Wiring a Jensen Wood Fired Boiler w/oil boiler backup

Reply

  #1  
Old 11-18-08, 05:00 PM
Member
Thread Starter
Join Date: Nov 2008
Location: CT.
Posts: 2
Received 0 Votes on 0 Posts
Question Wiring a Jensen Wood Fired Boiler w/oil boiler backup

This is a 1980's wood fired boiler. I want to wire this boiler to run with my existing furnace. THIS IS NOT GOING TO BE A STAND ALONE APPLICATION. I have piped it to run parallel with the oil unit. I added the second circulating pump in between the two units. There are three zones in my house run with zone valves. I want to use one of the zones for a "DUMP" zone. The wood boiler has a dual aquastat (Honeywell L4081B) with a fan control above the aquastat. My question is can I use this aquastat to run the second circulating pump, open the dump zone valve and the draft control fan? Everything I read says the aquastat opens a zone valve or runs a circulating pump but not both. Do I run the circulating pump with the 1st circulating pump on the oil burner? This can't be that complicated. Please help!! It is cold out.
 
Sponsored Links
  #2  
Old 11-18-08, 09:20 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Any chance that you have the manual for the Jensen ?

The circulator for the Jensen should run whenever there is a fire going. The fan control should regulate the temp in the Jensen by controlling the fan. The 4081 _might_ be intended to run the 'wild zone' ... but I suspect it may be intended for circulator control ... it could be wired up to sense the fire ... and turn on the circulator.

The HIGH limit doesn't seem like much use to me in this application though ... that switch BREAKS on high limit ... if it were to MAKE on high limit, you could use that to run the wild zone ... but it don't, so you can't ... unless you wire another relay ...

You don't want the wood circ pump to run with the boiler circ pump... you only want the boiler circ pump running when there is a heat call ... the wood pump runs whenever the woody is hot ...
 
  #3  
Old 11-19-08, 08:33 AM
Member
Thread Starter
Join Date: Nov 2008
Location: CT.
Posts: 2
Received 0 Votes on 0 Posts
Question Wiring a Jensen Wood Boiler

I do have the manual for the Jensen. I was confused because I didn't think the Jensen circ pump needed to run all the time. The wiring diagram is somewhat confusing to me. The 4081B, according to the manual, runs the draft control fan on the high side(shutting it off when the contacts break) and the designated dump zone valve when the contacts close on the low side. This seems to be the way it was hooked up with the previous owner, because there is a short piece if thermostat wire coming off the low side of the 4081B connected to the terminals R and W. If you say the Jensen circ pump should be running whenever there is a fire, I just need to put it on a separate switch. One other thing. I have the Jensen circ pump between the boilers on the return side. The existing oil circ pump is in the return side before the oil boiler. Should I move the oil circ pump to the supply side of the oil boiler above the Tee from the Jensen or will it circulate between the two with both of them in the returns.
 
  #4  
Old 11-19-08, 08:02 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Would you know if the manual is available on-line ? what's the model of your boiler ?
 
  #5  
Old 12-15-08, 05:12 AM
Member
Join Date: Dec 2008
Location: New England
Posts: 2
Received 0 Votes on 0 Posts
Aquastat question

What is the "exact" replacement for the Honeywell Dual L4081B-1104 Aquastat that came with my boiler. It looks like the 1104 model isn't available and I need a replacement.
 
  #6  
Old 12-15-08, 07:45 AM
Join Date: Aug 2006
Location: usa
Posts: 902
Received 0 Votes on 0 Posts
Is the constant circulator operation specified in the Jensen manual? Most wood boilers have the circulator controlled by a triple acquastat. Boiler return temps are just as critical in wood boilers as oil fired.
 
  #7  
Old 12-15-08, 01:21 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Don, Honey calls this one a "functional replacement"

L4081B-1096
 
  #8  
Old 12-15-08, 01:32 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Pete, the ones I've looked at over the past few months have all had an aquastat turning the circ pump between the woody and the oiler on when the woody hits a certain temp ...

So, presumably, that pump would also shut off when it got below the setpoint - diff ...

Then there's the high limit that might shut off the combustion air, or stop a combustion air blower ... and then the 'wild zone' control ...
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
 
Ask a Question
Question Title:
Description:
Your question will be posted in: