Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

On Tuesday, 11 October 2016 11:46:15 UTC+1, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

Unlikely to be a motor fault. Only opening it will show what's sticky or damaged. Unfortunately you're right about reliability. I might get a used mechanical one if needed.


NT

Dan S. MacAbre wrote:
Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.
Lubricating the pallets might help but you can still get smiths type
rotary ones but the cost more than a digital LCD one.

wrote:
On Tuesday, 11 October 2016 11:46:15 UTC+1, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

Unlikely to be a motor fault. Only opening it will show what's sticky or damaged. Unfortunately you're right about reliability. I might get a used mechanical one if needed.


NT


What I was wondering about the motor is might it have been damaged by
not being allowed to turn. Once pushed past the point where it stopped
against the actuator, it turns okay, even past the other three
actuators. It's just the last one that stops it. I can't notice
anything when turned by hand, though.

It looks like you can get NOS ones, which will save a bit of rewiring.
Unless they're still actually making them, and what I'm looking at are
actually new ones?

Bob Minchin wrote:
Dan S. MacAbre wrote:
Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.
Lubricating the pallets might help but you can still get smiths type
rotary ones but the cost more than a digital LCD one.

Okay, thanks. I'll see if there's anything in there that might benefit
from lubrication. I had a quick look on eBay, and was surprised to find
that the rotary ones are more common. And there are plenty of direct
replacements still available.

A gear tooth could have worn away otherwise a clean and lube might fix it.

On Tuesday, 11 October 2016 14:21:33 UTC+1, Dan S. MacAbre wrote:
Bob Minchin wrote:
Dan S. MacAbre wrote:
Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.
Lubricating the pallets might help but you can still get smiths type
rotary ones but the cost more than a digital LCD one.

Okay, thanks. I'll see if there's anything in there that might benefit
from lubrication. I had a quick look on eBay, and was surprised to find
that the rotary ones are more common. And there are plenty of direct
replacements still available.

I wouldn't lube any part unless it was lubed from new, that's a classic way to cause such equipment to fail.


NT

wrote:
On Tuesday, 11 October 2016 14:21:33 UTC+1, Dan S. MacAbre wrote:
Bob Minchin wrote:
Dan S. MacAbre wrote:
Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered? My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away, that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.
Lubricating the pallets might help but you can still get smiths type
rotary ones but the cost more than a digital LCD one.

Okay, thanks. I'll see if there's anything in there that might benefit
from lubrication. I had a quick look on eBay, and was surprised to find
that the rotary ones are more common. And there are plenty of direct
replacements still available.

I wouldn't lube any part unless it was lubed from new, that's a classic way to cause such equipment to fail.


NT


Okay, I'll look for those dried-up black oily marks on anything that
might rub together. The back is held on with small starlock washers on
plastic posts, which is a bit of a nuisance.

DerbyBorn wrote:
A gear tooth could have worn away otherwise a clean and lube might fix it.


I've sometimes seen (e.g. in old zone valves) motor drive wheels that
sort of go concave over the years. If it's gone like that, I'll just
replace it.

On Tuesday, 11 October 2016 11:46:15 UTC+1, Dan S. MacAbre wrote:
If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

My experience of dismantling clockwork is to buy a new one first. At least that way you can have heating while you're crawling around on the floor trying to work out how many ping****its are now inside the dog.

Owain

On 11/10/2016 11:46, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered?

I have found that once the mechanical ones get to the point of
unreliability there is not usually much you can do for them. Either the
cams wear and fail to properly engage with the switch so you miss on or
off events, or they just get caught up and jam as yours does.

My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away,

That tends to be a particular Honeywell unit rather than a generic
problem affecting them all. I have found the Centaurstat ones quite good
- I had one in my last place that showed now indication of failure after
7 years or so.

that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

The main advantage of the digital ones is that you can have programmed
temperatures. So they in effect replace a time switch, and the stat.
plus you get the ability to preselect different temperatures at
different times of day - say warm when you wake up, cooler later, warmer
in the evening etc.

Some have an "optimising" capability where they learn the
characteristics of the house and switch the heating on early so as to
actually hit your demanded temperatures at the time you spec (so say you
say 20 degrees at 7am, a normal prog stat will turn the heating on at 7
and it will reach 20 some time later. The optimum start ones will work
out they need to turn it on so as to have it at 20 for 7am. Some people
find this handy, other find it irritating that it runs the heating at
unexpected times.

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

Its going to be less hassle to fit a known working one in that case.

