controlling FV temperature with solenoid valve

[Hogarth]

Sorry if I'm missing something, but would it not be easier to switch the pump on and off?

That would be great but 65L of wort fermenting at 21 degrees doesn't need a lot of chilling. The pump would go on so infrequently that I'm worried it would freeze. Am I missing something here?

I don't know ... I thought these Maxis had a variable thermostat on the reservoir that could be set to above zero. If so, you could rewire your Maxi so that the pump is controlled by the PID, and simply let the water sit around in the reservoir when it's not needed. I think a few guys on here do it like that.

[themadhippy]

would require some sort of simple logic circuitry to make two behave as a single 3-way one so the cheapness has some hidden costs in effort and money.

simplest way would be a DPDT relay with the coil controlledby the pid.

[Kev888]

Yes, I'd imagine you could get away with a SPDT to just change over between one FV and one recirc valve, but with a number of FV valves I could probably chain the second poles of DPDT relays in series to make an 'and' setup, so only if all the FV valves are off will the recirc valve will be on.

Cheers
Kev

[Deller12]

Sorry if I'm missing something, but would it not be easier to switch the pump on and off?

That would be great but 65L of wort fermenting at 21 degrees doesn't need a lot of chilling. The pump would go on so infrequently that I'm worried it would freeze. Am I missing something here?

why not use a central heating 3 way valve.

Can you point me in the right direction?

Edit: you mean like this? http://m.screwfix.com/p/siemens-cmv322- ... alve/45944

How quickly does it switch?

Edit2: seems like there are two types; mid position and diverter. Spring return 3 way diverter seems to be the correct type for this system. Drawbacks are price and the fact that they are only rated down to 5 degrees.

Nice set up mike

I am working on the same set up as you but i have made a stainless coild from 3\8 stainless tubing to sit inside the conical see pic below.What are you main concerns here keeping the beer warm or cooling it ?


I am looking to weld this coil in as soon as my next brew is out of the conical. As my fermenter is sat in the garage my main issue is keeping it warm. I am looking to use a 5 gallon plastic fermenting bin and aquarium heater to warm the water in the plastic bin to around 35 degrees. I will then set the PID to kick the pump on and off and send warm water round the coil to maintain my fermenting temperature. I am sure this will work during the winter but I will need a re think in the summer to cool the fermenting beer.

Lee

[MikeMarcus]

Hi Lee.

Keeping it warm is easy. A brewbelt or two connected to a temp controller is the simplest way to do the job. I'm concerned with cooling, both for brewing ales during the summer and lager production.

I thought these Maxis had a variable thermostat on the reservoir that could be set to above zero. If so, you could rewire your Maxi so that the pump is controlled by the PID, and simply let the water sit around in the reservoir when it's not needed. I think a few guys on here do it like that.

I was under the impression that the python pump/agitator was necessary to prevent the reservoir freezing. I know that some models of Maxi have variable thermostats on the front panel, mine is not one of them unfortunately. Reading around, I know that other people have had issues with their python pumps or return pipes freezing using this method of control. If anyone can shed light on this issue, I would love to know more.

Run glycol in it maybe?

I have read two different reasons why you can't run glycol in a maxi. One is that the python pump is not designed for liquids with such viscosity, the other is that the lack of ice causes the thermostat to malfunction which puts too much load on the compressor. Again, if anyone is able to provide more information on this, I would love an explanation.

Apart from my own project, this forum could really do with a definitive reference for the best way to control Maxi's and similar chillers. I know that there has been some talk on the subject before but not really any resolution.

[MikeMarcus]

Aha! I found a suitable part on eBay.



http://www.ebay.co.uk/itm/251146015250

It's a bit pricey though.

Edit: I spoke to the supplier and they said that it is meant to operate with mineral oil. Water would cause it to rust. Arse!

[Deller12]

Hi Lee.

Keeping it warm is easy. A brewbelt or two connected to a temp controller is the simplest way to do the job. I'm concerned with cooling, both for brewing ales during the summer and lager production.

I thought these Maxis had a variable thermostat on the reservoir that could be set to above zero. If so, you could rewire your Maxi so that the pump is controlled by the PID, and simply let the water sit around in the reservoir when it's not needed. I think a few guys on here do it like that.

I was under the impression that the python pump/agitator was necessary to prevent the reservoir freezing. I know that some models of Maxi have variable thermostats on the front panel, mine is not one of them unfortunately. Reading around, I know that other people have had issues with their python pumps or return pipes freezing using this method of control. If anyone can shed light on this issue, I would love to know more.
Mike a daft question bit have you considered fitting a separate PID to you cooler to set the tempreture.

