It is currently 21 Oct 2021, 02:26

Plumbing advice

Hang up your Chisels and Plane blades and take a load off with a recently turned goblet of your favourite poison, in the lounge of our Gentlemen's (and ladies) Club.

Plumbing advice

Postby Weekend_Woodworker » 11 Oct 2021, 13:46

I wondered if I can call on the collective wisdom of forum members to help solve a plumbing issue I am not sure how best to fix. The extractor fan for our main bathroom vents through our roof via some pipes in our loft. The geometry of the arrangements means that there is in effect a U-bend in the pipe. Whilst I have done my best to lag the pipe (some of which has been removed in the photo below) some of the steam still condenses in the pipe. Over time this water accumulates so that the pipe can become blocked and I have to go into the loft with a bucket to drain the water out. It is fairly infrequent e.g. once a year but I would like to avoid it. I can't easily get enough space to get the pipe out at the eaves so it only goes down hill, therefore I was wondering about trying to connect a small diameter pipe from the elbow going down to the eaves, however I am not sure how to make a good watertight connection to the plastic elbow. Does anyone have any advice or experience of how I might solve this please?

loft pipe picture.jpg
(423.19 KiB)


Many thanks,

Mark
User avatar
Weekend_Woodworker
Seedling
 
Posts: 40
Joined: 03 Apr 2021, 21:27
Name: Mark

Re: Plumbing advice

Postby 9fingers » 11 Oct 2021, 14:28

Change the left most 90 degree bend for a swept tee and use inter size adaptors (possibly need several) to get down to 22.5 overflow pipe. Run that to the eaves and outside. It will only produce the odd drips of water that can just fall to the ground.
A screwfix/ toolstation catalogue has loads of pictures of the various plumbing parts you could use

HTH
Bob
Information on induction motors here
https://drive.google.com/file/d/1dBTVXx ... sp=sharing
Email:motors@minchin.org.uk
User avatar
9fingers
Sequoia
 
Posts: 7771
Joined: 21 Jul 2014, 20:22
Location: Romsey Hampshire between Southampton and the New Forest
Name: Bob

Re: Plumbing advice

Postby Mike Jordan » 11 Oct 2021, 14:56

Why not simply run the existing size pipe horizontally to vent down through the soffit or facia board. Ie as 9fingers suggests but without reducing the pipe size.
Mike Jordan
New Shoots
 
Posts: 113
Joined: 10 Mar 2017, 17:06
Location: Littleover Derby.
Name: Mike Jordan

Re: Plumbing advice

Postby greeno » 11 Oct 2021, 15:42

We had a similar problem but ours was condensation forming on the outside of the duct. Lots of secondary insulation solved that.

If you don't want to permanent drain or feed it to the soffit, you can get insulated ducting, you can get flexible as well, so you could get rid of some of those bends.
greeno
New Shoots
 
Posts: 151
Joined: 19 Jul 2016, 10:46
Name:

Re: Plumbing advice

Postby sunnybob » 11 Oct 2021, 15:45

Hang on, I'm not getting it.
This is an extractor fan, yes? for air, not water.
Why does it need to be watertight?
Why is that shape?

assuming we are talking air flow, then cut the left hand pipe as high to the ceiling as you can, put a 90 degree elbow on, and connect the two ends with 2" flexible hose.
my wood projects are here https://pbase.com/sunnybob
User avatar
sunnybob
Old Oak
 
Posts: 1526
Joined: 17 Aug 2020, 10:59
Location: Cyprus
Name:

Re: Plumbing advice

Postby 9fingers » 11 Oct 2021, 16:18

sunnybob wrote:Hang on, I'm not getting it.


Sunnybob you have a fantastic ability to grasp the wrong end of the stick by only partial reading of the question.
Try a re -read and all should be come clear.

Bob
Information on induction motors here
https://drive.google.com/file/d/1dBTVXx ... sp=sharing
Email:motors@minchin.org.uk
User avatar
9fingers
Sequoia
 
Posts: 7771
Joined: 21 Jul 2014, 20:22
Location: Romsey Hampshire between Southampton and the New Forest
Name: Bob

Re: Plumbing advice

Postby sunnybob » 11 Oct 2021, 17:08

Its an air vent, and its getting condensation, what is there not to get?
Its getting condensation because of the length of it, and its collecting because of the u bend.
Remove the u bend, reduce the pipe to the absolute minimum length, and what condensation does occur it will be so slight as to not be noticed.
Connecting the fan to the light switch so it runs all the time the light is on will also reduce problems.

