Newbie Home Owner Boiler Questions - Boiler runs with no call for heat.

Reply

  #1  
Old 10-09-13, 11:49 AM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Newbie Home Owner Boiler Questions - Boiler runs with no call for heat.

My wife and I closed on our home in mid July. The previous owner was made his living servicing and installing oil heat and hot water systems, so needless to say our system is "unique" (I think). There are hang tags on the boiler stating not to drain-contains antifreeze. Also, it is a four zone system. You'll have to forgive my lack of knowledge in this area, never really had to deal much with boilers and hot water heaters in our previous apartments and condo.

Attached is a photo of our setup (separate boiler and hot water heater)Name:  Boiler + Hot Water.jpg
Views: 8129
Size:  51.4 KB.

Before we closed on the house, the previous owner told me to set the aquastat (looks like a dual mode, doesn't have a "diff" knob) with the "lo" knob always set all the way down, and the "hi" knob at the following settings (photo of current aquastat settings attached)Name:  Aquastat.jpg
Views: 5236
Size:  33.7 KB:

Summer: All the way down
Oct/Nov: 140/150
Dec/Jan/Feb: 150/160
March/April: 140/150

We had the burners serviced in August, and the tech told us that we could shut off the boiler until we need heat. Last night, I flipped the boiler on, everything appeared to fire up to temperature and be good. I tested one of the zones (upstairs, only rotary thermostat in the house) and the heat kicked on, the baseboards got hot, etc. Turned the thermostat back down, and the heat turned off as expected.

The problem now is with the 3 digital thermostats in the "off" position and the upstairs thermostat turned all the way down, the boiler will still kick on for a 2-3 minutes every hour or so.

Is this the way this should work, or should the boiler not be kicking on with no call for heat? Any help is appreciated!
 
Sponsored Links
  #2  
Old 10-09-13, 12:23 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 17,962
Received 37 Votes on 32 Posts
since you have a seperate HWH the boiler should be cold start. Right know the controls you have make it a warm start. That just wastes oil.

That control is for when the boiler has a coil built in for hot water. It may have at one time and when the owner removed it he did not change the control...

Can you post the model # of that aquastat? There my be a way to remove the low function..

Also the hi should be set to 180F. To save oil possibly 170 it can be set at..

Also what type of heat emitters in the home copper finned or cast iron?
 
  #3  
Old 10-09-13, 12:58 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Thanks Lawrosa. I'm not sure about the model of the aquastat. I know it is a honeywell. From the looks of it though, the low isn't even hooked up. Not sure if you can see in that picture, but there is no wire attached on the lo side. Is there any chance that old rotary thermostat is on the fritz and making random calls for heat, causing the boiler to fire up? The low knob at the moment is all the way down to the stop.

The heat emitters are copper finned.
 
  #4  
Old 10-09-13, 02:00 PM
Member
Join Date: Jun 2012
Posts: 917
Received 3 Votes on 3 Posts
I agree with Iawrosa with the cold start, you don't need to keep a low setting being you have a separate hot water supply. But I don't agree with 180 being the Hi.

The previous owner, if anything like me, knew exactly what temps have given him the best efficiency. Sort of like a manual outdoor reset. As long as he's not condensing.

I heat fine with 160 on the Aquastat in the dead of winter. It usually overshoots up 8 - 10 deg after a fire. Plus I bet the heat supply side up on top of the boiler is hotter then where the gauge and Aquastat sit mid way up. I bet he's got near 170+ if you measure at the pipe like my Intellicon does.

My suggestion is to follow the Hi set point, but make the boiler a cold start.
 
  #5  
Old 10-09-13, 02:06 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
tomf63 - Just looking at the aquastat, it would appear that the lo is disabled. Do you think there should be a wire connected to the terminal by the "lo" knob?

Thanks again!
 
  #6  
Old 10-09-13, 02:15 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
That aquastat is an L4081 model... and was probably originally set up to run the circulator off the 'low' side of it.

As you say, there is NO WIRE connected to the LOW side, so it is clear that there have been some modifications done by the P.O. of the home, and it is NOT controlling the Low limit...

What MIGHT be the case though is that the boiler is set up such that the HIGH limit is keeping the boiler hot all the time, and that the thermostat is merely turning the circulator on and off.

I see at least two more Honeywell boxes on the side of the boiler and one appears to have thermostat wire into it.

We need more information... we need to see the big picture and not focus on the aquastat...

What are the other Honeywell controls connected to?
 
  #7  
Old 10-09-13, 02:22 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
NJ Trooper, when I get home I'll snap some photos of the other Honeywell boxes.

I guess my big question would be is this setup bad or wrong in some way?
 
  #8  
Old 10-09-13, 03:30 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
We can't really judge about bad or wrong until we can figure out how it's being controlled.

From what I can see there are two 'zones', and this means that you probably have two thermostats in the home, is that right?

Both those boxes on the side of the boiler are probably going to be the same. These are most likely the relays that control the pumps, with a thermostat connected to each.

We'll have more questions later...
 
  #9  
Old 10-09-13, 04:04 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Those two boxes are the same and they do appear to go to the circulator pumps. We do however have 4 zones and 4 thermostats.
 
