to flush or not to flush that is the question

[Drfeelgood1]

hello to all with knowledge, its the weekend and i have time to attack the heating system. i am stiil sat with my head in my hands and typing this[ talent]with three red hot radiatiors and nine stone cold ones.
i have taken the good advice of various people and checked TRV pins, bled radiators to the point of feeling i was on the set of Das Boat[ a very leaky submarine] bled the pump,
the system is a vented one and the grant oil boiler 90-120 euroflame is now tripping out . no matter what i do including throttling the rad valves down i just cant get any hot water futher than number three rad, our bedroom is fine but i feel it wont be long before the kids are taken off us at this rate.
am i in the postion of calling for proffesional help?
should i try flushing by draining down and then i presume using a cleaning additive ?
can i hire a kamco pump to try and get rid of a possible blockage? i have been quoted £500 for this service
should shouting at the wall help?
i live near york and make nice tea, help

cheers

Stu

 

[electronicsuk]

Are you sure the system pump is working properly? If the boiler is tripping out (presumably on high temp?) then there may be insufficient flow, and if the problem started suddenly without you making any changes to the system, it's hardly likely that it's going to be curable by a powerflush. If the radiators getting hot are close to the boiler, it might just be due to gravity circulation.

 

[bengasman]

No point in hiring a flushing machine if you don't know how to use it.
Several things you can do first.
Check the pump as described in faq

Turn heating and dhw off.
Find the bypass (probably there, though not always) and close completely
Turn all the lockshields on the cold rads fully open as well as the wheelheads or trv, set the boiler stat about halfway up to max, turn 2 of the warm rads completely off and the last warm rad fully closed and then one turn back open.
Now turn only ch on and see if the last warm rad starts to get warm; if it does leave the valve as is, if it doesn't warm up, turn the valve another half turn and wait a few minutes and check again.
It only should be just far enough open to get the rad a bit warm.
Now check the other rads and close each one that gets warm.
If you can get most of the rads to do something this way, you have a good chance to solve the problem with a chemical flush.

Another thing you can try is to do a "mains"flush as in FAQ, but make sure the expansion tank is isolated and the vent pipe closed with a stop.

 

[JohnD]

have you balanced it yet?

start by turning off the hot ones and see if the cold ones warm up.

Have you done anything to it recently?

If you bleed the highest radiator in the house, does water squirt out forcefully? What colour is it?

When you look in the Feed & Exoansion tank in the loft, how much water is in it? What colour? Is there mud at the bottom? How old is your system and how has it been maintained?

 

[Drfeelgood1]

have you balanced it yet?

start by turning off the hot ones and see if the cold ones warm up.

Have you done anything to it recently?

If you bleed the highest radiator in the house, does water squirt out forcefully? What colour is it?

When you look in the Feed & Exoansion tank in the loft, how much water is in it? What colour? Is there mud at the bottom? How old is your system and how has it been maintained?

hello, cheers for your advice, when the fault showed it self i followed the advice of trying to balnce the sysytem by throttling the valves that are not the TRV's down in attempt to get a better force through the pipes to move the airlock or blockage.

no matter what settings i usedi could not get any heat beyond what i presume are the first three rads in the sysytem from the boiler, they are read hot when the system is turned on.

the expansion tank has clean water in it, i am not sure of the depth , is this critical? the system is in the main eight years old and as we exytended the house was added to a much older sysytem the installation date of which i do not know.

to this point the sysytem has not had any maitanence on it.
follwing the advice of the plumber who installed the new section i have tried to drain the system down as he feels its an air lock thats preventing full circulaton or a lazy pump, but the pump does work on all three speeds.

an intresting point is that the upstirs rads have all emptied ok but the downstairs ones with out an actual drain vlave directly beneath them will not empty, the other downstirs rads will stiil spurt clean water out when the bleed valve is opened, one of the rads that has empitied downstairs had dirty black water in it.

cheers again for all help and advice

stu

 

[JohnD]

If you bleed the highest radiator in the house, does water squirt out forcefully? What colour is it?

this is an important question.

