My Manrose SF120T (125 mm in-line fan) sounds, from intermittent
bearing noise, as if it is about to fail.

Although the two I have had so far have given reasonable life for
an inexpensive item, I think it is time to consider a more robust
model.

I am looking for a quiet, capable, 125 mm duct fan, with run-on
timer, to fit into existing flexible ducting for my bathroom.

The MF125T looks the best match, but I am waiting for a response
from the supplier about its high/low speed configuration. Does
anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Tue, 19 Feb 2013 09:27:06 +0000, Chris J Dixon
wrote:

My Manrose SF120T (125 mm in-line fan) sounds, from intermittent
bearing noise, as if it is about to fail.

Although the two I have had so far have given reasonable life for
an inexpensive item, I think it is time to consider a more robust
model.

I am looking for a quiet, capable, 125 mm duct fan, with run-on
timer, to fit into existing flexible ducting for my bathroom.

The MF125T looks the best match, but I am waiting for a response
from the supplier about its high/low speed configuration. Does
anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?


You may want to have a look at the quiet S&P in-line units
http://www.tlc-direct.co.uk/Products...ENTslashT.html
We have one for a bathroom/shower extract and it seems to be an
improvement on the Manrose equivalent and has a noticeably better
noise/air movement result.

As a kitchen extract we have a two speed in-line Vent Axia (without
timer) ACM 125 which is somewhat noisier but is effective and very
easy to demount for cleaning.
--
rbel

rbel wrote:

You may want to have a look at the quiet S&P in-line units
http://www.tlc-direct.co.uk/Products...ENTslashT.html
We have one for a bathroom/shower extract and it seems to be an
improvement on the Manrose equivalent and has a noticeably better
noise/air movement result.

Thanks for that, it looks interesting, if a little expensive. I
hadn't found it on TLC's site when I looked, as they don't list
it under "Shower & Inline Duct Fans"

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Tuesday, February 19, 2013 9:27:06 AM UTC, Chris J Dixon wrote:

I am looking for a quiet, capable, 125 mm duct fan, with run-on
timer, to fit into existing flexible ducting for my bathroom.
The MF125T looks the best match, but I am waiting for a response
from the supplier about its high/low speed configuration. Does
anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?
Chris

You can speed reduce a fan with a series capacitor. However no mfr will recommend starting a fan on reduced setting, it significantly increases the onset of failure. A possible solution is a 3 position switch or a time delayed relay (diode, RC) so the fan comes on at full then quickly switches to reduced speed.


Plant amazing Acers.

Surely fruiting trees are more use


NT

On 19/02/2013 14:28, wrote:
On Tuesday, February 19, 2013 9:27:06 AM UTC, Chris J Dixon wrote:

I am looking for a quiet, capable, 125 mm duct fan, with run-on
timer, to fit into existing flexible ducting for my bathroom.
The MF125T looks the best match, but I am waiting for a response
from the supplier about its high/low speed configuration. Does
anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?
Chris

You can speed reduce a fan with a series capacitor. However no mfr will recommend starting a fan on reduced setting, it significantly increases the onset of failure. A possible solution is a 3 position switch or a time delayed relay (diode, RC) so the fan comes on at full then quickly switches to reduced speed.


Plant amazing Acers.

Surely fruiting trees are more use


NT

Not sure fruit is any more use than sugar, is it?

--
Rod

On 19/02/2013 09:27, Chris J Dixon wrote:
My Manrose SF120T (125 mm in-line fan) sounds, from intermittent
bearing noise, as if it is about to fail.

Although the two I have had so far have given reasonable life for
an inexpensive item, I think it is time to consider a more robust
model.

Is it not possible to replace the bearings?

SteveW

On Tuesday, February 19, 2013 3:50:24 PM UTC, polygonum wrote:
On 19/02/2013 14:28, wrote:
On Tuesday, February 19, 2013 9:27:06 AM UTC, Chris J Dixon wrote:

Plant amazing Acers.

Surely fruiting trees are more use

Not sure fruit is any more use than sugar, is it?

