BZ gen 4 heat diffuser plate. A question re fitment.

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Frisp

Frisps 2 Firkin Brewery
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I bought the heat diffuser plate for the BZ gen 4 when I bought it..

On fitting I notice the plate, when attached to the false bottom , sits directly on top of the temp probe in the base.
This means the FB assembly does not sit level in the bottom of the BZ..
It infact coggles a bit, with the temp probe acting like a tiny fulcrum..
I know the False bottom on the BZ isnt a snug fit but this makes the gap a couple of mm wider in places

Is this normal.. as Im thinking the bottom temp probe should be measuring the liquid temp not the heat diffuser plate?
 
It is normal but if it concerns you just drill a small hole in the heat diffuser just to allow the probe room to sit through it.
A small hole of a few mm will suffice I would think the only downside is it will allow the wort to run through it onto the probe albeit a very small amount if the hole is made snug
 
It is normal but if it concerns you just drill a small hole in the heat diffuser just to allow the probe room to sit through it.
A small hole of a few mm will suffice I would think the only downside is it will allow the wort to run through it onto the probe albeit a very small amount if the hole is made snug
Ill see whether it affects a brewday or not before I go drilling, I was starting t worry the probe was too long or something..
 
I have the G4 35L with heat plate. Purchased Oct 23. Tye base hsits firmly on it's three feet, and certainly doesnt rock.

I've seen something about later models having the temperature probe moved, to further away from edge (where more wort flows). And that with early models, the heat plate needed a cutout (for the probe) and the base had to to be put in with matching orientation.
So possibly you've got an incompatible mix of old and new stock.

On mine the probe is 6cm (2 1/4 inch), in from the outer edge. On early model pictures, it looked about 1cm.

Other possibility is having plate on the wrong way up. Photos might help.
 
Is this normal.. as Im thinking the bottom temp probe should be measuring the liquid temp not the heat diffuser plate?
I don't think it's normal, mine certainly doesn't come in contact with the temperature probe.
As previously mentioned , the temperature probe has been moved since the very early models.
Do you have any photographs of the plate assembly ?
 
ill do some photos later.. My BZ has the probe 6 cm in from the edge. my plate has a small semi circle on the outer edge that seems to serve no purpose.. looks like I have an older design plate
 
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Photos IMG_1669.jpgIMG_1670.jpgIMG_1671.jpg
 
Mine is exactly the same as yours regarding the position of the probe and the notch. Maybe try rotating the plate there may be a high spot.
Mine didn't wobble until I rotated it and found a high spot.
Thanks I had a good look at it and the plate does indeed have a low spot and the fit is a tiny bit better. but not 100% flat.. worst case teh plate may get a well placed whack with a ball hammer .. I have emailed Kegland to ask if this is how it should be?
 
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Manufacturing tolerances don't seem very good.
The g4 I received had an oval shaped outer body at base. Resulting in false bottom being a good fit one way, but with 2.5mm edge gaps on other axis. BTK supplied a replacement, which was much better.

On my g4 35L, if I line up a false bottom foot, with the sensor. By pressing down, I can feel (depending on which foot) that heat plate is either around 0.5mm the sensor, or just touching it.w

Maybe your probe is projecting further up from the base than it should, or the base is distorted.
Measuring my sensor height (above base) with vernier calipers: it's 8.4mm to one side (along tangent), and 9.6mm to the other side. So my base must be deformed around where sensor is fixed (I see uneven reflections from base around there).

Rather than bending your heat plate, it might be safer to either flatten the heat plate spacer feet a little (I'd grind them down), or lever out the false bottom feet (to make them taller). Risk with the latter method, is that base could end up taking the malt pipe weight.
A probably better alternative, would be to drill a hole in the heat plate, that would clear the sensor. The sensor might work even better, with flow two ways, and you don't risk messing up the base - heat plate - false bottom - malt pipe spacings.
 
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Thanks All

I got this reply from Kegland

"Are you assembling this correctly:
The order of bolt to washer to nuts goes as follows. Eye bolt, washer, false bottom, washer, nut, HED then wing nut. This is so that the eye bolt does not come completely removed when and if you clean underneath the Heat Exchanger Dish."


Which doesnt take me forward any,

Davegase said
try rotating the plate there may be a high spot.
Mine didn't wobble until I rotated it and found a high spot.

And there is indeed a highspot in my assembly where the assembly almost sits flat. the gap between the plate and the false bottom isnt even. almost like there is a distortion from manufacture.. which for me is Peess Poor tollerances.
Having worked a metal press in the past it strikes me the pressure on the press was wrong during stamping or there has been heat distortion when welding .

However I shall try it using the high spot method and if that doesnt work Ill drill the plate to allow the probe to stand in fluid .
 

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