|
Home > Archive > Plumbing forum > June 2005 > Central Heating Problem
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
Central Heating Problem
|
|
|
| Hi,
I'm new to this group, and I notice there aren't many postings, but I
hope someone can please offer advice. I'm not very good with plumbing,
so if I am lacking info, please forgive me and ask for more details.
Anyway, My central heating pipes/rads make quite a lot of noise of
running water, particular upstairs and in the pipes going to upstairs.
The radiators upstairs are a nightmare. One of them is relatively ok,
heat-wise, but it needs bleeding every 2 or 3 days. The other radiators
are cold and appear to be empty. If I open the bleed valves on these
with the thermostat set so the pump and heating is running, then water
drains from the radiator (I can feel suction on the bleed valve.) If I
turn the thermostat so the heating is off, the radiators fill up, but
when they are full, they are still cold (getting full with cold water??)
Sometimes, through bleeding all rads at the same time and then switcing
the bleed valves off, I hear running water, then the header tank
overflow pipe starts spilling water. And that's about it, I'm not sure
where to begin to look.
Does anyone have any ideas or suggestions. I'm quite prepared to call a
plumber out if that's what's necessary, but I'd prefer to know what the
problem is before I did that so he can't try pulling the wool.
Many thanks for reading,
Bob
| |
|
| hi there.
i think it is big hole in your pipework somewere, under the floor.
lot of destruction is comming - you must lift some wood on groundfloor and
look for big lakes under.
that can be some old pipe joint or compresion fitting.
rob
| |
| tam the plumber 2005-06-16, 2:28 pm |
| It sounds like your heating system is an old one. It is possibly drawing air
( in through the expansion pipe ) or more likely, very old and making
hydrogen gas through corrosion. It also sounds like the pump is on the
return. That means your system is operating on a negative pressure whereby
the pump is pulling the water around the system instead of pushing it (too
hard to explain without getting technical, but its to do with how it's
piped) That is why when you try to bleed the rads with the pump on it pulls
air in through the air vent. Don't bleed radiators with the pump on!
Rads not heating prob due to sludge in pipework (due to corrosion). A
powerflush (not cheap around £300-£400, and not a DIY thing really ) would
solve the problem of the sludge and a corrosion inhibitor will stop further
sludge formation. A sludge remover (Fernox X400) might work on its own
depending on how bad it is, followed by X100 inhibitor.
When you bleed the rads the water comes from the header tank, hence the tank
filling. The overflow runs because the ball valve is jamming or needs
rewashered.
If the system is really old think about changing it to a shiny new
condensing boiler system. Heating systems (much to some peoples surprise) do
not last forever.
Tam
|
|
|
|
|