Help with Triple Aquastat wired incorrectly to Thermostat

Reply

  #1  
Old 10-19-15, 04:18 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Help with Triple Aquastat wired incorrectly to Thermostat

Hi Everyone,

I have been searching high and low for a simple explanation of how to wire a Honeywell Triple Aquastat L8124E to a Honeywell RTH6580WF thermostat. I am pretty sure that the "plumber" I had install them did it incorrectly. He fried the transformer and installed a new one, which seems to work properly. Anyway, the only thing I can control with the thermostat is whether the boiler turns on or off. To turn it on, I have to set the fan to on. To turn it off, I have to set the fan to auto. I have looked at the wiring and it's as follows:

G from the thermostat goes to TV on the aquastat.
C from the thermostat goes to Z on the aquastat.
RC (has a jumper to R) goes to R on the transformer
C from the transformer goes back up and ties into the wire connection G to TV above.


Any help would be greatly appreciated.
 
Sponsored Links
  #2  
Old 10-19-15, 04:40 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
Welcome to the forums.

The diagram illustrates the terminals to be connected. The R jumper should be in place.
Not sure why the guy even used green ?

Name:  L8124__E.JPG
Views: 5030
Size:  41.0 KB
 
  #3  
Old 10-19-15, 05:14 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Thanks PJmax. So if I'm understanding this correctly, from the thermostat R goes to TV, W goes to T, and C goes to Z?
 
  #4  
Old 10-20-15, 05:10 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Yes...

And there is no reason for him to have used the G terminal.

The R to Rc jumper stays in place with an exception; if you are also using this t'stat to control an A/C unit. Are you? If so perhaps some rethinking is in order.
 
  #5  
Old 10-20-15, 09:00 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Thanks, NJT. I am not runnin A/C. I'll rewire when I get home tonight.
 
  #6  
Old 10-20-15, 03:18 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
The only thing I'm confused about is the R coming from the transformer. Right now it goes to the R on the thermostat. Is this necessary? If I run the R on the thermostat to the TV on the aquastat nothing will be connected to the R on the transformer.
 
  #7  
Old 10-20-15, 03:33 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Is this necessary?
You NEED a "C" wire.

If I run the R on the thermostat to the TV on the aquastat nothing will be connected to the R on the transformer.
What transformer are you talking about?

He fried the transformer
I'm afraid you have not told us everything.

Do you have multiple zones? i.e. Electric zone valves?

If this is the case STOP where you are and tell us the whole story.
 
  #8  
Old 10-20-15, 04:14 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
I do not have multiple zones.

The guy fried the transformer that is built into the aquastat. So he took it off and replaced it with a new transformer. The new transformer has both a C and an R on it. The C coming out of the transformer is tied into the wire going from Z on the aquastat to C on the thermostat. The R coming out of the transformer goes to Rc on the thermostat (which has the jumper to R still attached). So if I disconnect R on the transformer and move it to TV on the aquastat ( what the diagram shows I should do) nothing will be connected to the R on the transformer.

I'll just move the wire that's connected to G on the thermostat over to W and connect the other end to T on the aquastat.
 
  #9  
Old 10-20-15, 04:22 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
It doesn't matter what the transformer is actually labeled. It is still connected as shown in the diagram. The two transformer leads should be on Z and TV. The pink leads are representing the transformer wires.

If not...we may need a picture of how it's connected.

Name:  L8124__E_MOD.JPG
Views: 945
Size:  41.0 KB
 
  #10  
Old 10-20-15, 04:38 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
I'll just move the wire that's connected to G on the thermostat over to W and connect the other end to T on the aquastat.
NO. Please STOP !

As Pete said, you need one wire from the transformer to Z and one wire to TV.

If you have no wire from the transformer to the TV terminal, the burner will not fire.

Then connect the thermostat as shown.

The C and R on the transformer are IRRELEVANT. It does not matter what they are labeled.
 
  #11  
Old 10-20-15, 05:01 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Okay. So I spliced one lead from the transformer to the wire running from TV to R. The other lead is spliced to the wire running from Z to C. I'm connected a wire from T to W. When I turn the power on the boiler starts up but the thermostat doesn't seem to control it at all. The thermostat does have power.
 
  #12  
Old 10-20-15, 05:37 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
If the boiler needs to maintain temperature..... it will run until it hits the low temp cutoff.
If it's a cold start boiler.... different answer.
 
  #13  
Old 10-20-15, 06:21 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
I'm connected a wire from T to W.
I don't recall anyone telling you to do that.

Remove that wire.
 
  #14  
Old 10-20-15, 06:26 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
T to W is correct and is shown in my diagram.
 
  #15  
Old 10-20-15, 06:28 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
That's what the diagram says W to T.
 
  #16  
Old 10-20-15, 06:32 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Ohhhh... I see the confusion now.

