Setting up a dx milk tank?

[Scoffcruddle]

Evening all,I've bought a new to me dx milk tank and need to do as much install work as possible,what's the best way of setting the levels?

Is it just a case of spirit level on the top and adjust the legs?:rolleyes:

Also it's got twin compressors and they seem to be huge,sticker on one is a copeland san2 v9 zr 12ME TWD,by my detective work these are 10hp each.

It's not a huge tank only 8400litres,would large compressors be for every day collection?

Cheers Scoff.

[chemi-cool]

What is the make?
Post a picture and I will help you, have installed many of these.

[Scoffcruddle]

What is the make?
Post a picture and I will help you, have installed many of these.

Thanks,It's a packo tank (1999)

[chemi-cool]

Place a spirit level under the front side, it should be level from left to right side.
slope should be 2%,means 2 cm per meter of lengths - assume it is 4 meters long, difference in height from front to back should be 8 cm.

Two10 hp compressors are too big in capacity, I think only one work at a time,

Can you please get a picture of the back of the tank and the condensing unit?

[Scoffcruddle]

Place a spirit level under the front side, it should be level from left to right side.
slope should be 2%,means 2 cm per meter of lengths - assume it is 4 meters long, difference in height from front to back should be 8 cm.

Two10 hp compressors are too big in capacity, I think only one work at a time,


Can you please get a picture of the back of the tank and the condensing unit?

I'll get some pics tomorrow.(y)

Thanks for the setting up info.��

[monkey spanners]

Its probably an everyday tank with no precooling, the data plate should show the cooling class 4BII for four milkings, 2BII for two milkings.

To level it you need two trolley jacks, start with all the legs fully wound up, you need to decide which end needs to go up to get the fall correct and put a jack in the center at that end and raise it off the ground, then with the other jack, lift whichever corner that needs to go up until the level is correct then wind the leg down in that corner and remove the jack, re check the level. Usually level them across the manhole, lid open and seal removed, but re check on across the bottom if its a flat bottom tank, stand back and see if it looks right sometimes they are not as accurately welded together as you would think.
For the fall, i think there should be two pins on the top of the tank, put your level on there, personally I would jack it up until the bubble is just touching the line so its almost too steep, have had problems putting them in to factor fall and the milk doesn't flow out quick enough for modern tankers, after three air in the line alarms they stop filling and there can still be milk in the tank.

Heres a vid of an older style tank being leveled, the level points are different but the principles are the same,

https://www.youtube.com/watch?v=iOyjNKVyxzs

[Scoffcruddle]

Its probably an everyday tank with no precooling, the data plate should show the cooling class 4BII for four milkings, 2BII for two milkings.

To level it you need two trolley jacks, start with all the legs fully wound up, you need to decide which end needs to go up to get the fall correct and put a jack in the center at that end and raise it off the ground, then with the other jack, lift whichever corner that needs to go up until the level is correct then wind the leg down in that corner and remove the jack, re check the level. Usually level them across the manhole, lid open and seal removed, but re check on across the bottom if its a flat bottom tank, stand back and see if it looks right sometimes they are not as accurately welded together as you would think.
For the fall, i think there should be two pins on the top of the tank, put your level on there, personally I would jack it up until the bubble is just touching the line so its almost too steep, have had problems putting them in to factor fall and the milk doesn't flow out quick enough for modern tankers, after three air in the line alarms they stop filling and there can still be milk in the tank.

Heres a vid of an older style tank being leveled, the level points are different but the principles are the same,

https://www.youtube.com/watch?v=iOyjNKVyxzs

Just had a look and it is a 2bII

One of the compressors isn't in great shape14146

14147

I have a mains fed plate cooler and also a tube cooler from an ice bank so the tank should be doing minimal cooling,would I get away with just one compressor?

Sorry @chemi-cool forgot to take a pic of the tank.

[chemi-cool]

Are you sure these units was connected to the tank?
There should be an accumulator as well to protect the compressor from liquid floodback.

from my experience, two 5 hp units are the maximum for 8 ton milk tank.

If in doubt, contact Packo and ask them for the condensing units capacity, just give them the serial number.

Have you seen this tank running with these units?

[monkey spanners]

Are you sure these units was connected to the tank?
There should be an accumulator as well to protect the compressor from liquid floodback.

from my experience, two 5 hp units are the maximum for 8 ton milk tank.

If in doubt, contact Packo and ask them for the condensing units capacity, just give them the serial number.

Have you seen this tank running with these units?


I have a customer with a 6750L De Laval tank and that has two 10hp units on it, its oversized for the farm its on now as they have an icebuilder but i suspect the original place had no precooling hence the big units.

None of the units here have accumulators on, (except the old fixed orifice Fabdec tanks), though years ago I used to occasionally fit Surge tanks that were imported from the USA and they had accumulators, maybe the specifications vary according to the country.

[chemi-cool]

I have a customer with a 6750L De Laval tank and that has two 10hp units on it, its oversized for the farm its on now as they have an icebuilder but i suspect the original place had no precooling hence the big units.

None of the units here have accumulators on, (except the old fixed orifice Fabdec tanks), though years ago I used to occasionally fit Surge tanks that were imported from the USA and they had accumulators, maybe the specifications vary according to the country.

