Jumping out a Chonotherm III

Posted by Existential Angst on October 15, 2009, 9:26 am

All --

If I wanted to bypass or jump out a chronotherm III, where the furnace is
connected to W1 and C screws, how would I do this? Jumping W1 and C does
not seem to do it.

Does this mean the III is supplying the 24 V to the control board? I
thought the 24V xformer was external, and that the III was just acting as a
switch. I know the 24 V transformer for cooling is external.

So if I wanted to bypass the III altogether, how would I do this?

--
EA

Posted by on October 15, 2009, 9:28 am

On Thu, 15 Oct 2009 09:26:23 -0400, "Existential Angst"

>All --
>If I wanted to bypass or jump out a chronotherm III, where the furnace is
>connected to W1 and C screws, how would I do this? Jumping W1 and C does
>not seem to do it.

Just jump W1 and C, then change the setpoint so it calls for
heat, and give it 5 minutes. That will 'latch' it up.

>Does this mean the III is supplying the 24 V to the control board? I
>thought the 24V xformer was external, and that the III was just acting as a
>switch. I know the 24 V transformer for cooling is external.
>So if I wanted to bypass the III altogether, how would I do this?

--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/

Paul ( pjm @ pobox . com ) - remove spaces to email me
'Some days, it's just not worth chewing through the restraints.'
'With sufficient thrust, pigs fly just fine.'
HVAC/R program for Palm PDA's
Free demo online at www.pmilligan.net/palm/
Free 'People finder' program now at www.pmilligan.net/finder.htm

Posted by Existential Angst on October 15, 2009, 11:33 am

> On Thu, 15 Oct 2009 09:26:23 -0400, "Existential Angst"

>>All --
>>If I wanted to bypass or jump out a chronotherm III, where the furnace is
>>connected to W1 and C screws, how would I do this? Jumping W1 and C does
>>not seem to do it.

> Just jump W1 and C, then change the setpoint so it calls for
> heat, and give it 5 minutes. That will 'latch' it up.

Suppose the III is kaput; or equivalently, suppose the two wires are
disconnected from from the III.
Jumping them doesn't work.
And there is no voltage at the wires when disconnected from the III, which
suggests no 24 V xformer on the controller or externally.

So I put the wires back on the III, and when calling for heat, saw 24 V on
the wires, suggesting that the III is supplying the 24 V to kick in the
controller.

So I disconnected the wires again, had the III call for heat, saw it was
indeed energizing the two terminals with 24 V.
So with the two wires still disconnected, I put a separate 24 V to them, to
kick in the furnace..

No go -- only when the wires are physically connected to the III does the
furnace kick in.

So is the 24 V from the III a "special" 24 V? What's going on?

--
EA

>>Does this mean the III is supplying the 24 V to the control board? I
>>thought the 24V xformer was external, and that the III was just acting as
>>a
>>switch. I know the 24 V transformer for cooling is external.
>>So if I wanted to bypass the III altogether, how would I do this?

> --
> Click here every day to feed an animal that needs you today !!!
> www.theanimalrescuesite.com/
> Paul ( pjm @ pobox . com ) - remove spaces to email me
> 'Some days, it's just not worth chewing through the restraints.'
> 'With sufficient thrust, pigs fly just fine.'
> HVAC/R program for Palm PDA's
> Free demo online at www.pmilligan.net/palm/
> Free 'People finder' program now at www.pmilligan.net/finder.htm

Posted by Tony Hwang on October 15, 2009, 7:29 pm

Existential Angst wrote:

>> On Thu, 15 Oct 2009 09:26:23 -0400, "Existential Angst"

>>> All --
>>> If I wanted to bypass or jump out a chronotherm III, where the furnace is
>>> connected to W1 and C screws, how would I do this? Jumping W1 and C does
>>> not seem to do it.

>> Just jump W1 and C, then change the setpoint so it calls for
>> heat, and give it 5 minutes. That will 'latch' it up.

>
> Suppose the III is kaput; or equivalently, suppose the two wires are
> disconnected from from the III.
> Jumping them doesn't work.
> And there is no voltage at the wires when disconnected from the III, which
> suggests no 24 V xformer on the controller or externally.
>
> So I put the wires back on the III, and when calling for heat, saw 24 V on
> the wires, suggesting that the III is supplying the 24 V to kick in the
> controller.
>
> So I disconnected the wires again, had the III call for heat, saw it was
> indeed energizing the two terminals with 24 V.
> So with the two wires still disconnected, I put a separate 24 V to them, to
> kick in the furnace..
>
> No go -- only when the wires are physically connected to the III does the
> furnace kick in.
>
> So is the 24 V from the III a "special" 24 V? What's going on?
>

Hmm,
You checked continuity of those two wires from 'stat to the furnace?
First thing first, Eh? BTW, 'stat is not a source of 24V AC.

Posted by Stormin Mormon on October 15, 2009, 9:35 am

"Dear Doctor. I'm sick. I tried taking asprin, but it didn't
help. I'm not going to tell you what symptoms I had. I'm not
going to tell you what I'm trying to accomplish by takeing
medicine. But, I'm going to ask you waht pills to take."

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.

All --

If I wanted to bypass or jump out a chronotherm III, where
the furnace is
connected to W1 and C screws, how would I do this? Jumping
W1 and C does
not seem to do it.

Does this mean the III is supplying the 24 V to the control
board? I
thought the 24V xformer was external, and that the III was
just acting as a
switch. I know the 24 V transformer for cooling is
external.

So if I wanted to bypass the III altogether, how would I do
this?

--
EA

Page 1 of 5 1 2 3 > last >>