TheScullster wrote:
Graham

Did all this last year and would suggest:

Get Vent Axia fan calculator brochure. This alerts you to other
important
considerations not just those to do with Vent Axia products.
E.g. the easiest way in the world to duct a fan is with crinkly hose,
but,
check how much this de-rates the fan based on hose length, numbers of
bends
etc. If you look at the cheapo shed packaged items (fan and hose,
maybe
light as well) you will see that the fan is rated at a reasonable
throughput
in free air, but drops to perhaps half this if the full length of
supplied
hose is used! Rigid duct is therefore recommended - plastic or
galvanised.

Decide on number of air changes - plenty of suggestions for this
already I
see.

Consider best position for vapour outlet - near toilet/shower/bath
and best
position for discharge to outside.

Look at duct route through ceiling and establish length of straight
and
number of bends.

Check with Vent Axia brochure what effect this will have on fan
performance
for a given fan/duct combination.

Adjust duct and fan size to give throughput acceptable to you.

I still think there is some mileage in paying premium for Xpelair or
Vent
Axia stuff. Other users claimed decent life expectancy for these
last year,
when I did mine. Would hate to go to all the trouble and have to
replace
the fan unit after 1-2 years.

Consider mounting fan on absorbent pads to minimise hum and putting
flexible
connections either side of fan.

Once happy with fan and duct arrangement, consider controls - timer,
humidistat, switching etc to suit.

HTH

Phil


I hate bathroom fans. If you dont have a window and must have one,

1. pick a large low speed unit, 9" or 12" rather than 6". This will
reduce noise.
2. forget 4"ers, theyre just a waste of time.
3. Use rubber washers at every mounting point you can to reduce noise.

It seems silly to use noisy annoying energy consuming fans when nature
will do the airshifting for you.
1. if you have a window, use it! Fit a lock that allows you to lock it
securely a half inch open. Silent, zero energy.
2. If no window, fit 2 tubes not 1, have the outlet ends pointing
opposite directions. No fan needed. It is fair to say you either need
larger ducting, or else to have them open for longer since the flow
rate is lower.


A humidistatic dehumidifier will avoid you throwing all that heat out,
and dehumidifes the whole house. And enables you to dump the tumble
dryer too.


NT