Outdoor Wood Furnace Info

All-Purpose OWF Discussions => Electronics => Topic started by: jackel440 on September 30, 2010, 06:55:20 AM

Title: opinions on Ranco or Johnson controls thermostats
Post by: jackel440 on September 30, 2010, 06:55:20 AM
I am trying to decide on a controller for my furnace I am building.I am looking at the Johnson. A419.I have seen the Ranco on a few new stoves.has anyone had any problems with either one?
I know I need it to control a fan and an damper actuater.all 120 volts.
Thanks
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: jackel440 on September 30, 2010, 06:36:12 PM
Well since Willie G is on the ball.I guess I made my first post clear as mud.LOL
I am just wanting to control the boile ritself,and not the inside house furnace.
Just looking for opinions on the 2 different controllers out there.
Thanks guys
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: Scott7m on October 02, 2010, 08:28:54 PM
both are good.. 

id assume to have a dial style honey well myself, less to go wrong. 
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: Larson88 on October 03, 2010, 07:35:41 AM
 im with scott if your just looking to control the fan and solenoid i would go with a honeywell aquastat there so simple and work really well.
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: NC4AB on October 03, 2010, 08:08:00 AM
I upgraded the Honeywell Aquastat to a 2 stage RANCO on my Hardy OWB a couple of years ago and have no complaints.  All the temperatures and differentials are programmable so the Ranco gives you very good flexibilty, and I used the O-10V temperature output to log the water temperature on my PC.
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: jackel440 on October 03, 2010, 08:12:21 AM
My plan is to have a standard style honeywell aquastat as my high limit switch for my stove.I will then let the digital controller run the stove the rest of the time.I am designing in a back up system to stop a runaway stove or any other problems that may arise.
I like the finer tuning and control that a digtal unit will provide thats why I am asking.
I do agree with you that Simple is great.I just can't leave well enough alone. :bash:
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: jackel440 on October 03, 2010, 08:14:55 AM
I upgraded the Honeywell Aquastat to a 2 stage RANCO on my Hardy OWB a couple of years ago and have no complaints.  All the temperatures and differentials are programmable so the Ranco gives you very good flexibilty, and I used the O-10V temperature output to log the water temperature on my PC.
Cool I like the idea of logging the water temp on the computer!You could really see what it's doing while your away.
How did you do that?What kind of cable did you run out to the boiler to feed the signal to the computer?I never thought of that.I will have to incorporate this into my stove I think.
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: NC4AB on October 03, 2010, 11:25:10 AM
Don't want to hijack the thread but I use a USB labjack to scale the 0-10v to a usable signal, and I also log the status of the circulation pump, damper, fan and water fill valve. 

I set the RANCO to open the damper if the water drops below 160 and closes when the water gets above 170.  If the natural draft is not enough then fan will on when the water gets to 150 and turns of at 160.

I used a thermostat wire to bring the 0-10v signal back to the LabJAck, the digital signals are on a cat 5 cable

A screen shot is shown below:

[attachment deleted by admin for space issues]
Title: Re: opinions on Ranco or Johnson controls thermostats
Post by: jackel440 on October 03, 2010, 05:34:06 PM
Don't want to hijack the thread but I use a USB labjack to scale the 0-10v to a usable signal, and I also log the status of the circulation pump, damper, fan and water fill valve. 

I set the RANCO to open the damper if the water drops below 160 and closes when the water gets above 170.  If the natural draft is not enough then fan will on when the water gets to 150 and turns of at 160.

I used a thermostat wire to bring the 0-10v signal back to the LabJAck, the digital signals are on a cat 5 cable

A screen shot is shown below:

Hi-jack away it's my thread anyways.That data logging is really cool.I would really like to get some more info on how you did that.Maybe you could be persaded to do a thread and some pics of your setup?
I would like to do that.