Help please for a rookie!!

I have a sealed pressurized heating system running off an oil-fired
burner. For some time now there has been a loss of pressure in the hot
water taps, to the point now where if one tap is on nothing will come
out of any other tap. The cold water is fine. When it was first
installed five years ago the hot water was the same pressure as the
cold.
I remember vaguely having a problem with a leak coming from the top of
my hot tank a couple of years ago from a little red knob which was
loose. I tightened this down, which i'm not sure I should have as it
looks like some sort of pressure relief blow-off.
Any help would be greatly appreciated

On 2006-09-23 11:48:11 +0100, "al" said:

Help please for a rookie!!

I have a sealed pressurized heating system running off an oil-fired
burner. For some time now there has been a loss of pressure in the hot
water taps, to the point now where if one tap is on nothing will come
out of any other tap. The cold water is fine. When it was first
installed five years ago the hot water was the same pressure as the
cold.
I remember vaguely having a problem with a leak coming from the top of
my hot tank a couple of years ago from a little red knob which was
loose. I tightened this down, which i'm not sure I should have as it
looks like some sort of pressure relief blow-off.
Any help would be greatly appreciated

It would be advisable to seek the help of a professional plumber with a
sealed hot water system qualification.

It would be even more advisable to switch the system off until you have done so

al wrote:

Help please for a rookie!!

I have a sealed pressurized heating system running off an oil-fired
burner. For some time now there has been a loss of pressure in the hot
water taps, to the point now where if one tap is on nothing will come
out of any other tap. The cold water is fine. When it was first
installed five years ago the hot water was the same pressure as the
cold.

Chances are you have a partial blockage in the inlet to the system, eg
a strainer may have slowly accumulated debris or a stone may have
passed into the system from the water main and be lodged somewhere
restricting the flow

I remember vaguely having a problem with a leak coming from the top of
my hot tank a couple of years ago from a little red knob which was
loose. I tightened this down, which i'm not sure I should have as it
looks like some sort of pressure relief blow-off.

No you definitely should not. I'm not sure anyone dim enough to do this
ought to work on your system!

On 23 Sep 2006 03:48:11 -0700 someone who may be "al"
wrote this:-

I have a sealed pressurized heating system

Hopefully it is not sealed, but has the variety of safety devices
specified for such systems.

Any help would be greatly appreciated

Get somebody who knows what they are doing to look at it. Hot water
under pressure is not something to experiment with.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

al wrote:
Help please for a rookie!!

I have a sealed pressurized heating system running off an oil-fired
burner. For some time now there has been a loss of pressure in the hot
water taps, to the point now where if one tap is on nothing will come
out of any other tap. The cold water is fine. When it was first
installed five years ago the hot water was the same pressure as the
cold.
I remember vaguely having a problem with a leak coming from the top of
my hot tank a couple of years ago from a little red knob which was
loose. I tightened this down, which i'm not sure I should have as it
looks like some sort of pressure relief blow-off.
Any help would be greatly appreciated

As far as I can tell, there's nothing on a relief valve that you can
screw down to stop it leaking which will also affect it's performance.
If it is a relief valve try testing it by lifting the lever or turning
the end - water should come out (maybe try it cold/warm not hot). Do a
google image search on a valve and see if it's the same.


There should be a one-way valve in the supply to the tank so maybe
that's got stuck.