--
Cheers,

John.

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

wrote:
On Tuesday, 11 October 2016 11:46:15 UTC+1, Dan S. MacAbre wrote:
If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

My experience of dismantling clockwork is to buy a new one first. At least that way you can have heating while you're crawling around on the floor trying to work out how many ping****its are now inside the dog.

Owain



I think I'll just get a new one, and be done with it.

John Rumm wrote:
On 11/10/2016 11:46, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered?

I have found that once the mechanical ones get to the point of
unreliability there is not usually much you can do for them. Either the
cams wear and fail to properly engage with the switch so you miss on or
off events, or they just get caught up and jam as yours does.

I think I'll get a new one, so that they can advance, boost, etc. 5/2
day timing won't make much difference to them, but you never know.

My first instinct isn't to go and buy a new
digital one, since I've had a few of these where the display just fades
away,

That tends to be a particular Honeywell unit rather than a generic
problem affecting them all. I have found the Centaurstat ones quite good
- I had one in my last place that showed now indication of failure after
7 years or so.

I've actually got a Grasslin QE2 that's lasted for about ten years. And
it was second-hand when I got it (I was fed up of buying new ones every
few years). It's just that before that, I always seemed to be replacing
them.

that I wouldn't automatically expect it to last anything like as
long as this old Randall thing. If the best thing is to buy a digital
one, because of the timing flexibility, are there any makes to look for,
or to avoid?

The main advantage of the digital ones is that you can have programmed
temperatures. So they in effect replace a time switch, and the stat.
plus you get the ability to preselect different temperatures at
different times of day - say warm when you wake up, cooler later, warmer
in the evening etc.

Some have an "optimising" capability where they learn the
characteristics of the house and switch the heating on early so as to
actually hit your demanded temperatures at the time you spec (so say you
say 20 degrees at 7am, a normal prog stat will turn the heating on at 7
and it will reach 20 some time later. The optimum start ones will work
out they need to turn it on so as to have it at 20 for 7am. Some people
find this handy, other find it irritating that it runs the heating at
unexpected times.

Bloody luxury :-) When I was a lad, we had a coal fire in the front
room and a back boiler. Strange, but I don't remember ever feeling
cold. Our little boy's the same - never wears pyjamas, even in winter,
and always kicks the covers off in his sleep. Weird.

If this was at home, I'd already have dismantled the thing, but it's not
so easy to try things out when there's a journey involved.

Its going to be less hassle to fit a known working one in that case.

On Tuesday, 11 October 2016 17:42:25 UTC+1, Dan S. MacAbre wrote:
Bloody luxury :-) When I was a lad, we had a coal fire in the front
room and a back boiler. Strange, but I don't remember ever feeling
cold.

I do.

Modern programmers often have a 'holiday' setting which might be useful.

Owain

On Tuesday, 11 October 2016 17:42:25 UTC+1, Dan S. MacAbre wrote:
John Rumm wrote:
On 11/10/2016 11:46, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered?

I have found that once the mechanical ones get to the point of
unreliability there is not usually much you can do for them. Either the
cams wear and fail to properly engage with the switch so you miss on or
off events, or they just get caught up and jam as yours does.

I think I'll get a new one, so that they can advance, boost, etc. 5/2
day timing won't make much difference to them, but you never know.

One problem with digitals is they can be far from trivial to operate. Add people with no willingness to learn to program them and they're a (minor) disaster.


NT

wrote:
On Tuesday, 11 October 2016 17:42:25 UTC+1, Dan S. MacAbre wrote:
John Rumm wrote:
On 11/10/2016 11:46, Dan S. MacAbre wrote:

Mum and dad's Randall 102 seems to stick on the last 'off' actuator, so
that it doesn't move after 11PM, and the heating stays on all night. I'm
considering whether to try and repair it, or replace it. Has anyone
here seen one with the same problem, and managed to fix it? Or will the
motor now be nackered?

I have found that once the mechanical ones get to the point of
unreliability there is not usually much you can do for them. Either the
cams wear and fail to properly engage with the switch so you miss on or
off events, or they just get caught up and jam as yours does.

I think I'll get a new one, so that they can advance, boost, etc. 5/2
day timing won't make much difference to them, but you never know.

One problem with digitals is they can be far from trivial to operate. Add people with no willingness to learn to program them and they're a (minor) disaster.


NT


I think it's because it's one of those things you only do every five
years, or something. I'll have to set it for them, and hope they leave
it alone.