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Date: 09 Nov 2006 14:43:29
From: robert Harmon
Subject: excess heat build up & PID
Even with the aluminum enclosure for the PID the heat builds up in the PID
installed inside my Bunn ES-1A. While it is well within the Watlow's
operating parameters, I'm concerned for it's long term well being.

I've decided not to use a fan & ducting, but instead try a Peltier module.
Used in conjunction with an appropriately sized heat sink, I'm convinced
this will be the best way to control heat & extend the life of the
controller.

Any thoughts on this?

Robert (Be cool!) Harmon

--
http://tinyurl.com/pou2y
http://tinyurl.com/fkd6r
Remove "Z" to reply via email.




 
Date: 09 Nov 2006 10:58:33
From: daveb
Subject: excess heat & moist
mmmmmmmmm, hot and moist!

[ :-) ]

Dave

Jack Denver wrote:
> Much simpler and better to move the controller outside the main enclosure
> of the machine - on top of the cup warmer, hanging from the side, under the
> drip tray - anywhere but inside where it is hot and moist.
>
>



 
Date: 09 Nov 2006 13:31:22
From: Jack Denver
Subject: Re: excess heat build up & PID
Much simpler and better to move the controller outside the main enclosure
of the machine - on top of the cup warmer, hanging from the side, under the
drip tray - anywhere but inside where it is hot and moist.



"robert Harmon" <r_h_harmon@Zhotmail.com > wrote in message
news:Xns987658C2F1156rhharmonZhotmailcom@207.217.125.201...
> Even with the aluminum enclosure for the PID the heat builds up in the PID
> installed inside my Bunn ES-1A. While it is well within the Watlow's
> operating parameters, I'm concerned for it's long term well being.
>
> I've decided not to use a fan & ducting, but instead try a Peltier module.
> Used in conjunction with an appropriately sized heat sink, I'm convinced
> this will be the best way to control heat & extend the life of the
> controller.
>
> Any thoughts on this?
>
> Robert (Be cool!) Harmon
>
> --
> http://tinyurl.com/pou2y
> http://tinyurl.com/fkd6r
> Remove "Z" to reply via email.




 
Date: 09 Nov 2006 10:05:11
From: daveb
Subject: Re: excess heat build up & PID
Good point, Ian!

lash it to the side with Velcro!

I- >Ian wrote:
> On Thu, 09 Nov 2006 16:33:03 GMT, Barry Jarrett
> <barry@rileys-coffee.com> wrote:
>
> >
> >put a fan on it.
> pulling in outside air
>
> If the fan is inside the box, blowing 140F air on it will keep it at
> 140F.
>
> To cool, there must be a temperature differential.



  
Date: 09 Nov 2006 18:09:19
From: I->Ian
Subject: Re: excess heat build up & PID
On 9 Nov 2006 10:05:11 -0800, "daveb" <davebobblane@gmail.com > wrote:

>lash it to the side with Velcro!

bits of string would have more cachet


 
Date: 09 Nov 2006 16:33:03
From: Barry Jarrett
Subject: Re: excess heat build up & PID

put a fan on it.



  
Date: 09 Nov 2006 16:40:18
From: I->Ian
Subject: Re: excess heat build up & PID
On Thu, 09 Nov 2006 16:33:03 GMT, Barry Jarrett
<barry@rileys-coffee.com > wrote:

>
>put a fan on it.
pulling in outside air

If the fan is inside the box, blowing 140F air on it will keep it at
140F.

To cool, there must be a temperature differential.


 
Date: 09 Nov 2006 08:53:55
From: Ken Fox
Subject: Re: excess heat build up & PID
"robert Harmon" <r_h_harmon@Zhotmail.com > wrote in message
news:Xns987658C2F1156rhharmonZhotmailcom@207.217.125.201...
> Even with the aluminum enclosure for the PID the heat builds up in the PID
> installed inside my Bunn ES-1A. While it is well within the Watlow's
> operating parameters, I'm concerned for it's long term well being.
>
> I've decided not to use a fan & ducting, but instead try a Peltier module.
> Used in conjunction with an appropriately sized heat sink, I'm convinced
> this will be the best way to control heat & extend the life of the
> controller.
>
> Any thoughts on this?
>
> Robert (Be cool!) Harmon
>
> --
> http://tinyurl.com/pou2y
> http://tinyurl.com/fkd6r
> Remove "Z" to reply via email.