Or, take the pipe horizontally though the roof with a slight drop to the outside and the problem will never recur.
my wood projects are here https://pbase.com/sunnybob
User avatar
sunnybob
Old Oak
 
Posts: 1526
Joined: 17 Aug 2020, 10:59
Location: Cyprus
Name:

Re: Plumbing advice

Postby Lons » 11 Oct 2021, 22:42

My twopennerth having installed a quite a number of vented extractors through roof space though I've been retired a few years so fans may have changed in spec.

First: That is a poor design, there should not be a U bend in a vent pipe, it should have a smooth a passage as possible or it's not doing the job properly and overworking the extractor.

Second: That looks to me like standard 40mm waste pipe which in my experience is not large enough capacity, normally 100/110mm would be used or proprietary plastic expanding tube of similar dia

So you have several options.
Replace the pipe with the correct size and run it at an angle to rafter height using swept bends extract through the roof, you can reduce there to existing 40mm but only if you must, I wouldn't.

Similar using the expanding tube which is as cheap as chips, mine own are run at joist level as the stuff is easy to locate and insulate. Not as good as pipe as it's ridged but works fine.

Retain the existing pipe but re route similar to the first option above, I still think it's too small!

Live with what you have but replace the last bend with a tee and reduce one outlet to a drain off pipe routed to the outside or put a stopcock on the end so you can easily drain when you need to.
Lons
Nordic Pine
 
Posts: 554
Joined: 21 Jul 2014, 21:48
Location: Northumberland
Name: Bob

Re: Plumbing advice

Postby Weekend_Woodworker » 11 Oct 2021, 23:00

Thanks for all the replies. Bob (9 fingers) I like the idea you propose and will look into that. I understand SunnyBobs idea of just taking it all straight down to the eaves, but there isn’t enough space without changing the pipe diameter, and then I still have a pipe through the roof.

Best wishes,

Mark
User avatar
Weekend_Woodworker
Seedling
 
Posts: 40
Joined: 03 Apr 2021, 21:27
Name: Mark

Re: Plumbing advice

Postby Weekend_Woodworker » 12 Oct 2021, 13:16

Hi Lons, Sorry I missed your reply when responding last night. The pipe is actually 110mm diameter. I accept that the design is poor, and I will try and reduce the angle at the bend. Unfortunately the extraction for the bathroom is very close to the ridge, I can't get a 110mm pipe down to the eaves, I have an existing 110mm pipe through the roof and I don't like heights or have the access to change things outside on the roof. That all said the idea of taking a smaller pipe off the bend. I see in screwfix that they do a 110mm access bend which might be possible to fit another pipe to. They don't seem to do a T joint though.
User avatar
Weekend_Woodworker
Seedling
 
Posts: 40
Joined: 03 Apr 2021, 21:27
Name: Mark

Re: Plumbing advice

Postby 9fingers » 12 Oct 2021, 13:30

how about screwfix 29610. a socket plug 46863 to bung up the end, a boss adaptor 41571 into the side of the first item to get you to 32mm. then a 99045 reducer to get to 22.5 overflow pipe.

hth
Bob
Information on induction motors here
https://drive.google.com/file/d/1dBTVXx ... sp=sharing
Email:motors@minchin.org.uk
User avatar
9fingers
Sequoia
 
Posts: 7771
Joined: 21 Jul 2014, 20:22
Location: Romsey Hampshire between Southampton and the New Forest
Name: Bob

Re: Plumbing advice

Postby Alasdair » 12 Oct 2021, 15:06

This may sound too simpple but cant you just put a vent tile at ceiling hieght and connect the 4" grey pipe to that? eliminate the drop and u bend all together. IE run it horizontally where it comes through the bathroom wall and out to the fresh air?
Alasdair
New Shoots
 
Posts: 81
Joined: 28 Apr 2020, 17:42
Name:

