cold feed problem

[monster]

hi.
have a prob with the cold water feed form the loft to the boiler.we took of a rad to tile behind.after putting it back on. the boiler making a woshing sound,rads down stairs are fine.up stairs hot at bottom cold at top.
manweb engineer came out and has said the cold feed from the loft to the bolier is blocked. quoted £600 to do it
now he has said that it could be fixed if we back filled from the overflow vent pipe that is the same tank in the loft.he said it is just a case of pouring water down slowly while someone bleeds the radiator.he said it wouldnt cure the blockage but would stop the noise.
would this be a solution in the short term to getting the system working again and is it easy to do???????????
any help would be gratfully recieved

 

[oilman]

No it wouldn't be a short term solution. It's potentially dangerous as you have no water supply if the boiler overheated. (Dont rely on safety stats, everything can fail when you need it most).

You need to clear the blockage, and you will probably have to cut the pipe, if you can't do it, and you dont live too far away I'll do it for half BGs quote and I'll be quite comfortable :

To find the problem find where the feed pipe joins the system, it will be within a foot of that going up towards the tank.

 

[monster]

No it wouldn't be a short term solution. It's potentially dangerous as you have no water supply if the boiler overheated. (Dont rely on safety stats, everything can fail when you need it most).

You need to clear the blockage, and you will probably have to cut the pipe, if you can't do it, and you dont live too far away I'll do it for half BGs quote and I'll be quite comfortable :

To find the problem find where the feed pipe joins the system, it will be within a foot of that going up towards the tank.

lol cheers for the reply
spoke to me dad,its his house
apparently the quote was for power flushing the entire system,and for altering the tank in the loft. to put the vent pipe inside the bottom of the cold feed tank.not sure why?????lol
dad said he wouldnt just try and unblock the colde feed pipe.would have to power flush the whole system.
but he told us that it didnt need flushing as he can say for sure that the block is in the cold feed pipe.
he checked the pipe from the airing cupboard up th the loft,by turning off the red handled valve and disconecting the pipe below it.water was coming from the loft so he said it was definatly below the valve in the airing cupboard to where it joins the system.which is about 15ft of pipe
6ft of which is vertical.
so if you say it would be about a foot away from the system then it would be under the floor boards on the landing.
wot annyed me was the engineer said it didnt need flushing,but that is BG `s policy of doing it.

 

[peter anderson]

Couldn't the problem of radiators which are hot at the bottom and cold at the top and noise in the system be solved by venting(bleeding) the radiators? Is the whooshing sound made by the boiler that leads you to think that there is a blockage in the cold feed pipe oilman?

 

[oilman]

Most systems don't need flushing most of the time, but the poor guy gets beaten up and forced to take part in their advertisements if he doesn't get enough powerflushes in a month. There's probably some sour grapes since BG had to climb down from their attempt to copyright the word "powerflush" and its derivatives.

 

[monster]

Couldn't the problem of radiators which are hot at the bottom and cold at the top and noise in the system be solved by venting(bleeding) the radiators? Is the whooshing sound made by the boiler that leads you to think that there is a blockage in the cold feed pipe oilman?

hi
the BG who looked at the system said the cold feed is def blocked definatly blocked.we have
tried bleeding all the rads. no pressure in the ones up stairs.
the prob is........soon as you turn the system on the it starts making this loud whoosing noise just above the pump.it stops after a minute.
the rads down stairs all get hot. and you can bleed them water comes out instantly.upstairs rads get hot 3/4 hot from the bottom. soon as you open the bleed on the first or last rad in the system the whoosing starts
no water or air comes out the first one. some comes out eventually from the last one but no water or air comes out of the others upstairs.
engineer said that cos the water has been drained from one rad that was taken off.the cold feed isnt replacing it.cos its blocked.

 

[AlanE]

I have a nice powerflushing machine and I am happy to use it in those situations where I consider it will give a benifit for the cost of the process.

I also take water sample before a flush to confirm it is required.

BUT I can assure you that it would be a sheer fluke if it solved your problem!

Powerflushing works by pumping a chemical around the system. Note around the system it cannot remove a total blockage. Provided there is a path for water flow, with the right chemicals, a vast improvement can be made.

You say you have a total blockage in the cold feed so powerflushing would be a total waste of time. Other methods need to be used.

Alan

 

[monster]

I have a nice powerflushing machine and I am happy to use it in those situations where I consider it will give a benifit for the cost of the process.

I also take water sample before a flush to confirm it is required.

BUT I can assure you that it would be a sheer fluke if it solved your problem!

Powerflushing works by pumping a chemical around the system. Note around the system it cannot remove a total blockage. Provided there is a path for water flow, with the right chemicals, a vast improvement can be made.

You say you have a total blockage in the cold feed so powerflushing would be a total waste of time. Other methods need to be used.

Alan

hi
well acording to the BG chappy its completly blocked.
the heating system worked perfeclty fine before dad took the rad off.
it was only off for 2 days. going by wot my dad said ,he turned the valve ontop of the boiler that isolate the rads. the turned the nob on the rad that controls the heat. then took the rad off.didnt drain the system just that one rad.so i cant understand how in 2days the pipe can get completly blocked.

 

[breezer]

its only a thought, are you thinking of blockage as in getting smaller and smaller, until blocked?

it may be an obstruction that is causing the blockage.

we had probs with our c/h turned out pump impellar was all smashed (bg man showed me) question is what got in there to be able to break impellar, it may have been something that was always there, but got diss logged, may be similar in your case?

 

[monster]

its only a thought, are you thinking of blockage as in getting smaller and smaller, until blocked?

it may be an obstruction that is causing the blockage.

we had probs with our c/h turned out pump impellar was all smashed (bg man showed me) question is what got in there to be able to break impellar, it may have been something that was always there, but got diss logged, may be similar in your case?

i think its going to be sludge or rust if its complelty blocked.
the pump is fine.
the noise is coming further up from the pump. its a rythmic sloshing.whooshing noise.you can definatly here water sloshing.

 

[AlanE]

It didn't block in two days. It's been blocked for some time its just that when you removed the radiator you also removed a quantity of water from the system so when you replaced it the water that was left was insufficient to run system properly.

The cold feed blockage is a COMMON problem and is due to 'funny' currents set up within the pipe where it joins the heating system. There are methods that can be used to dislodge this but for the DIYer it is easier to drain the system, remove a length of feed pipe about foot long close to its junction with the heating system.

If the blockage is not actually in the cutout length it will normally be pretty close.

Alan

 

[COG]

As previously said a blocked pipe can only be cleared manually by replacing the section or gaining access and rodding it out, its generally within reach of the boiler inlet often gathered in a compression joint. Best to remove as much water from the system as poss shut off the water and power and clear away anything that could get wet and undo the return connection, simple coat hanger or curtain wire will often remove the obstruction but when it does clear make sure you have an extra pair of hands and a mop.