How do you know that heat is building up in the enclosure?

The PID controller itself is unlikely to create much heat, however it can
certainly be exposed to heat from say, the boiler, the group, or other
operating components inside an espresso machine. Although potentially more
"elegant" in appearance, inside-the-machine installs are probably to be
avoided for this reason, plus the informal observations Barry Jarrett has
previously posted, wherein an unventilated PID controller can behave
erratically compared to one that is exposed to airflow. This is because
there is a "reference junction" inside the controller itself which is used,
as implied, as a temperature reference.

For this reason I have chosen on both of my installations to mount the PID
in an aluminum project box, with holes drilled in it, attached to the
underside of my machines, under the watertight electronics box under the
driptray. They are not exposed to any significant heat this way, no more
than ambient room temperature. Each machine has a different design, and
hence needs a somewhat different placement for an external box, with
attention to such risks as spill accidents and avoiding gravity waterflow
into the PID box as a result, plus avoiding wet locations for other obvious
reasons such as avoiding electrical shocks and damage to the controller
itself.

ken




  
Date: 09 Nov 2006 16:27:07
From: I->Ian
Subject: Re: excess heat build up & PID
On Thu, 9 Nov 2006 08:53:55 -0700, "Ken Fox"
<morceaudemerdeThisMerdeGoes@hotmail.com > wrote:

>"robert Harmon" <r_h_harmon@Zhotmail.com> wrote in message
>news:Xns987658C2F1156rhharmonZhotmailcom@207.217.125.201...
>> Even with the aluminum enclosure for the PID the heat builds up in the PID
>> installed inside my Bunn ES-1A. While it is well within the Watlow's
>> operating parameters, I'm concerned for it's long term well being.
>>
>> I've decided not to use a fan & ducting, but instead try a Peltier module.
>> Used in conjunction with an appropriately sized heat sink, I'm convinced
>> this will be the best way to control heat & extend the life of the
>> controller.
>>
>> Any thoughts on this?
>>
>> Robert (Be cool!) Harmon
>>
>> --
>> http://tinyurl.com/pou2y
>> http://tinyurl.com/fkd6r
>> Remove "Z" to reply via email.
>
>How do you know that heat is building up in the enclosure?
>
>The PID controller itself is unlikely to create much heat, however it can
>certainly be exposed to heat from say, the boiler, the group, or other
>operating components inside an espresso machine. Although potentially more
>"elegant" in appearance, inside-the-machine installs are probably to be
>avoided for this reason, plus the informal observations Barry Jarrett has
>previously posted, wherein an unventilated PID controller can behave
>erratically compared to one that is exposed to airflow. This is because
>there is a "reference junction" inside the controller itself which is used,
>as implied, as a temperature reference.
>
>For this reason I have chosen on both of my installations to mount the PID
>in an aluminum project box, with holes drilled in it, attached to the
>underside of my machines, under the watertight electronics box under the
>driptray. They are not exposed to any significant heat this way, no more
>than ambient room temperature. Each machine has a different design, and
>hence needs a somewhat different placement for an external box, with
>attention to such risks as spill accidents and avoiding gravity waterflow
>into the PID box as a result, plus avoiding wet locations for other obvious
>reasons such as avoiding electrical shocks and damage to the controller
>itself.
>
>ken
>

Ditto, but cooling slots milled in bottom and sides on a Bridgeport.



 
Date: 09 Nov 2006 07:51:39
From: bk
Subject: Re: excess heat build up & PID
condensation. You can easily cool it below the ambient temp. And
you'll need to dump the heat from the heatsink somewhere, so a small
fan might be a lot simpler(TECs can consume up to twice the power they
dissapate) otherwise its a novel use for one, never heard of one in
a coffee maker yet.

-bradk


robert Harmon wrote:
> Even with the aluminum enclosure for the PID the heat builds up in the PID
> installed inside my Bunn ES-1A. While it is well within the Watlow's
> operating parameters, I'm concerned for it's long term well being.
>
> I've decided not to use a fan & ducting, but instead try a Peltier module.
> Used in conjunction with an appropriately sized heat sink, I'm convinced
> this will be the best way to control heat & extend the life of the
> controller.
>
> Any thoughts on this?
>
> Robert (Be cool!) Harmon
>
> --
> http://tinyurl.com/pou2y
> http://tinyurl.com/fkd6r
> Remove "Z" to reply via email.