Buffalo Boiler 27L - help needed with electrics

[jmc]

Hi
About 2 months ago I bought a second-hand buffalo boiler.
Ex tea-urn. 27L. 3Kw. Model J520.

At first it boiled really well, but now its taking much longer to get to temp.
And it won't give a constant rolling boil

At 3Kw it has the potential to be really good, but even on the 110C temp dial setting the heater clicks on and off right from the start.
Much more than it used to and unfortunately its more off than on.
I'm thinking of modifying the electrics. see pic below.


It wouldn't be too difficult to move the temperature sensor that seems to be stuck with strong tape to the base.
But before I do this it would be useful to know if this will help or not.

Element is slightly coloured (brown) and pitted, but no visible residue.
I'll give it a clean with citric acid too to see if this helps.

Any suggestions for how I should modify the electrics or any other ideas?

TIA for any suggestions.
ATB
John

[stu-le-brew]

suggestion, before you start modifying the electrics, especially as it did work well once, I remember having such problems with my Burko which was actually caused by the heating element having a build up of caramelized beer on the element. It depends on the style of the element, mine was in the shape of a butterfly, I used to remove it with acid (hydrochloric)

[jmc]

Hi Stu

Thanks for the suggestion. I was thinking of cleaning using citric first as I have some to hand.

Element is flat, but it is old and pitted, so maybe more build up than it looks.
All else shiny apart from this.

If I used hydrochloric acid what strength would you use?
Would stuff here be OK: http://www.mistralni.co.uk/details.php?id=70
TIA
John

[stu-le-brew]

sorry I am not sure on strength, I just buy it from local hardware store here (just used last lot on cleaning a fermenter so can't check), I remember reading somewhere that Nitric acid is the best. I pour in on neat then leave in contact for 10mins then wash/rinse a lot then use a plastic scouring pad to clean.

Citric acid may also work but heat the water using the element, I use citric to adjust the PH in my HLT the copper metal temperature probe is really bright after use - again use use a plastic scouring pad to clean.

[jmc]

Hi Stu

I used about 1oz of citric acid in about 1/2 pint water to clean the element today.

I pulsed heat to element to focus cleaning. It did clean a bit, but no huge amount of debris removed.
See before & after below



I did a quick test post-clean before the match (Germany v Spain)
and 4L water came to boil in about 5-7min with no cutout.

Proof of the pudding will of course be 27L wort boiling for 90 mins once thermostat sensor gets hot. I'll test ASAP.

BTW still interested in wiring options and whether I should relocate thermostat sensor.
ATB
John

[stu-le-brew]

The control on this boiler is different from my old one, which used a simmer stat (which worked but I never understood it) which controlled the current, but the main difference was that it did not have a temperature probe.

My suggestion is that it is either the its temp probe that's got a leak or the switch is not working properly, first step would be to detach the temp probe from the base and see what difference this makes, assuming this changes the way your boiler works it would be simplest to just replace the switch/temp probe - I would assume that you buy them as one unit.

hope this helps

EDITI just remembered that my old boiler had an over temp gizmo which had to be disconnected to ensure the boiler would boil, not sure about yours. This may be a red herring as your boiler did work OK before

[jmc]

Hi Stu

Sorry too hot over past few days to do a boil test. Its cooled down a bit now and I've taken your advice and I've moved the (thermostat / simmerstat? ) sensor/probe.

There was a loop of stainless steel spot welded to the base of the boiler and the probe was fitted there, covered in a silvery tape.

After removing tape it looked like there was white (thermal?) paste between the probe and the boiler base.
I found that the sensor was fitted quite tight. I didn't want to force the loop and cause a leak, so I very gently opened loop a bit, with a small screwdriver and it then could be pushed past the loop.

I duck-taped it to the side of the base, at 90deg to the base. Pics below show stages of moving semsor.
No electrics changed so hopefully all should be OK in test run, hopefully tomorrow. I'll update post as soon as I've done a roiling boil test.

[jmc]

Hi Stu
I did a test boil of 16L of water and boiler is much improved.

Turned up dial to full (106C) and water heated to rolling boil with no thermostat/simmerstat cut out at all.

I think its primarily due to moving the sensor, but the clean may have helped suppress any thermal cutout kicking in on the element.

Once on a rolling boil I could stop the boil by turning dial to about 45 C. Clearly wrong temp, but it means I can still 'simmer' when needed.