  #10  
Old 10-09-13, 04:23 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
If you have 4 zones then there are still some items that aren't shown in the pics.

If there are only those 2 pumps, and each pipe splits into two (can see in pics), there must be ZONE VALVES somewhere on the piping to each zone.

Thermostats will be wired to the zone valves, zone valves will be wired to the two relay boxes.
 
  #11  
Old 10-09-13, 04:40 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
After looking at the pics you have up now, (I still want to see inside the relay boxes and know their model #s) what I think you have is this:

Four zone valves somewhere, in two 'groups' of two.

One thermostat to each zone valve.

One group of two zone valves is wired to one of the relay boxes, and controls one of the pumps.

The other group of two ZVs is wired to the other relay box, and controls the other pump.

I do not believe that you will find any wiring from either of the relay boxes to any type of burner control.

Your burner is 'free running' at the HIGH setpoint of the aquastat.

There is 120VAC coming out of the red 'emergency switch' on the side of the boiler, going into the 4081 aquastat, and out of the aquastat directly to the burner.

As long as that red switch is ON, the burner will maintain the temperature setting on the HIGH side of the aquastat regardless of whether or not there is a heat call from a zone.

When there is a heat call, the corresponding zone valve will open, which will in turn operate the relay for the appropriate pump, and will circulate the already heated water through the zone (or zones if more than one is calling).

I can not see any value to this control scheme.

Please also take a picture (that we can read) of the data plate on the boiler.
 
  #12  
Old 10-09-13, 05:43 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Thank you so much for all of the information. I'm scratching my head trying to figure out why this is set up this way. In any case, here are the photos requested:

The two Honeywell Boxes:
Name:  Honeywell.jpg
Views: 1664
Size:  35.4 KB

The Data Plate:
Name:  Plate.jpg
Views: 4258
Size:  37.3 KB

Two different angles of the boiler/zone valves:
Name:  DifferentAngle.jpg
Views: 1956
Size:  40.9 KB:
Name:  ZoneValves.jpg
Views: 1307
Size:  40.0 KB
 
  #13  
Old 10-09-13, 05:46 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Well... I can't read the data plate or tell what model the relay boxes are...

So you will need to tell us...

and look the wiring over to see if it matches what I've described.
 
  #14  
Old 10-09-13, 05:55 PM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Sorry about that. Here is the plate cropped out.

Name:  Plate.jpg
Views: 5227
Size:  33.2 KB

When I go back downstairs I'll take more photos of the boxes.
 
  #15  
Old 10-10-13, 06:19 AM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
Alright, I have a little more info. It looks like the zone valves are run into the red emergency switch box, and then the emergency box is wired to the relays and the aquastat.

Attachment 19031
Attachment 19032

Maybe I'll take the cover off of the emergency switch tonight and see if the zone valves just pass through to the relays.

Just for good measure, here is a close up of one of the relays:

Name:  20131009_203606.jpg
Views: 1270
Size:  42.4 KB
 
Attached Images   
  #16  
Old 10-10-13, 07:22 AM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 17,962
Received 37 Votes on 32 Posts
I believe you need to wire the relays to the aqua stat.

Wait for troop but here is a diagram... The aquastat is a L6081A I believe....


Name:  aquastat.jpg
Views: 6349
Size:  32.3 KB
 
  #17  
Old 10-10-13, 07:26 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Aquastat is a 4081 ...

Relays are RA89 and there is not an 'extra' pole on those relays to wire to the aquastat.

To make this into a 'cold start', another relay will be needed.'

What is the make model of the zone valves?
 
  #18  
Old 10-10-13, 07:31 AM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
You guys are incredible. I'll get the make/model of the zone valves tonight.
 
  #19  
Old 10-10-13, 03:22 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Vix, in this picture, there is yet some other control previously unseen to the left of the upper transformer... what is that?

 
  #20  
Old 10-11-13, 07:52 AM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
I'll have to take a look tonight. Again guys, thanks for all of the help.

Here is a pic of one of the zone valves. They all appear to be the same.

Name:  20131010_183243.jpg
Views: 1215
Size:  44.1 KB
 
  #21  
Old 10-11-13, 11:50 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
That zone valve appears to be a " V8043F " ...

Let me know what that other control is that I mentioned...
 
  #22  
Old 10-14-13, 04:51 AM
Member
Thread Starter
Join Date: Oct 2013
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
NJTrooper - Here are some pics of the other controller. It looks to be pretty similar to the others, but i does appear to connect directly to the emergency switch:

Close Up:

Name:  20131014_063120.jpg
Views: 1186
Size:  30.7 KB

Zoomed out:

Name:  20131014_063131.jpg
Views: 1152
Size:  29.6 KB
 
  #23  
Old 10-14-13, 06:48 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
OK, I have no idea why there are three 24V transformers on the system... I could understand TWO, but three? Wonder what that third one is powering? Wait... I think I know... it could be powering the vent damper on the flue pipe. No... on second thought, and closer look, I don't see any vent damper on the system...

ANYWAY... after all this, we are back to the aquastat.