I thought you meant that you put a wire from terminal T in the aquastat to terminals W in the aquastat. That would short out the transformer again if you did that.

You ran the W terminal in the THERMOSTAT to the T terminal in the aquastat.
 
  #17  
Old 10-20-15, 06:55 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
I'm not sure how to tell if it's a cold start boiler or not. I put the wires back how they were so at least I can turn the boiler on and off with the thermostat.

Here's a pretty junky diagram of how it's wired now. As I said, I can turn the boiler on by setting the fan to ON on the thermostat. I can turn the boiler off by setting the fan to AUTO on the thermostat.
Name:  FullSizeRender-2.jpg
Views: 546
Size:  29.5 KB
 
  #18  
Old 10-20-15, 07:19 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
And this is how I hooked it up following the diagram and both of your advice.Name:  IMG_9935.jpg
Views: 565
Size:  22.7 KB
 
  #19  
Old 10-20-15, 07:58 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
The way we told you to wire it should be correct.

Does the boiler normally stay hot even when there is no call for heat ? That's a warm start.
Does the boiler normally stay cold until the thermostat calls for heat ? That's a cold start.

If the boiler gives you domestic hot water.... it's a warm start.


The wiring is very simple. When you short TV to T..... you should get heat.

The two transformer wires only go to TV and Z correct ? They don't connect anywhere else ?
 
  #20  
Old 10-21-15, 09:26 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
The boiler is a cold start, then. The transformer leads do not connect directly to the Z and TV leads on the aquastat, but rather are spliced into the wires connecting the aquastat and thermostat.
 
  #21  
Old 10-21-15, 09:28 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
The boiler is a cold start
Not with an 8124E aquastat it's not.
 
  #22  
Old 10-21-15, 09:33 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
I'm not sure what you mean by "short TV to T".
 
  #23  
Old 10-21-15, 09:58 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Here's a pic. I can't seem to find any info on it. Name:  IMG_9834.jpg
Views: 556
Size:  52.4 KB
 
  #24  
Old 10-21-15, 10:04 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
Could it be that the boiler is a warm start and what I need to do is lower the low temp cutoff on the aquastat? Right now the hi is 180 and the low is 160. the low diff is 20.

Like PJMax said, once it reaches the low temp cutoff, the boiler will cycle off until the thermostat calls for heat?

Sorry to be such an idiot with this stuff.
 
  #25  
Old 10-21-15, 10:18 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
Look at the drawing. Your thermostat creates a short between the R(TV) and W(T) to start the heating process.


Name:  L8124__E_MOD.JPG
Views: 712
Size:  31.0 KB


The cycling should be the exact same with both stats. You said when the new stat is connected and you turn it on..... the boiler runs. When you connect it the old way and turn it on... the boiler doesn't run. That part doesn't make sense. This is what has us confused.
 
  #26  
Old 10-21-15, 11:49 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
No that's wrong. When I connect it the old way, I can cycle the boiler on and off using the thermostat (but I have no actual temperature control. Just On/Off). When I connect it the new way, as soon as I turn the power back on the boiler cycles on, but the thermostat no longer seems to have any control.
 
  #27  
Old 10-21-15, 01:22 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
No that's wrong
No, it's not. That's the way it SHOULD work.


I think your guy trashed your thermostat when he smoked the transformer.
 

Last edited by NJT; 10-21-15 at 07:16 PM.
  #28  
Old 10-21-15, 06:23 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
Ahhhh...... to add to that. Maybe you're right. The relay for W is welded on. That makes perfect sense.

If you have an ohmmeter you can check from R to W. It should show no continuity when stat is off (no heat or cool set) or when not calling for heat.

Must be checked with no wires connected to stat.
 
  #29  
Old 10-22-15, 05:44 AM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
I don't have an ohm meter. I ordered a new thermostat that should arrive Friday. I really appreciate all your advice. I'll let you know if that does it.
 
  #30  
Old 10-22-15, 11:24 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,079
Received 1,110 Votes on 1,030 Posts
You've come a far way and should be learning with this experience. You'll find that a test meter can be an invaluable piece of equipment. You can pick up something as basic as one from the depot for around $15.00. Start with a basic analog meter..

Name:  depot_analog.jpg
Views: 542
Size:  36.9 KB
 
  #31  
Old 10-26-15, 04:30 PM
N
Member
Thread Starter
Join Date: Oct 2015
Posts: 16
Received 0 Votes on 0 Posts
You both have been super helpful. I just hooked up the new thermostat and bang! Everything works perfectly! So the guy did fry the thermostat along with the transformer.

Thanks so much for all of your help!
 
  #32  
Old 10-26-15, 06:50 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Awesome!

Send him the bill...
 
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
 
Ask a Question
Question Title:
Description:
Your question will be posted in: