Hi everyone,

I'm looking for advice on the "best" way to isolate my central heating pump

6 years ago I had 22mm pump valves fitted (these are the guys that
compression fit to the 22mm pipework, & then fit directly to the pump flange
with a (removeable from the fitting) large diameter backnut with a sealing
washer.

The pump failed over the weekend so I popped out, bought a new one & then
couldnt undo one of the backnuts. - I'm told this isn't unusual - & I think
I'm going to have to split this backnut to get the pump off

So 2 questions -

1 how can I remove the backnut from the pump - I can swing the isolating
valve & pump around the olive on the 22mm pipework! So the
backnut/washer/pump face are really tightly together! Ive tried bashing the
pump motor housing with a copper mallet while holding the isolating valve
body with mole grips - no good! There must be a magic way but I haven't
thought of it yet!

2 & what would you fit as isolating valves - are handle operated 90 degree
ball shut off valves any good over long periods of time?

I hope I've managed to explain the problem enough for you to understand what
I'm dealing with

TIA for any advice

Frank Sweeting





Frank Sweeting

Frank Sweeting wrote:

1 how can I remove the backnut from the pump - I can swing the isolating
valve & pump around the olive on the 22mm pipework! So the
backnut/washer/pump face are really tightly together! Ive tried bashing the
pump motor housing with a copper mallet while holding the isolating valve
body with mole grips - no good! There must be a magic way but I haven't
thought of it yet!

Have you tried heating the nut with a blowtorch for a bit? - a few
heating cycles can help break the bond. You could also just cut of a
short section of copper pipe either side and replace the isolating
valves at the same time.

Failing that you could split the nut off - nut splitter or a metal
cutting disc in a dremmel type tool.

2 & what would you fit as isolating valves - are handle operated 90 degree
ball shut off valves any good over long periods of time?

Not bad - if you get ones that do not restrict the flow rate (and hence
introduce extra water hammer noise).



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Wed, 01 Oct 2003 18:49:56 +0100, Frank Sweeting
wrote:



2 & what would you fit as isolating valves - are handle operated 90 degree
ball shut off valves any good over long periods of time?



I've used lever ball valves and found them fine over a 3 year period
so far.

Certainly they are better than gate valves.



..andy

To email, substitute .nospam with .gl

In article ,
Andy Hall writes:

I've used lever ball valves and found them fine over a 3 year period
so far.

Certainly they are better than gate valves.

Yes. I've had no problem with the pump, but have had to drain
the system down twice to fix the gate valves, which are only
there in the first place so you don't have to drain the system
down. Seems to be a logic fault there somewhere?

--
Andrew Gabriel

On 1 Oct 2003 20:09:56 GMT, (Andrew
Gabriel) wrote:

In article ,
Andy Hall writes:

I've used lever ball valves and found them fine over a 3 year period
so far.

Certainly they are better than gate valves.

Yes. I've had no problem with the pump, but have had to drain
the system down twice to fix the gate valves, which are only
there in the first place so you don't have to drain the system
down. Seems to be a logic fault there somewhere?

Exactly.

I've found the red wheeled ones to be bad enough - they stick and are
difficult to move when it's necessary to turn them off, and even when
closed they seep or even drip quite fast.

The ones that are built into pump unions are even worse, and I've
found that they can be very hard to move. You don't really want to
have to mess around with WD40 etc. and leave to soak when a pump needs
to be changed.

Ergo, last time, I put unions with compression fittings next to the
pump and then lever ball valves next to them.

Completely effective.





..andy

To email, substitute .nospam with .gl

Frank Sweeting wrote:

Hi everyone,

I'm looking for advice on the "best" way to isolate my central heating pump

6 years ago I had 22mm pump valves fitted (these are the guys that
compression fit to the 22mm pipework, & then fit directly to the pump flange
with a (removeable from the fitting) large diameter backnut with a sealing
washer.

