Fitting an extractor to a boiler lid

[Vossy1]

The equipment,

Hydroponics fan bought from E-bay (inline)
A w/c pan connector straight (used for toilets (B+Q) )
Marley aluminium ducting 1m extendable to 3m (I bought this as I didn't want to have to support a floppy plastic duct
Ducting clips



Hole cut in lid with angle grinder



Bonded modified w/c pan connector to lid. Modified because I've cut the narrow threaded end of the connector (photo above)



The finnished item in-situ



The fan itself simply pushes into the w/c pan connector, as the w/c thingy has flexible rubberised flanges inside it

I'm going to have to raise the lid so as not to form a seal when the fan is on.

I turned the fan on and couldn't get the lid off due to suction

[kt88man]

Looks like you had fun cutting that hole in the lid, hope you followed all of the relevant H&S regulations

Noted also the aluminium ducting is fairly shiny, but not quite to the same degree as the stainless...

I turned the fan on and couldn't get the lid off due to suction

I wonder what the pressure drop actually was - creating a partial vacuum like that you'll lower the boiling point...

[Vossy1]

I wonder what the pressure drop actually was - creating a partial vacuum like that you'll lower the boiling point...

Hmmm, interesting point

[bod]

i thought of using a bathroom extractor fan from screwfix for my brewery in the same way. dont think i'll get as good suction on that though!!

you could do with a wee window to check how its doing, but that might steam up. let us know how it works when you brew next!

[Vossy1]

you could do with a wee window to check how its doing, but that might steam up. let us know how it works when you brew next!

My new HE tin has got a clear lid and when it gets to a certain point the condensation clears itself and you can see inside, so I might fit a window thingy to my boiler lid

Cheers bod

[Vossy1]

i thought of using a bathroom extractor fan from screwfix for my brewery in the same way. dont think i'll get as good suction on that though!!

Why not

They include everything according to the link Andy and DaaB gave me, gr8 value

Mine cost a total of £51, excluding cutting costs and I'm sure you could do it cheaper

I went for overkill as I can always scale back

[Vossy1]

Bringing this back to life because:-

Today was the 1st time I used my boiler with the extractor fitted and I had a few surprises:-

I normally use 2 elements to maintain a rolling boil with 60 ltr volume. One is PID controlled and one is on permanently.

My liquor hit a rolling boil, I turned the fan on and the temp went down to 96 with both elements flat out and was still going down

I had to wedge 3 pieces of 15mm copper between the lid and pan to prevent a vacumm being formed.

I turned the fan off and the water quickly returned to a rolling boil. I turned the fan on and the same happened again

I turned the fan off and removed the copper wedges, so the lid was on the pan and the liquor returned to the boil....but too vigourously

So, I turned the non PID controlled element off.

To my surprise the PID controlled element maintained a rolling boil, not only that but the PID was using the element intermittently

The seal between lid and pan didn't let steam into the kitchen, and the steam produced exited via the ducting

So the moral of this story is, if I can get away without using a fan on a 60 ltr boil, anybody using smaller volumes and at least a 2.4kw element shouldn't need a fan either

[Vossy1]

A question for the boffins

Whilst boiling I put a swan neck in the ducting above the fan.

At the end of the boil I removed the ducting and straightened the swan neck outside to remove any liquid which had accumulated.

A white liquid exited the ducting...like weak milk, and the liquid stank of solvent

The source was the fan

My question,

Even with the ducting some of the solvent will have got into the liquor.

I was using the liquor for making up a couple of kits, so only boiled for about 15 min!

Will it be safe

The liquor had a slight smell, but I'd say it was just like the smell you get from a hot fermenting bucket. It had no colour as such.

