it is just like the indirect one you pointed out in your link. Port B goes to top of coil, return is at bottom.
Can we definitely rule out air lock (because of water coming out of bleed valve)? Can air be shifted with the tank in situ.
Removing the cylinder and cleaning it sounds like the next step. If I had money to throw around I might get a new one, but marriage next year is bleeding me dry so if this can be fixed then that'd be great. Found a date on the cylinder, it's from 1984; IYO is it worth saving?
Immersion has been accidentally left of for prolonged periods whilst we've had no HW from the boiler, but after reading that story Hugh, will definitely make sure it isn't in future.
Hugh, regarding the X400 System Restorer, are you suggesting that I add that with the tank in place? Is the idea that it will bust through the blockage? What would be the best way to add it to the system?
Sorry for all the questions guys, think we're making progress and I am fascinated to learn how all this works!
Can we definitely rule out air lock (because of water coming out of bleed valve)? Can air be shifted with the tank in situ.
Removing the cylinder and cleaning it sounds like the next step. If I had money to throw around I might get a new one, but marriage next year is bleeding me dry so if this can be fixed then that'd be great. Found a date on the cylinder, it's from 1984; IYO is it worth saving?
Immersion has been accidentally left of for prolonged periods whilst we've had no HW from the boiler, but after reading that story Hugh, will definitely make sure it isn't in future.
Hugh, regarding the X400 System Restorer, are you suggesting that I add that with the tank in place? Is the idea that it will bust through the blockage? What would be the best way to add it to the system?
Sorry for all the questions guys, think we're making progress and I am fascinated to learn how all this works!
Drain a bit of water off, add chemical to F&E cistern, then allow to refill so chemical is drawn into system, or if draining completely tip it into F&E cistern as its refilling. Sentinel do say though X800 'will not clear a completely blocked pipe', up to you if you wanted to try. I wouldnt leave it in too long though, unlike X400.
More info: http://www.sentinel-solutions.net/product/listing/central-heating/liquids/
More info: http://www.sentinel-solutions.net/product/listing/central-heating/liquids/
Hi guys, sorry for the delay, work has a habit of getting in the way of house problems! My concern with X800 would be that it would expose weak points in my aging system, and I may end up springing leaks. Is this a possibility?
Fearing that it is clogged, it sounds like the best/cheapest thing to try in the first instance is to run some X400 through it, to see if that shifts anything.
This may be a silly question, but where is the best place to drain some water off before I add this to the system? Any of the rads? There is space to add the solution to the F&E tank without draining any off first, can I do it this way around i.e. Add fluid to F&E tank, drain water off from rad, fluid drawn down into system? Cheers.
Fearing that it is clogged, it sounds like the best/cheapest thing to try in the first instance is to run some X400 through it, to see if that shifts anything.
This may be a silly question, but where is the best place to drain some water off before I add this to the system? Any of the rads? There is space to add the solution to the F&E tank without draining any off first, can I do it this way around i.e. Add fluid to F&E tank, drain water off from rad, fluid drawn down into system? Cheers.
Baron, just before you start taking out tanks, are you 100% sure the pmp is running when you select hot water only?
I am surprised others don't seem to be saying this but this is what I would be doing:-
To chemically clean to try to solve a blocked heating coil:-
Close one valve on EACH rad!
The add X800 to the heating water and have a shower so that the cylinder tries to reheat. Turn the cylinder stat up to max to keep boiler on!
Doing that will concentrate the X800 in the heating coil and not waste it in the rads!
Run it on HW for 2-4 hours and HOPEFULLY you might see an improvement in the flow!
You can in effect measure the flow by seeing how the heat coil RETURN temp compares with the flow.
When ( if lucky ) the cylinder is heating up nicely and the return is also hot THEN open the rads and run the heating for and hour so the X800 can clean them out.
Then drain and refill with inhibitor like X100.
Tony Glazier
I am surprised others don't seem to be saying this but this is what I would be doing:-
To chemically clean to try to solve a blocked heating coil:-
Close one valve on EACH rad!
The add X800 to the heating water and have a shower so that the cylinder tries to reheat. Turn the cylinder stat up to max to keep boiler on!
Doing that will concentrate the X800 in the heating coil and not waste it in the rads!
Run it on HW for 2-4 hours and HOPEFULLY you might see an improvement in the flow!
You can in effect measure the flow by seeing how the heat coil RETURN temp compares with the flow.
When ( if lucky ) the cylinder is heating up nicely and the return is also hot THEN open the rads and run the heating for and hour so the X800 can clean them out.
Then drain and refill with inhibitor like X100.
Tony Glazier
Hi Tony, thanks for chipping in, appreciate it. I can definitely hear the pump going with HW only mode. See earlier in the thread, the boiler will not stay on when in HW only mode, it cuts out in <1min, if it comes on at all. Even with the stat on full / taken away from the cylinder. No problem with CH, all rads heat up. Presume boiler is cutting out as there is not enough flow in the HW loop e.g. blockage?
Any suggestions regarding my last comments?
Any suggestions regarding my last comments?
RE adding X400, found JohnD's post in this thread useful:-
http://www.diynot.com/forums/viewtopic.php?t=264272
Will pick some up this week. Fingers crossed it works!
http://www.diynot.com/forums/viewtopic.php?t=264272
Will pick some up this week. Fingers crossed it works!
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