Re: Plumbing advice

Postby Lons » 12 Oct 2021, 21:05

Hi Mark
My mistake it looks like 40mm but I shouldn't have assumed that. :oops:

Bob's suggestion of a boss is the easiest and cheapest solution if you can't re route it.
Lons
Nordic Pine
 
Posts: 554
Joined: 21 Jul 2014, 21:48
Location: Northumberland
Name: Bob

Re: Plumbing advice

Postby Deejay » 13 Oct 2021, 08:36

Morning Mark

https://www.toolstation.com/extractor-f ... low/p73185

Fitted above the fan. Continuous rise on the exhaust pipe to the outside air terminal.

Any condensation ( or rain entering the roof terminal) falls back to the trap and drains via the small radial outlet to a pipe with a continuous fall to the outside world.

Any good?

Cheers

Dave
User avatar
Deejay
Sapling
 
Posts: 353
Joined: 22 Jul 2014, 09:36
Location: Wiltshire
Name: Dave

Re: Plumbing advice

Postby Weekend_Woodworker » 13 Oct 2021, 12:57

Hi DeeJay,

I like that and wasn't aware such things exist. My slight snag is that I am working with 110mm pipe not 100mm. I could change the pipe from the extractor, but I couldn't readily change the bit going through the roof. :eusa-think:
User avatar
Weekend_Woodworker
Seedling
 
Posts: 40
Joined: 03 Apr 2021, 21:27
Name: Mark

Re: Plumbing advice

Postby flying haggis » 13 Oct 2021, 13:11

could that condensation trap have an outside diameter of 110mm?? would pop to ts and ask to see one. if it is 110 then a couple of straight couplings and job done
flying haggis
New Shoots
 
Posts: 126
Joined: 01 Oct 2019, 19:35
Name:

Re: Plumbing advice

Postby Deejay » 13 Oct 2021, 16:14

Weekend_Woodworker wrote:Hi DeeJay,

I like that and wasn't aware such things exist. My slight snag is that I am working with 110mm pipe not 100mm. I could change the pipe from the extractor, but I couldn't readily change the bit going through the roof. :eusa-think:

Hello Mark

Something like this might do, fitted on the vertical 110 pipe below the roof outlet ...

https://www.i-sells.co.uk/circular-adap ... m-to-100mm

Cheers

Dave
User avatar
Deejay
Sapling
 
Posts: 353
Joined: 22 Jul 2014, 09:36
Location: Wiltshire
Name: Dave

Re: Plumbing advice

Postby Lons » 13 Oct 2021, 23:30

You just need a boss like this one, several manufacturers have their own version, easily fitted from the outside yo your existing 110 soil pipe you can get these to take 19 or 20mm condensate pipe so no need for reducers. If I remember strap on type are available also.

https://mcalpineplumbing.com/traps/cond ... -connector
Lons
Nordic Pine
 
Posts: 554
Joined: 21 Jul 2014, 21:48
Location: Northumberland
Name: Bob

Re: Plumbing advice

Postby Weekend_Woodworker » 15 Oct 2021, 22:11

Thanks for all the ideas and suggestions. I liked the idea of the condensation collector, but then thought I might need two, one for each pipe that came down. The boss was a good idea, which would avoid the need to change the pipes, but I wasn’t sure how close I could connect it to the bend where I really wanted it. I have therefore decided to try these parts:
BBAC528A-2095-4BBB-BA0D-539974F24602.jpeg
(190.94 KiB)


Hopefully I can then fix this into the flat surface from the access panel which will allow me to run a pipe direct from the bend:

DCB972EA-83C9-468C-BDFA-604A1F43BC6B.jpeg
(183.97 KiB)


I had hoped to get the bits this weekend but I obviously spent too long pondering it and won’t have the bits till Monday. Hopefully I will be able to post a photo of it when it is all done if anyone is interested

Once again many thanks for all the help and ideas that have got me to this solution.
User avatar
Weekend_Woodworker
Seedling
 
Posts: 40
Joined: 03 Apr 2021, 21:27
Name: Mark


Return to The Woodmangler's Retreat

Who is online

Users browsing this forum: No registered users and 7 guests