Maples produce dilute sap that takes time & skill to harvest, and is a right hassle to concentrate into syrup. Hence I know no-one that does it. Fruit OTOH is immediately usable by most people, and used by a huge number.


NT

wrote:

On Tuesday, February 19, 2013 9:27:06 AM UTC, Chris J Dixon wrote:

I am looking for a quiet, capable, 125 mm duct fan, with run-on
timer, to fit into existing flexible ducting for my bathroom.
The MF125T looks the best match, but I am waiting for a response
from the supplier about its high/low speed configuration. Does
anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?
Chris

You can speed reduce a fan with a series capacitor. However no mfr will recommend starting a fan on reduced setting, it significantly increases the onset of failure. A possible solution is a 3 position switch or a time delayed relay (diode, RC) so the fan comes on at full then quickly switches to reduced speed.

As it happens, in this particular case, the real answer is
different. Manrose has just advised:

"Yes it is possible to permanently wire the MF125T to the Low or
High speed setting without using a speed controller. When you
wire the fan up place the Neutral wire into the terminal marked
S1(sometimes denoted as N1) on the fan for the low speed or S2 on
the fan for high speed (sometimes denoted as N2)."

Plant amazing Acers.

Surely fruiting trees are more use

Life is a bit dull when confined to utility.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Saturday, February 23, 2013 8:12:17 AM UTC, Chris J Dixon wrote:
wrote:
On Tuesday, February 19, 2013 9:27:06 AM UTC, Chris J Dixon wrote:

anybody know if it is possible to permanently connect in low
speed without the expense of the separate speed control box?
Chris

You can speed reduce a fan with a series capacitor. However no mfr will recommend starting a fan on reduced setting, it significantly increases the onset of failure. A possible solution is a 3 position switch or a time delayed relay (diode, RC) so the fan comes on at full then quickly switches to reduced speed.

As it happens, in this particular case, the real answer is
different. Manrose has just advised:
"Yes it is possible to permanently wire the MF125T to the Low or
High speed setting without using a speed controller. When you
wire the fan up place the Neutral wire into the terminal marked
S1(sometimes denoted as N1) on the fan for the low speed or S2 on
the fan for high speed (sometimes denoted as N2)."

Fair enough. It won't last as long that way, hence fans are always started at full power initially by controllers.


NT

wrote:

On Saturday, February 23, 2013 8:12:17 AM UTC, Chris J Dixon wrote:

As it happens, in this particular case, the real answer is
different. Manrose has just advised:
"Yes it is possible to permanently wire the MF125T to the Low or
High speed setting without using a speed controller. When you
wire the fan up place the Neutral wire into the terminal marked
S1(sometimes denoted as N1) on the fan for the low speed or S2 on
the fan for high speed (sometimes denoted as N2)."

Fair enough. It won't last as long that way, hence fans are always started at full power initially by controllers.

You seem to be discounting the possibility that the motor winding
has been specifically designed for just such performance.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Saturday, February 23, 2013 10:05:44 AM UTC, Chris J Dixon wrote:
wrote:
On Saturday, February 23, 2013 8:12:17 AM UTC, Chris J Dixon wrote:

As it happens, in this particular case, the real answer is
different. Manrose has just advised:
"Yes it is possible to permanently wire the MF125T to the Low or
High speed setting without using a speed controller. When you
wire the fan up place the Neutral wire into the terminal marked
S1(sometimes denoted as N1) on the fan for the low speed or S2 on
the fan for high speed (sometimes denoted as N2)."

Fair enough. It won't last as long that way, hence fans are always started at full power initially by controllers.

You seem to be discounting the possibility that the motor winding
has been specifically designed for just such performance.

If the manufacturer says its ok, then its reasonably obvious that it has been designed to do the job. That of course has no bearing on the reality that it will start with less torque at this setting, thus fail earlier.


NT

On 23/02/2013 15:48, wrote:
If the manufacturer says its ok, then its reasonably obvious that it has been designed to do the job. That of course has no bearing on the reality that it will start with less torque at this setting, thus fail earlier.