That is strange, Only if you use TEV it can work but even then, compressors will starve.
Evaporator size, roughly is one square meter per horse power.
I have serviced Bigger packo tanks over here and they have a problem with double the usual power and high ambient.
If that is the case,then its a big waste of energy.

[Magoo]

Hi all.
interesting post and replies, here in NZ we do milk in large amounts, for the life on me I have never come across a square milk vat, generally here they are round and large from 3000 lt to 30000 litres and multiples of at the farms, all with pre coolers and energy recovery systems. dependent on milking herds and daily collection or second day collection. generally two milkings a day.
Then there is the processing plants, massive refrigeration equipement through out country.

[Scoffcruddle]

Are you sure these units was connected to the tank?
There should be an accumulator as well to protect the compressor from liquid floodback.

from my experience, two 5 hp units are the maximum for 8 ton milk tank.

If in doubt, contact Packo and ask them for the condensing units capacity, just give them the serial number.

Have you seen this tank running with these units?

I haven't seen the compressors connected but the wiring and piping match up,I think the era this tank was from was before pre cooling and energy saving was the norm.

I'm not sure I'll have enough power for twin 10hp compressors as during milking time there is a load of extra power being used elsewhere.

I'll take a pic of the back of the tank today.

Thanks all for the replies so far.

[Scoffcruddle]

Hi all.
interesting post and replies, here in NZ we do milk in large amounts, for the life on me I have never come across a square milk vat, generally here they are round and large from 3000 lt to 30000 litres and multiples of at the farms, all with pre coolers and energy recovery systems. dependent on milking herds and daily collection or second day collection. generally two milkings a day.
Then there is the processing plants, massive refrigeration equipement through out country.

I've two square ice bank tanks that are built in the late 60s and early 70s,I've extended both upwards and they are now at their limit at 5200litres each,they have been excellent and I'm going to keep them as back up tanks a real testament of how well we could build things.

[chemi-cool]

Local manufacturer with a little help from me has developed a new approach to cooling milk in DX tanks.
All manufacturers make the evaporators along the tank operating the units at full capacity and maximum heat load
as all the evaporator is covered with hot milk. To overcome the high evaporating temps, more power is required to low it around 0C > -2C evaporation temp.
The new tanks we use have the evaporators across, fed from the bottom and suction from both sides at three quarters height. Evaporator becomes a flooded one and cooling capacity is at maximum from the beginning with low evaporation temp. In this method, a much smaller condensing unit is required and and big tanks [40 tons] can easily handle 3500 liters per hour at 38C ambient with only 6, 5HP condensing units.
That's why I was surprised at the power you use on a 8 ton tank.

[Scoffcruddle]

14152

Can this type of set up be plumbed up with one compressor?

[chemi-cool]

Can you tell me what is the TXV model and orifice size?

[Scoffcruddle]

Can you tell me what is the TXV model and orifice size?

Pipe looks like 11 maybe 12mm

Danfoss TEX2 68Z3209 it has 068-2009 No 06 on a little red cap.

[chemi-cool]

That's what i had in mind, i just don't understand how they match a 10 hp compressor with double the capacity.

One of your condensing units is just enough for the milk tank.

[monkey spanners]

What Chemi said^

Think those danfoss tev's only rated about 15kw on R22. R22 has been banned here, you will need to convert the system to use a different refrigerant also change all the rubber O rings as R22 makes them swell and they will shrink and leak once the R22 is no longer in the system.

[chemi-cool]

You can retrofit to R-438A without changing anything.

One thing that bother me though. If the tank was standing with open refrigerant pipes for a long time, oil that is still in the evaporator became acidic and might have caused holes. I advise you to to vacuum each circuit and pressure test with OFN up to 8 bar to make sure circuits are leak free.

[Scoffcruddle]

What Chemi said^

Think those danfoss tev's only rated about 15kw on R22. R22 has been banned here, you will need to convert the system to use a different refrigerant also change all the rubber O rings as R22 makes them swell and they will shrink and leak once the R22 is no longer in the system.

That was going to be my next question regarding R22 I saw a thread on here saying you have to recover the gas and replace with another,my tank was decommissioned late 2015 and the pipes were all soldered up,so moisture shouldn't be a problem but I'm surprised there isn't a sticker or it written on the tank what gas type so will presume R22.

I had my thermometer out tonight and my milk leaving the cooler was 6degrees C so the tank isn't going to overworked getting it down to 4.

[monkey spanners]

Refrigerant type is usually marked on the data plate on the tank. Also the X in TEX2 signifies R22.

Where abouts in the UK are you?

[Guner Edip Riza]

Milk coolers setup. Milk tanks and condensing unit capacities.
14154

[chemi-cool]

Milk coolers setup. Milk tanks and condensing unit capacities.
14154

Which company issue that info?

[Scoffcruddle]

Refrigerant type is usually marked on the data plate on the tank. Also the X in TEX2 signifies R22.

Where abouts in the UK are you?

Up in lancs,do you have a twin up in this area,we need someone decent up here.

[Scoffcruddle]

Milk coolers setup. Milk tanks and condensing unit capacities.
14154

Thanks (y)