At the bottom right the wire leaves and goes to the burner assembly, yes?

At the upper left, that wire is coming from the red switch box, yes?

I believe that you will find that the wires into the upper left of the aquastat are 120VAC Hot, Neutral, Ground, (and it also appears there may be an unused RED wire with a cap on it). I strongly suspect that 120VAC supply is ON as long as the switch is ON, and this would account for the behavior you are seeing.

The only way to change this behavior is by some rather extensive rewiring... and/or the substitution of the two relays with DOUBLE POLE models that would allow controlling the circulators AND the burner.

Something about this wiring that I do NOT like, and an Electrical Inspector most likely would not like either:

In that red switch box, there are MIXED voltages... you have 120VAC LINE voltage, AND 24VAC LOW voltage wiring. I don't think this is up to code in ANY area. I know that in my area, it is not. One should not mix AC LINE and LOW voltage wiring inside the same box.
 

Last edited by NJT; 10-14-13 at 10:11 AM.
  #24  
Old 10-14-13, 04:29 PM
Member
Join Date: Oct 2013
Location: United States
Posts: 2,758
Received 21 Votes on 20 Posts
Trooper, how about this. Looking at the pics and the three trans. I believe the transformers control the zone valves. Why he's got three I don't know. Then he's got the RA89 relays to control the pumps. It looks like what he did was put in whatever was free. The aquastat looks like a simple high low with no cold start or zone control functionality. Simply put it looks as though the aquastat just runs the boiler on temp. decrease much like you would for a tankless setup. I think that when the t-stat calls for heat the pump comes on which lowers the boiler temp. and the aqustat kicks in to heat the water. The t-stats and the boiler are working independent of each other. If that aquastat wasn't working I bet the pumps would still work but the boiler wouldn't come on. The aquastat has no burner or pump terminals and the 89A's don't have terminals 5&6 which would give him some zone control also. Basically he's running this boiler as if he's getting his domestic hot water from it. With a cold start control and RA845 relays I think he would eliminate half his wiring and have it run properly. What do you think.
 
  #25  
Old 10-14-13, 05:10 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
It looks like what he did was put in whatever was free.
HA! I think that's true... probably whatever he could scam off a job.

I think we're on the same page with how it's wired.

Each pair of zone valves has it's own transformer, that's good, won't overload the transformers.

The endswitch of one pair of zone valves fires one relay, the other pair of zone valves fires the other relay, and runs the respective pump.

Yes, the boiler is 'free running', and WARM START... temperature being maintained by the HIGH setting of the 4081 aquastat.

I'm sure the Peerless didn't come with a Riello burner! I wonder where the burner cover is? Probably didn't fall off the truck with the burner. Or maybe was too big to fit in his lunch pail.

"I got it one piece at a time... and it didn't cost me a dime..."

I have no idea what that third transformer is for. The only way to know is to be there and trace the wiring. Maybe there's an LWCO that we can't see in the pics?

If this were mine, what would I consider doing?

The simplest thing to do would probably be to lose both of the RA89s and replace with something like a Taco SR-503 panel.

Wire the pumps and zone valves to the panel.

This would provide an ENDSWITCH which could be used to enable or disable the burner so it didn't keep the boiler hot all the time.

To go a bit further, I might consider a modern aquastat as a replacement for the 4081...
 
  #26  
Old 10-14-13, 07:17 PM
Member
Join Date: Oct 2013
Location: United States
Posts: 2,758
Received 21 Votes on 20 Posts
I cannot see what he's has for a burner control. For his eyes it's the control with the reset button an 4 terminals marked TT & FF. He could wire that into his aquastat and remove the 89's for RA845's or equivalent that has 6 terminals instead of 4 and you wire 5 & 6 into TT on the burner control. That way it will only run on a call for heat. The 89 relay is made if you want to maintain boiler temp. It's not made to do what he wants. To bad a couple of 845's didn't fall off the truck. If he is interested I would need the burner control number, maybe an R8184G.
 
  #27  
Old 10-14-13, 07:46 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Riello burner... it's got all that weird proprietary Riello stuff on it, not the common Honeywell primary controls.

Sure he could swap the 89s for a double pole job... but I think the SR-503 is the cleanest way. 120 V to the control panel, hook the zone valve wires to the TT inputs, the circs to the pump outputs, and then a simple wiring job to put the 120 to the burner in series with the endswitch in the 503.
 
  #28  
Old 10-14-13, 08:06 PM
Member
Join Date: Oct 2013
Location: United States
Posts: 2,758
Received 21 Votes on 20 Posts
I agree. Just thought about another option if he didn't want to go through all that wiring. It would be a lot better job though.
 
  #29  
Old 10-14-13, 08:51 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 17,962
Received 37 Votes on 32 Posts
IDK.... Dont those relays have XX?? It seems easy from my thinking...


Name:  stat111.jpg
Views: 1353
Size:  32.8 KB
 
  #30  
Old 10-14-13, 08:58 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 17,962
Received 37 Votes on 32 Posts
Never mind....,,,,,,,,,,,,,..


Name:  12343.jpg
Views: 1221
Size:  39.9 KB
 
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: