Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?

Tim

--

On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.

--
Adam

ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

Tim
--

"Tim+" wrote in message
...
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

Never seen one of those thermostats do that, but I spose its possible.

Must be possible to measure its temperature set point now.

On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

Tim

bimetal stats can become sticky, sometimes sticking shut.


NT

wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.

"Tim+" wrote in message
...
"lopt" Wrote in message:


wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks
for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

That's an overload protector, not a stat, and so it can't have stuck shut
and caused the towel rail to overheat.

"lopt" Wrote in message:


wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

Tim
--

"lopt" Wrote in message:


"Tim+" wrote in message
...
"lopt" Wrote in message:


wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks
for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

That's an overload protector, not a stat, and so it can't have stuck shut
and caused the towel rail to overheat.



Maybe, but it's being used as a stat (and functions as a stat).
There is no other stat in the heater. The only other component in
the heater is a thermal fuse for "last ditch" overheat
protection.

Tim
--

"Tim+" wrote in message
...
"lopt" Wrote in message:


"Tim+" wrote in message
...
"lopt" Wrote in message:


wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major
overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks
for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

That's an overload protector, not a stat, and so it can't have stuck shut
and caused the towel rail to overheat.



Maybe, but it's being used as a stat (and functions as a stat).
There is no other stat in the heater. The only other component in
the heater is a thermal fuse for "last ditch" overheat protection.

But you said that it still switches, just at a different temp,
so it can't be sticking shut.

On Monday, 6 August 2018 00:22:34 UTC+1, lopt wrote:
tabbypurr wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:

Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.

I would expect it to be.


NT

On Monday, 6 August 2018 07:45:22 UTC+1, lopt wrote:
"Tim+" wrote in message
...
"lopt" Wrote in message:

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

That's an overload protector, not a stat, and so it can't have stuck shut
and caused the towel rail to overheat.



Maybe, but it's being used as a stat (and functions as a stat).
There is no other stat in the heater. The only other component in
the heater is a thermal fuse for "last ditch" overheat protection.

But you said that it still switches, just at a different temp,
so it can't be sticking shut.

error in logic captain. And a bit sketchy on facts.


NT

"lopt" Wrote in message:


"Tim+" wrote in message
...
"lopt" Wrote in message:


"Tim+" wrote in message
...
"lopt" Wrote in message:


wrote in message
...
On Sunday, 5 August 2018 21:23:32 UTC+1, Tim+ wrote:
ARW Wrote in message:
On 02/08/2018 22:13, Tim+ wrote:
Well I replaced the old overheating element with a new adjustable
one that has a boost timer which is a much better
idea.

I was curious as to where the stat was in to old element as it
just looked like a long road with an earth and two power
connections.

After a bit of hacksawing I extracted this which is, I presume, a
70C solid state stat of some sort.

https://photos.app.goo.gl/67pbhzeAExkhMa3i8
https://photos.app.goo.gl/suTh6zDybC5aLshz6

There's also a thermal fuse hidden under the shroud that I didn't
at first spot so I guess that would have provided major
overheat
protection.

Oddly, the stat still seems to work although I haven't checked the
temperature it switches off at there's no doubt that the rail
was getting much much hotter than normal.

Is it common (or even possible) for these stats to lose their
"proper" switching temp?



No idea if the stat could lose its proper switching temp but thanks
for
the photos.


Well I'm perplexed. There is no doubt in our minds that the towel
rail was overheating.

It had never made "simmering" noises before or heated the room to
a significant extent. It was doing both of those and felt much
much hotter to touch.

Today I got a glass lab thermometer and messed around with hot
water and my multimeter.

At 98c, stat contacts open. 90c, stat open, 80c, stat open. 69c,
stat closed. 70c, stat open.

So, in short, it seems to be behaving exactly to spec (assuming
the 70c printed on the side is the opening temp).

So, why was it overheating? Only thing I can think of is that the
switching temp moves after a period of operation.

Does this sound plausible?

bimetal stats can become sticky, sometimes sticking shut.

It isnt a bimetal stat.



Um, I think actually it is.

http://www.uchiya.co.jp/OtherContet/...glishHTML.html

That's an overload protector, not a stat, and so it can't have stuck shut
and caused the towel rail to overheat.



Maybe, but it's being used as a stat (and functions as a stat).
There is no other stat in the heater. The only other component in
the heater is a thermal fuse for "last ditch" overheat protection.

But you said that it still switches, just at a different temp,
so it can't be sticking shut.



No, I said the rail was overheating.

The puzzle for me is that the stat when tested appears to be
working exactly as expected. It goes open circuit @
70C.

I can only assume that it must go intermittently "sticky" and
allow overheating.

Tim
--

wrote:
On Monday, 6 August 2018 00:22:34 UTC+1, lopt wrote:

It isnt a bimetal stat.

I would expect it to be.

I cut it open today. It is indeed a bimetallic stat.

Tim


--
Please don't feed the trolls