Next test will be with 27L of wort. I'll tell you how I get on then.
Thanks again for the advice.
ATB
John

[jmc]

Hi

Boiler much improved after moving thermostat sensor
First proper full boil on Saturday.
Nice rolling boil as below. No cut out.


27.5L of GW Timothy Taylor clone.
boiled down to 23L in 90 min


Still need to keep element clean: On Sunday I did a quick Breferm Belgian Tripel kit.
A few minutes after malt extract hit element the simmerstat kicked in. It only did it for about 5 mins

I think there is still a thermal cutout / overheating sensor in element that affects boil as well.

This was a small kit (9l) with high % malt extract (1.066), so its a bit unusual.
I think as long as I keep element clean I'll be OK.


ATB
John

[jmc]

Boiler has done its job for last 38 AG brews, but recently thermal cut-out proving to be a real PITA.

I would appreciate some advice on changes in boiler wiring to bypass thermal cut-out.

After each brew I scrub element and clean with citric acid, but I'm finding that about 60-70 mins into boil it starts to cut out
This is much worse if I do mash+sparge in evening and boil next day.

I previously moved thermostat linked to temp dial and this helped, but there is an additional thermal cut out on the element.

I want to by-pass this and I'd appreciate feedback, prior to a test

Basically I just want to connect the 2 neutral together (those into & from thermal cut-out)
& 2 live cables together (ones into & from thermal cut-out)

After change, only cable left going to thermal cut out would be the earth.

Is proposed cabling OK?

I've included 2 pictures of cabling prior to change and last one with proposed new connections (prior to proper insulation)






Thanks in advance for your help

[Kev888]

Hi,
With the caveat that I don't have an element like this, the alterations look like they'd do the job to me.

I can't tell from the picture, but if the spades are compatible and if the wires reach, could you just remove the short linking wires altogether and connect the longer wires direct to the element terminals? If so it would save a join, which is always a weak spot.

Also, keep a careful eye on the boiler afterwards; it is most probable that the overheat sensor/switch is just getting over-sensitive, but theres also 'some' chance that the element may actually be getting too hot for some reason.

Cheers
kev

[jmc]

Hi,
....
I can't tell from the picture, but if the spades are compatible and if the wires reach, could you just remove the short linking wires altogether and connect the longer wires direct to the element terminals? If so it would save a join, which is always a weak spot.
...
Cheers
kev

Hi Kev
Thanks for looking at (very poor pics)
Good idea to remove short wire, but its female-female spade ends are just the job to connect male spade from rotary thermostatic switch to element male.

Looking at thermal cut out closely it does look like there was a hot spot.
I'm now wondering if spade connection wasn't tight enough. It did come out very easily
There was a similar post recently about a boiler with thermal-cut-out tripping due to hot spade connection.
Thanks again for your help. ATB John

I will ensure everything is a tight-fit & properly insulated before testing.

[Redbloke]

Hi jmc,
Did this work for you? I've recently had my first 'cut out' experience with my Buffalo boiler, luckily after 85 minutes boiling, so nothing to panic about, ... yet! I make sure the element is sparkling clean after each brew but it has still been struggling recently.
It would be useful to have a definitive solution to this post as I'm sure others might have the same problem.

Cheers

[jmc]

Hi jmc,
Did this work for you? I've recently had my first 'cut out' experience with my Buffalo boiler, luckily after 85 minutes boiling, so nothing to panic about, ... yet! I make sure the element is sparkling clean after each brew but it has still been struggling recently.
It would be useful to have a definitive solution to this post as I'm sure others might have the same problem.

Cheers

Hi Redbloke

Sorry for not updating post.

Pleased to report that this totally fixed problem I had with over-sensitive cutout.

I've had 4 AG brews since changing electrics on boiler and no hint of a cut out, to the extent that I just don't worry about it any more.

After brew I still scrub element with plastic washing up brush until no visible residue but that's it now.
No Citric acid scrub, scrub after each brew to hopefully avoid the PIA cut out.
Happy days

[danielsan]

Hi guys

I've been suffering the same problem on my 40l Buffalo, inspired on your solution i've insulated the probe in a small piece of silicon tube.




I've brewed today and it worked. The alcohol thermometer was showing a difference of about 10ºC vs the temp controller of the Buffalo. During the boiling I kept the temp in 100º instead of the maximum 110º, and it was a nice uninterrupted boiling. Sweet.


Thanx for the idea!