If it gets a bit stiff in its old age, and won't start, doesn't he just
need to move it to the other setting to give it a kick?

And if it's running at low speed for the moment won't it take longer to
wear out its bearings to the extent it needs the kick?

Andy

On 19/02/2013 17:53, SteveW wrote:
On 19/02/2013 09:27, Chris J Dixon wrote:
My Manrose SF120T (125 mm in-line fan) sounds, from intermittent
bearing noise, as if it is about to fail.

Although the two I have had so far have given reasonable life for
an inexpensive item, I think it is time to consider a more robust
model.

Is it not possible to replace the bearings?

SteveW


In principle; they are usually self aligning oilite bushes but the
carriers often seem to be motor-specific. A spray of WD40 or similar
often quietens them down for a good while, or a dribble of 3 in 1
provided you can get it in just the right place.

On Saturday, February 23, 2013 9:05:47 PM UTC, Andy Champ wrote:
On 23/02/2013 15:48, wrote:

If the manufacturer says its ok, then its reasonably obvious that it has been designed to do the job. That of course has no bearing on the reality that it will start with less torque at this setting, thus fail earlier.

If it gets a bit stiff in its old age, and won't start, doesn't he just
need to move it to the other setting to give it a kick?
And if it's running at low speed for the moment won't it take longer to
wear out its bearings to the extent it needs the kick?
Andy

If it hasn't fried itself or caught fire, yes. But they often fry, and sometimes burn.


NT

On Saturday, February 23, 2013 9:49:56 PM UTC, newshound wrote:
On 19/02/2013 17:53, SteveW wrote:
On 19/02/2013 09:27, Chris J Dixon wrote:

Is it not possible to replace the bearings?

In principle; they are usually self aligning oilite bushes but the
carriers often seem to be motor-specific. A spray of WD40 or similar
often quietens them down for a good while, or a dribble of 3 in 1
provided you can get it in just the right place.

WD40 is a solvent, white spirit. That frees it up temporarily, but soon evaporates, just leaving less lube in the bearings. Ideally what's wanted is to clean out and regrease the bearings. Next best is lots of oil, sometimes that works well enough, sometimes not.


NT

On 23/02/2013 23:01, wrote:
If it hasn't fried itself or caught fire, yes. But they often fry, and sometimes burn.

Ah. I've always had fans fail the "unacceptably noisy" test first.
Perhaps computer fans are built to different specs. (I used one for many
years in an extractor... until it got too noisy)

Andy

rbel wrote:

You may want to have a look at the quiet S&P in-line units
http://www.tlc-direct.co.uk/Products...ENTslashT.html
We have one for a bathroom/shower extract and it seems to be an
improvement on the Manrose equivalent and has a noticeably better
noise/air movement result.

Finally got round to fitting it, which involved contortions in
the limited roof space.

It really is quiet, you actually need to feel the airflow to
believe it is running.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On 19/03/2013 14:51, Chris J Dixon wrote:
rbel wrote:

You may want to have a look at the quiet S&P in-line units
http://www.tlc-direct.co.uk/Products...ENTslashT.html
We have one for a bathroom/shower extract and it seems to be an
improvement on the Manrose equivalent and has a noticeably better
noise/air movement result.

Finally got round to fitting it, which involved contortions in
the limited roof space.

It really is quiet, you actually need to feel the airflow to
believe it is running.

Well at that price it needs to be!

I fitted a cheapo, allegedly silent model in our roof space years ago,
for our en suite; it quickly became apparent that 'silent' it was not.
Naturally I was charged with the task of replacing it; however it was
fortunate that that particularly round tuit never came home to roost,
since SWMBO actually likes it now, as a white noise generator - firstly,
to conceal bathroom 'noises' which apparently girls don't like (either
their own or other people's) [1]; secondly, to muffle any 'bedroom'
noises from us, which becomes an issue when the kids are old enough to
stay up as late as you do, and thirdly, to drown out the noise of
squabbling teens downstairs if she's having an early night.

So, no more plans to change the extractor...

--
David