The pump failed over the weekend so I popped out, bought a new one & then
couldnt undo one of the backnuts. - I'm told this isn't unusual - & I think
I'm going to have to split this backnut to get the pump off

So 2 questions -

1 how can I remove the backnut from the pump - I can swing the isolating
valve & pump around the olive on the 22mm pipework! So the
backnut/washer/pump face are really tightly together! Ive tried bashing the
pump motor housing with a copper mallet while holding the isolating valve
body with mole grips - no good! There must be a magic way but I haven't
thought of it yet!

2 & what would you fit as isolating valves - are handle operated 90 degree
ball shut off valves any good over long periods of time?

I hope I've managed to explain the problem enough for you to understand what
I'm dealing with


The 'magic' technique uses a large lump hammer as an anvil and your
copper mallet.
Put the lump hammer onto a flat of the of the ring nut but towards a
corner.
Whack the opposide face/corner with the copper mallet.
Try both directions - to get some movement into the ring - the inertia
of the pump body does half the work.
The lump hammer protects the pipework.

Some penetrating oil round the ring will help.
Put silcone grease on reassembly either you or someone unknown will
thank you in the future.








--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

Ed said:
"Put silicone grease on reassembly either you or someone unknown will
thank you in the future"

This is fantastic advice - always consider the future dismantling. Some
lubrication will always help. When I moved into a new house I dismantled my
taps and lubricated the mechanism and threads - they still work as smoothly
as new and are easy to dismantle if I need to replace washers.
Likewise - my garage door was well lubricated from new - many neighbours
have had theirs replaced due to breakages. At one time everyone had an
oilcan. Now they seem to be rare. Also a bit of Copperslip on the screws on
the C/H boiler ensure easy dismantling for servicing.



--


Regards

John

"Ed Sirett" wrote in message
...
Frank Sweeting wrote:

Hi everyone,

I'm looking for advice on the "best" way to isolate my central heating
pump

6 years ago I had 22mm pump valves fitted (these are the guys that
compression fit to the 22mm pipework, & then fit directly to the pump
flange
with a (removeable from the fitting) large diameter backnut with a
sealing
washer.

The pump failed over the weekend so I popped out, bought a new one &
then
couldnt undo one of the backnuts. - I'm told this isn't unusual - & I
think
I'm going to have to split this backnut to get the pump off

So 2 questions -

1 how can I remove the backnut from the pump - I can swing the isolating
valve & pump around the olive on the 22mm pipework! So the
backnut/washer/pump face are really tightly together! Ive tried bashing
the
pump motor housing with a copper mallet while holding the isolating
valve
body with mole grips - no good! There must be a magic way but I haven't
thought of it yet!

2 & what would you fit as isolating valves - are handle operated 90
degree
ball shut off valves any good over long periods of time?

I hope I've managed to explain the problem enough for you to understand
what
I'm dealing with


The 'magic' technique uses a large lump hammer as an anvil and your
copper mallet.
Put the lump hammer onto a flat of the of the ring nut but towards a
corner.
Whack the opposide face/corner with the copper mallet.
Try both directions - to get some movement into the ring - the inertia
of the pump body does half the work.
The lump hammer protects the pipework.

Some penetrating oil round the ring will help.
Put silcone grease on reassembly either you or someone unknown will
thank you in the future.








--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html


---
All of my outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.522 / Virus Database: 320 - Release Date: 29/09/2003

Andy Hall wrote:

Ergo, last time, I put unions with compression fittings next to the
pump and then lever ball valves next to them.

Completely effective.

Yup, same here, after learning the hard way that the standard
pump gate valves are a curse. A curse I tell ya.

--
Grunff

In article , John Rumm see.my.si
writes

Have you tried heating the nut with a blowtorch for a bit? - a few
heating cycles can help break the bond.

This is what worked for me, though I used an electric paint stripper.

--
A. Top posters.
Q. What's the most annoying thing on Usenet?

Thanx to all for your helpful comments

Regards: Frank Sweeting