I've just been to visit my son, and found the TRVs in his flat
completely stuck. I'm sure it's no coincidence that of the 5 rads, two
had odd TRVs and worked fine, and of the three of the same (presumably
original) type two had stuck wide open. However.... judicious use of an
Engineer's Adjuster unstuck the little pin in the valve, so I didn't
have to mess around with draining a system that's 3 hours from my home
(and my wet-and-dry vac, I haven't forgotten that trick). One of the
tops disintegrated, so I had to get a new valve - carefully picked for a
compatible top .

Anyway the point of the question is - now I've thumped them and got them
to behave, are they likely to go wrong again soon? Should I aim to swap
the lot out next time I'm up there?

Andy

(and another little story... as I logged in, aiming to type this up, I
noticed there was a noise of running water. Odd... doesn't seem to be
going anywhere... ah well, she just had a shower... odd... still
running... B****y valve on the main coldwater tank has stuck wide open,
it's spraying over the side of the tank, made a puddle on top of the
ceiling - and I wanted an early night. S** it, stopcock off, mop up
ceiling, job for tomorrow.)

On 2008-01-14 23:33:05 +0000, Andy Champ said:

I've just been to visit my son, and found the TRVs in his flat
completely stuck. I'm sure it's no coincidence that of the 5 rads, two
had odd TRVs and worked fine, and of the three of the same (presumably
original) type two had stuck wide open. However.... judicious use of
an Engineer's Adjuster unstuck the little pin in the valve, so I didn't
have to mess around with draining a system that's 3 hours from my home
(and my wet-and-dry vac, I haven't forgotten that trick). One of the
tops disintegrated, so I had to get a new valve - carefully picked for
a compatible top .

Anyway the point of the question is - now I've thumped them and got
them to behave, are they likely to go wrong again soon? Should I aim
to swap the lot out next time I'm up there?

Andy

They may do or they may not. 7 years is often mentioned for TRV
lifetimes - generally based on what happens to the wax arrangement in
the head.

I've always used Drayton (Invensys) TRV4s. This is over about 30
years and in different houses. I don't believe that I have ever had
less than 15 years life out of one.

I do also take care to ensure that the system is kept clean and topped
up with inhibitor and have never had a stuck valve as far as I can
remember.

I think it's likely that when the mechanism sticks for any length of
time, it screws up the thermostat mechanism in the head.

At any rate, if you are going to change a couple of TRVs, then in a
population of 5, it's far better to change the lot for TRV4s (don't be
tempted to buy cheap junk), and while you are at it to clean out the
system. It's the perfect opportunity to clean out any sludge and to
fill the system with a good quality inhibitor such as Fernox or
Sentinel.




(and another little story... as I logged in, aiming to type this up, I
noticed there was a noise of running water. Odd... doesn't seem to be
going anywhere... ah well, she just had a shower... odd... still
running... B****y valve on the main coldwater tank has stuck wide open,
it's spraying over the side of the tank, made a puddle on top of the
ceiling - and I wanted an early night. S** it, stopcock off, mop up
ceiling, job for tomorrow.)

That one is best resolved by making sure that the pipework is well
flushed out and replacing the valve with a Torbeck type.

In message 478c09f2@qaanaaq, Andy Hall writes
On 2008-01-14 23:33:05 +0000, Andy Champ said:

I've just been to visit my son, and found the TRVs in his flat
completely stuck. I'm sure it's no coincidence that of the 5 rads,
two had odd TRVs and worked fine, and of the three of the same
(presumably original) type two had stuck wide open. However....
judicious use of an Engineer's Adjuster unstuck the little pin in the
valve, so I didn't have to mess around with draining a system that's
3 hours from my home (and my wet-and-dry vac, I haven't forgotten
that trick). One of the tops disintegrated, so I had to get a new
valve - carefully picked for a compatible top .
Anyway the point of the question is - now I've thumped them and got
them to behave, are they likely to go wrong again soon? Should I aim
to swap the lot out next time I'm up there?
Andy

They may do or they may not. 7 years is often mentioned for TRV
lifetimes - generally based on what happens to the wax arrangement in
the head.

I've just had the head fail in one (a Pegler Terrier II) after about
18months, I was going to buy another identical one and just use the top,
anyone any comments before I do?



--
bof at bof dot me dot uk

In message 478c09f2@qaanaaq, Andy Hall writes
They may do or they may not. 7 years is often mentioned for TRV
lifetimes - generally based on what happens to the wax arrangement in
the head.

I've always used Drayton (Invensys) TRV4s. This is over about 30
years and in different houses. I don't believe that I have ever had
less than 15 years life out of one.

Interesting - I was thinking of starting a thread asking which brands
were reliable. Also saying that I wasn't going to get Drayton ones
again because about 3 of mine have stuck and need to be replaced. But I
think they are all over 15 years old, so maybe that's not too bad.

What surprised me browsing the local merchants is the huge range of
prices, from under 5 pounds to something like 30. Does anyone know if
the expensive ones are likely to last longer?

--
Clive Page

"Clive Page" wrote in message
...
In message 478c09f2@qaanaaq, Andy Hall writes
They may do or they may not. 7 years is often mentioned for TRV
lifetimes - generally based on what happens to the wax arrangement in the
head.

I've always used Drayton (Invensys) TRV4s. This is over about 30 years
and in different houses. I don't believe that I have ever had less
than 15 years life out of one.

Interesting - I was thinking of starting a thread asking which brands were
reliable. Also saying that I wasn't going to get Drayton ones again
because about 3 of mine have stuck and need to be replaced. But I think
they are all over 15 years old, so maybe that's not too bad.

What surprised me browsing the local merchants is the huge range of
prices, from under 5 pounds to something like 30. Does anyone know if the
expensive ones are likely to last longer?


IMHO Drayton TRV4's are the dog's b*ll*cks of TRV's (and are quite visually
attractive) and are not the cheapest. I suspect you get what you pay for!


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not) --
Clive Page

Clive Page wrote:

Interesting - I was thinking of starting a thread asking which brands
were reliable.

Danfoss.

--
Andy

On 2008-01-15 12:29:45 +0000, Clive Page said:

In message 478c09f2@qaanaaq, Andy Hall writes
They may do or they may not. 7 years is often mentioned for TRV
lifetimes - generally based on what happens to the wax arrangement in
the head.

I've always used Drayton (Invensys) TRV4s. This is over about 30
years and in different houses. I don't believe that I have ever had
less than 15 years life out of one.

Interesting - I was thinking of starting a thread asking which brands
were reliable. Also saying that I wasn't going to get Drayton ones
again because about 3 of mine have stuck and need to be replaced. But
I think they are all over 15 years old, so maybe that's not too bad.

I think that that's very reasonable.



What surprised me browsing the local merchants is the huge range of
prices, from under 5 pounds to something like 30. Does anyone know if
the expensive ones are likely to last longer?

I would shop around and get a good price on a complete set of TRV4s and
change the lot in one hit. Then forget it for the next 15 years.

Andy Hall wrote:

I think it's likely that when the mechanism sticks for any length of
time, it screws up the thermostat mechanism in the head.

That seems to be fine. It's only the valve bit that's stuck. Must
phone him and check it's all working OK.


My tank BTW was the fibre washer disintegrating (20 odd years old) and I
just happen to have a spare one which came off the CH header tank after
I replaced it because it kept overflowing - which turned out to be a
leaky coil.

Andy