Run glycol in it maybe?

I have read two different reasons why you can't run glycol in a maxi. One is that the python pump is not designed for liquids with such viscosity, the other is that the lack of ice causes the thermostat to malfunction which puts too much load on the compressor. Again, if anyone is able to provide more information on this, I would love an explanation.

Apart from my own project, this forum could really do with a definitive reference for the best way to control Maxi's and similar chillers. I know that there has been some talk on the subject before but not really any resolution.

[Deller12]

Hi Lee.

Keeping it warm is easy. A brewbelt or two connected to a temp controller is the simplest way to do the job. I'm concerned with cooling, both for brewing ales during the summer and lager production.

I thought these Maxis had a variable thermostat on the reservoir that could be set to above zero. If so, you could rewire your Maxi so that the pump is controlled by the PID, and simply let the water sit around in the reservoir when it's not needed. I think a few guys on here do it like that.

I was under the impression that the python pump/agitator was necessary to prevent the reservoir freezing. I know that some models of Maxi have variable thermostats on the front panel, mine is not one of them unfortunately. Reading around, I know that other people have had issues with their python pumps or return pipes freezing using this method of control. If anyone can shed light on this issue, I would love to know more.
Mike a daft question bit have you considered fitting a separate PID to you cooler to set the tempreture.

Run glycol in it maybe?

Daft question but have you conciderd using a PID on the maxi unit i have fitted one to mine it works a treat
I have read two different reasons why you can't run glycol in a maxi. One is that the python pump is not designed for liquids with such viscosity, the other is that the lack of ice causes the thermostat to malfunction which puts too much load on the compressor. Again, if anyone is able to provide more information on this, I would love an explanation.

Apart from my own project, this forum could really do with a definitive reference for the best way to control Maxi's and similar chillers. I know that there has been some talk on the subject before but not really any resolution.

[MikeMarcus]

Bingo! After 2 days of research I have found a solution which will work. The following parts are needed:

• SMC VX3244-03F-JDR1 solenoid from Brammer (telephone number 0870 2402100/ 5 week lead time)
• 3 x John Guest part number PI011213S

It's likely to cost about 70 quid though

[Fil]

ouch..

i would be looking at cheaper 2 valve options.. perhaps look at ac 240v solutions, w/machine and dishwasher input valves have large ports, and are cheap... the pid alarm relays may handle 240v with low amp demands?

i have a chiller with a controller, it has an agitator, the controller sets the speed of the agitator, not the temperature of the ice bath, less agitation, less effective chiling... a still waterbath will chill less than an agitated bath due to the 'warm pocket effect'. the pump or agitator ensure that the tightly wound product coils get cold water moving over thier surface for optimum cooling..

also I am not speaking from any authoruty beyond observation, But i think the sensor that detects the ice wall is a pressure sensor, as emmbedded in 6mm of ice is the same temp as embedded in 30mm of ice, however the pressure is different.. and the chillers build up an ice wall of a certain thickness regardless of agitation or python pumping... and if you look in the icebath the sensor attached to the compressor controller is tied onto the chilling pipes which will contain coolant at less than 0C when running???????
(based on the experience of an ebay bargain with a dodgy controller which was fixed by bypassing the agitator control.. without an agitator running the compressor cut out when the ice wall was a couple of inches thick, the same as when the agitator control was bypassed )


while the 3way valve is an elegant solution, perhaps its overkill. and just use the python pump on/off, as determined by your wort temp?

test it disconnect the python and fire up the chiller and see if the icewall builds up any thicker? i think somehow it wont be any different

[MikeMarcus]

In that case I'm taking the easy route and wiring the PID up to the python pump. Thanks for the information.

[Fil]

please give your chiller a pumpless test to ensure the compressor cuts out without freezing it solid first

that chiller looks like new, unlike the rusty ol box i had a poke about inside of.. So dont commit on the basis of my observations of an ebay bargain chiller that needed a hack to get it "working properly".. give a better
authority the opportunity to shoot me down first..

[MikeMarcus]

that's OK. I have just spent the last couple of hours wiring it up in a reversible manner. I was very lucky to find a new chiller on ebay at second hand prices.

[MikeMarcus]

that's OK. I have just spent the last couple of hours wiring it up in a reversible manner. I was very lucky to find a new chiller on ebay at second hand prices.

[Deller12]

Hi Guys,

I finished my keeping the conical warm project it works a treat As soon as the warmer weather arrives I will swap over to the maxi cooler to cool the conical. A few picture below for anyone who is interested.


Cheers

Lee