Fixing a buffalo boiler cut out

[Simonh82]

I just picked up a second hand 20L buffalo water boiler for £20. I'm going to use for sparge water heating and for small test batches of BIAB. It has clearly been well used in a cafe and had thick limescale crusting the inside but after dumping serious quantities of malic acid in last night, I've got rid of a lot of the limescale, including clearing the base completely.

Despite this, I can't get the damn thing to even reach a boil. Even on the high setting it gets to 98°C and clicks off (light goes from orange to green). After dropping a few degrees it clicks back on again.

I know this is a common problem with buffalo boilers but I was hoping that I might be lucky with this one.

My guess is that it isn't the thermal cut-out as this is meant to kick in at 120° and mine doesn't even reach a boil. So how do I fix it?

My thought is that I could over-ride the thermostat completely. I'm happy to monitor temperatures manually instead but I don't know if this would work. If I did this, I would prefer to leave the 120°C thermal cut out in place as a safety back up but can remove if necessary. Does this sound like the right idea?

Thanks for any advice.

 

[Razor]

If you know what you're doing electronically and DIY minded enough then for £20 there's not too much to lose.


Sent from my iPhone using Tapatalk

 

[Simonh82]

If you know what you're doing electronically and DIY minded enough then for �£20 there's not too much to lose.

I'm not sure a screwdriver and boundless enthusiasm are recognised qualifications in the electrical industry but that's all i've got!

 

[Dutto]

What I do with all things electrical is to photograph everything from a variety of angles as I dismantle it.

This serves two purposes:

1. When I am confused I can post a photograph and ask someone what it is or what I do next.

2. When it's time to put everything back together I have photographic evidence of where things should go.

Since using this method I have never finished up with a "Grummet".

A "Grummet" being something left over from a bit of kit after dismantling it and putting it back together.

Over the years, various pieces of equipment have continued to operate properly without a "Grummet" (or "Grummets") so I have come to the conclusion that they are often installed just to confuse amateurs like me.

Very occasionally, the lack of a "Grummet" has spectacularly revealed itself with smoke and flames; at which point the purpose of the "Grummet" becomes apparent.

So following your own motto ("Rules are for the guidance of wise men but the obedience of fools.") I say "Go for it!" But take photographs and avoid finding any "Grummets". :whistle:

PS

I know what a "grommet" is and it can occasionally become a "grummit". :thumb:

 

[Simonh82]

I managed to open up the base, which was no easy feet as they hide the screws inside the feet and one of the screws as one of those specialist triangular bit types. Given my rudimentary electrical skills I decided to go with the easiest option first. I unscrewed the temperature probe for the thermostat and moved it away from the base. I left the thermal fuse/cut out switch alone completely. I had read that some people thought the thermostat was set to switch off at 98°C, which is exactly what was happening to me.

This seems to have fixed it so far. It is now maintaining a rolling boil. I'm half an hour in so far but previously I couldn't even reach a boil at all.

It means that I have to control the temperature manually now but I would have done that anyway for mashing.

I'm quite pleased that I managed to fix it without having to snip or rewire anything!

 

[BeerCat]

Good idea to move. Simplest solutions are often the best.

 

[sdt7618]

Now you have it boiling, could you use something like and inkbird to keep it at a set temp just? not sure if an inkbird probe could be boiled but there must be something that can.

 

[Dutto]

Now you have it boiling, could you use something like and inkbird to keep it at a set temp just? not sure if an inkbird probe could be boiled but there must be something that can.

Boiling any liquid is done at a temperature set by the liquid. (Pure water = 100 degrees.)

Therefore, all that can be controlled is the rate at which the liquid boils, not the temperature.

For a "rolling boil" most brewing systems have two elements. Both used to bring the wort up to boiling point and then just one used to maintain the "rolling boil" required during the boil.

My old electric El Cheapo only had the one 2.4Kw element and it took ages to bring the wort to the boil, but once there it maintained a superb rolling boil.