[eskimobob]

To my surprise the PID controlled element maintained a rolling boil, not only that but the PID was using the element intermittently

The seal between lid and pan didn't let steam into the kitchen, and the steam produced exited via the ducting

So the moral of this story is, if I can get away without using a fan on a 60 ltr boil, anybody using smaller volumes and at least a 2.4kw element shouldn't need a fan either

Interesting - so having a lid on seems to have enabled it to boil with a lower energy input (sounds reasonable) but at the same time you were able to vent the nasties contained in the steam. Sounds like win-win
How long was your aluminium ducting?
Could the residue have come from any lubricant that might have been on the inside of the ducting left over from manufacture?

Out of interest, the swan neck you fashioned sounds just like the shape of the chimney on the Howard Town brewery copper. They have a hole at the lowest point of the swan neck to which a hose is attached - the hose is placed in a bucket of water - any condensate that forms in the swan neck runs down the hose into the bucket.

[Vossy1]

How long was your aluminium ducting?
Could the residue have come from any lubricant that might have been on the inside of the ducting left over from manufacture?

The ducting is 1m unstretched, 4m stretched. I think I had about 1.5m in use.

I wondered about residue in the ducting, maybe even an oxidised layer on the aluminiun itself.

The residue stank of solvent, as did the fan. The fan smelt so strongly you could only sniff it as it was sooo overpowering a smell.

If it wasn't the fan, I'll find out when I brew. I've taken the fan off so if more residue appears in the swan neck it will probably be the ducting.

I know most metal ducting has a lubricant, usually a talc of some sort

I like the idea of the hole in the ducting to collect the condensate, as long as not too much steam gets into the kitchen

If like me, you put the ducting through an open window, place a cloth between duct and window frame, where they touch. The ducting gets very hot especially with a fan in use

The only thing I'm concerned about know is altering the amount of bittering hops in the boil.

The copper was sending a right old plume of steam out of the ducting even without the fan, so it shouldn't need any adjusting....hopefully

[Andy]

I don't like the sound of that solvent stuff Vossy, specifically the fact that some of the liquid is now in the wort!

Personally I'd bin the batch and then set about working out where the solvent is coming from - then do a test boil using water.

[Vossy1]

I don't like the sound of that solvent stuff Vossy, specifically the fact that some of the liquid is now in the wort!

Personally I'd bin the batch and then set about working out where the solvent is coming from - then do a test boil using water.

Test batch of water planned for this pm.

Luckily with the fan taken out of the equation, no plastic parts come into contact with the steam. I'll clean the ducting again prior to use, but hopefully that should be that.

Not sure about this, but I would have thought that leaching could also be a problem in plastic ducting, unless it's thermo stable placky

I'm going to run the batches on as there is no detectable smell in the wort and only a feint smell in the excess liquor that's still in the HLT this am

My wife likened the smell to putty

[Frothy]

bad luck vos man
I notice you'r using 2 different pumps there - what are they? Just about to fire up my totton for the first time.

Matt

[Vossy1]

bad luck vos man
I notice you'r using 2 different pumps there - what are they? Just about to fire up my totton for the first time.

May not be too bad...we'll see with time



Yep, 2 pumps Frothy. As you can see from the pic the march may (big black pump) has changed position again.

It's back in it's original position. I had problems with priming, which weren't rectified by placing the pump on the base. I introduced a priming valve, you can see it to the rear of the pump, the copper tube facing downwards, and the priming problem was irradicated.

I have to prime the set up in sequence.

At the front of the herms you can see two ball valves and to the rear of the pump a third.

The left hand valve is for the mash tun, the right for the hlt and the rear primes the pump.

First I open the valve from the HLT and then the valve at the back of the pump. This primes the pump itself.
I then close the valve at the rear of the pump.

Second, I open the valve to the mash tun. Liquor then flows into the mash tun from the hlt, purging air from the tubing as it does so. Then I close both the valves at the front.

The system is then primed

Thus, the march may pump can be used to pump the liquor into the mash tun and also to recirculate the mash

The second pump is the same Totton you've just bought. I use it to transfer the runnings to the hlt after sparging

[Bigster]

vossy wheres the flux capacitor I reckon you ought to change your avatar to the old geezer off back to the future

Nice work as usual mr constructor