 

[Drfeelgood1]

If you bleed the highest radiator in the house, does water squirt out forcefully? What colour is it?

this is an important question.

Hello, when i have bled all the top rads in the house which are all on the same level the water was allways clear

cheers

Stu

 

[Drfeelgood1]

If you bleed the highest radiator in the house, does water squirt out forcefully? What colour is it?

this is an important question.

Hello, when i have bled all the top rads in the house which are all on the same level the water was allways clear and it didi come out forcefully, my only concern was with one rad when trying to blead it one time it was atking ages for any water to appear and i began to think that it was actually drawing air in?

cheers

Stu

 

[JohnD]

my only concern was with one rad when trying to bleed it one time it was taking ages for any water to appear and i began to think that it was actually drawing air in

was this the highest rad in the house?

Try that one. It's important.

 

[Drfeelgood1]

my only concern was with one rad when trying to bleed it one time it was taking ages for any water to appear and i began to think that it was actually drawing air in

was this the highest rad in the house?

Try that one. It's important.

hello, i tried the highest rad in the house and it bled up fine with clear water coining out, its one of the three rads that gets very hot

cheers

stu

 

[JohnD]

OK. If water is coming forcefully out of the highest rad, then you have probably not got a blockage in the Feed & Expansion pipe.

No reason why you shouldn't have a go at DIY fixing; it may save you the expense of a professional, and will in any case not do any harm if you have to call one in later.

You say some rads are hot and some are cold.

Completely turn off all of the hot rads, and all of the cold except one. Open the valves at both ends (you may need a small spanner to open the lockshield valve) The boiler need not be set very high. Check that the pump is set to high speed. Does this single open rad get hot? If so, you have at least got flow. If not, does it have a Thermostatic Radiator Valve? It might be jammed shut.

Repeat this "all off except one" on all the other cold rads and report back what you find.

Feel the Flow and Return pipes at the boiler, and see how hot the return pipe is. It should be pretty hot, like the one radiator, if there is flow. Feel the pump. It should be about as hot as the pipes. If it is hotter, it is jammed.

If you have some flow, you can at least use a sediment-loosening chemical cleaner like Sentinel X400. I am not a pro and I use this because it is not aggressive or acidic like faster cleaners. You leave it circulating for 4 weeks. You know it is starting to work when the circulating water goes jet black with loosened sediment. Can you do basic DIY plumbing? If so, consider fitting a Magnaclean on a 22mm vertical return pipe. It will cost about £100. As you say parts of your heating system are old, it is likely to have a lot of old sediment in it, and I guarantee you will be amazed and delighted to see how much sediment the Magnaclean traps.

However a chemical clean will not clear a completely blocked pipe, since it can't get down the blocked pipe to reach it.

Also, have a look round all the visible pipes, especially around the boiler, cylinder, pump and 3-port valve and see if you can find a bypass. This bleeds off flow between the Flow and the Return pipes, and may have a valve on it that you can adjust. Sometimes they are hidden under the floor.

You mentioned that some of the downstairs rads will not empty. This is probably because they are on drop loops fed from above, i.e. the pipes to the radiators do not go downwards into the floor. You can drain them by loosening the connections from the rad valves into the rad. It will gush or leak out so empty everything else first, and have plenty of bowls and trays ready, as well as an assistant to empty them. Black radiator water leaves a permanent stain. If you can take up a floorboard some people just let it run out under the floor. Once drained, you can fit a Lockshield Valve with Drain-off which only costs a few pounds,, to each of these radiators. You can put a drain hose on it when necessary.

Post photos of the pipes around the pump, boiler, cylinder, 3-port valve if you can. This may give clues.

You mention that the system has been extended. I hope it has worked correctly in the past since this was done? If not, it might be a design or installation error rather than sediment or a fault.

 

[Legion]

Change pump.

 

[glasgowgas]

Change pump.

legion, have you had replies to posts deleted tonight??

 

[Legion]

legion, have you had replies to posts deleted tonight??

Yep, so what`s new? Hope you get this one ..I feel an insult coming on....

 

[bengasman]

Bit hard to insult a troll whose standards are lower than a hunkering worm