My current gas system takes the wort to boiling point quicker and the flame gets turned down to give the rolling boil required.

I may very well be wrong, but I would guess that if the constant boil is too fierce on the Buffalo Boiler the only "control" would be to keep turning it on and off manually.

 

[BeerCat]

I have ordered a 300m SS k type probe from China £12 which should be good for sticking in the mash.
Could you not just add a voltage controller to reduce the boil? I have the stuff but not tried it out yet. That's what i have been thinking of doing on my ace boiler so i can keep it on when mashing.

 

[Simonh82]

Now you have it boiling, could you use something like and inkbird to keep it at a set temp just? not sure if an inkbird probe could be boiled but there must be something that can.

I have an Ikea digital thermometer which has a long probe on a cable. This has an alarm which you can set for whatever temperature you want. I can leave this dangling in to the water and when the alarm goes off, I just switch it off.

For the boil, I'm happy with a good vigorous boil and that's what it seems to produce.

 

[Bigcol49]

I have ordered a 300m SS k type probe from China

Bugger me! That's some probe!

Seriously though, as I have a pumped recirculating system, I went down the route of the probe situated just after the outlet from the mash tun.

 

[Simonh82]

I have ordered a 300m SS k type probe from China �£12 which should be good for sticking in the mash.
Could you not just add a voltage controller to reduce the boil? I have the stuff but not tried it out yet. That's what i have been thinking of doing on my ace boiler so i can keep it on when mashing.

This 20L buffalo is mainly going to be used for a sparge water heater and occasionally for test batches I'm very happy to control it manually for this.

I did just win a PID with SSR and K-type sensor from Inkbird which I'm going to have a go at making a recirculating mash system with. I'm going to be using my main 30L Burco boiler for that, when I've worked out how to wire it up.

 

[Grizzly299]

I swapped out the thermostat in my Cygnet 27L for a simmerstat and bypassed the thermal cutouts. Which eliminates the temperature of the liquid being an issue. The simmer stat works more like a digital device in that it turns the power on and off at certain rate. That switching rate will achieve x temperature based on the volume of liquid. I'll be changing it out for the Inkbird PID, which I won in the giveaway, so that I have precision control over strike temps etc.

If anyone ever needs a hand with wiring, then I'd be happy to advise you.

 

[Simonh82]

I swapped out the thermostat in my Cygnet 27L for a simmerstat and bypassed the thermal cutouts. Which eliminates the temperature of the liquid being an issue. The simmer stat works more like a digital device in that it turns the power on and off at certain rate. That switching rate will achieve x temperature based on the volume of liquid. I'll be changing it out for the Inkbird PID, which I won in the giveaway, so that I have precision control over strike temps etc.

If anyone ever needs a hand with wiring, then I'd be happy to advise you.

I might need to pick your brains at some point. I've been scribbling half arsed wiring diagrams down, trying to get my head around how he PID controls the boiler.

One question you might be able to answer quickly is if I can wire the PID in before thermostat on my boiler as long as I leave it set to 'high'? This would be a lot simpler than running extra wires in and out of the base if it needs to connected after the thermostat (I know the thermostat will be redundant with the PID in place).

 

[Simonh82]

Bugger me! That's some probe!

Seriously though, as I have a pumped recirculating system, I went down the route of the probe situated just after the outlet from the mash tun.

I'd be interested in knowing how you set up your system. I'm looking to build a RIMs system with with my Burco boiler, a pump and PID controlling the mash temperature. I know most RIMs systems use an external heat source but I'd like to use the element in the Burco to heat the mash.

 

[Bigcol49]

I'd be interested in knowing how you set up your system.

Hi!
I have an ACE boiler/mash tun. I built a control panel with an Inkbird PID, SSR and temperature sensor. There is also a voltage regulator to reduce the power of the boiler's element during the mash - other members have found that the system flicks on and off constantly when the element is on full power.
The ball valve output feeds into a t-piece; the sensor is screwed into one "arm" of the t-piece, the other is connected to the pump. The pump feeds the wort back into the top of the boiler; I use a steamer rack at the top of the boiler to spread the flow so that the grain bed is not disturbed.
I also have a smaller boiler that I use as a HLT - this is also controlled by a PID.

 

[Grizzly299]

I might need to pick your brains at some point. I've been scribbling half arsed wiring diagrams down, trying to get my head around how he PID controls the boiler.

One question you might be able to answer quickly is if I can wire the PID in before thermostat on my boiler as long as I leave it set to 'high'? This would be a lot simpler than running extra wires in and out of the base if it needs to connected after the thermostat (I know the thermostat will be redundant with the PID in place).

Remember that your PID probably needs a Solid sate relay. I doubt that it has the capacity to switch a heating element directly.

In answer to your question yes, that is a perfectly viable way of wiring it. So the mains feed is being switched by both the SSR/PID and the existing stat in series.

You are just making what is essentially an "and gate" which means both conditions need to be true before the boiler will work.

The SSR needs to be Closed AND the Stat contact needs to be closed for the kettle to be on.

I wouldn't say that the stat is redundant. It could be useful as a way of keeping the kettle off whilst setting the PID? Ive never used a PID so I'm not 100% on all of its functions.

 

[Simonh82]

Hi!
I have an ACE boiler/mash tun. I built a control panel with an Inkbird PID, SSR and temperature sensor. There is also a voltage regulator to reduce the power of the boiler's element during the mash - other members have found that the system flicks on and off constantly when the element is on full power.
The ball valve output feeds into a t-piece; the sensor is screwed into one "arm" of the t-piece, the other is connected to the pump. The pump feeds the wort back into the top of the boiler; I use a steamer rack at the top of the boiler to spread the flow so that the grain bed is not disturbed.
I also have a smaller boiler that I use as a HLT - this is also controlled by a PID.

This sounds almost exactly like what I want to do. If you've got any more details of your build I'd be interested.

You've also clarified for me that a SSR isn't a voltage regulator. I think I had it in my mind that the PID varied the voltage with the SSR rather than just switching the current on or off.

If you have examples of the parts you used I'd love to know.

 

[Simonh82]

Remember that your PID probably needs a Solid sate relay. I doubt that it has the capacity to switch a heating element directly.

In answer to your question yes, that is a perfectly viable way of wiring it. So the mains feed is being switched by both the SSR/PID and the existing stat in series.

You are just making what is essentially an "and gate" which means both conditions need to be true before the boiler will work.

The SSR needs to be Closed AND the Stat contact needs to be closed for the kettle to be on.

I wouldn't say that the stat is redundant. It could be useful as a way of keeping the kettle off whilst setting the PID? Ive never used a PID so I'm not 100% on all of its functions.

Thanks Grizzly. The Inkbird PID that I won comes with a 25A SSR. I need to get a heat sink for it.

 

[Grizzly299]

Thanks Grizzly. The Inkbird PID that I won comes with a 25A SSR. I need to get a heat sink for it.

The way the PID works is by switching the output(SSR, which essentially just a switch) on and off a calculated number of times in order to reach and maintain your setpoint without overshooting. Older devices used to need manual tuning so that the system was stable, but most PID devices now autotune(thank god!). Ideally, if the system is stable, the temperature will even out the tinyest fraction below the setpoint, unlike with a standard thermostat. Where the temperature will oscillate around the setpoint quite dramatically, depending on what the hysteresis is like.

Having done some integration and differentiation during my degree time as well as studying Signals and Systems a little in the first and second years, I won't be going into the maths side of things :lol: Partly because I can't remember and partly because it's far too early to start looking at Laplace and Transfer Functions. Not to mention that I've not consumed nearly enough caffeine :whistle: .