Help with Boiler issues. Continuous full cycles.

stumblinhorse

I moved into a house that has a Weil McLain CG Boiler and Amtrol 41 Gallon Boiler mate. It also has a Central Boiler E Classic OWB. E Classic is off. All Heat in the house is definitely off. Only need for boiler is hot water. When I moved in boiler was not working because of a fried rollout switch, so there was no hot water, noticed previous owner had amtrol dial set to maximum. Bypassed the switch for a couple days, till I got a new switch in, hoped my troubles were over. I moved the dial to 120* indicator. Hot water was very smelly, house was a little neglected from the previous owners. So couple of weeks ago I drained and flushed the amtrol. Hot water not smelly any more. But seems as though the boiler does a full cycle continuously. Boiler aquastat seems to doing its job. It is set to 170, boiler starts at about 130 or so and goes to 170 then shuts off. Then cools to 130 or so and turns back on. Not matter what I set the amtrol dial to the water is as hot as the boiler. PO left a new replacement 90-340 relay that I put in and no change.

Ideas? Is there a way to isolate the boiler from the amtrol? Trying to determine where the problem is. I ordered another 90-340 relay incase the one left in the house was also bad. Comes in on monday. If I could just simply disconnect the amtrol from the boiler and see if the boiler still is running I know it is the boiler. If it settles down, then I know it is the amtrol.

The Amtrol gets hot to the touch with having 150* water in it. So I probably need a new one anyway, Local quote for install of a HTP SS Ultra is $3700. I can't afford that right now so trying to troubleshoot my problems.

Thanks for any help you can give!

rick in Alaska

Does the Amtrol have a digital thermostat on it? They have a nasty habit of failing, which might be your issue. Depending on how it is wired, you might be able to just take the signal wire off and see if the boiler stops. If it is digital, does it have a light on saying it is on? Pictures would help to see if there might just be a stuck zone valve, if it has one.
Rick

JUGHNE

Is the pump to the indirect tank working?
Sounds like this is all a control problem, If the tank does not leak it is probably fine. IMO

HVACNUT

Agree with @rick in Alaska about the Amtrol thermostat. Or a short between the Amtrol stat and relay. Is the Thermostat/Circulator light lit on the control module with the water heater thermostat turned down all the way?

stumblinhorse

Not the digital Amtrol. Simple rheostat version.

stumblinhorse

JUGHNE said:

Is the pump to the indirect tank working?
Sounds like this is all a control problem, If the tank does not leak it is probably fine. IMO

There is an ever so small leak at the bottom of the tank if I shine up at it. Not even enough to drip.

hot_rod

Maybe the Central OWB is acting like a cooling tower😲 Check the piping, are the pipes to the Central or it’s HX warm?

stumblinhorse

hot_rod said:

Maybe the Central OWB is acting like a cooling tower😲 Check the piping, are the pipes to the Central or it’s HX warm?

Definitely yes. The pipes to the Central Boiler HX are warm. How would that tell the boiler to stay worm?

rick in Alaska

Although that control is pretty reliable, it can fail. Try taking the wire loose and see if that helps.
Rick

stumblinhorse

Which wire should I remove? And from where? From the the Amtrol? Or into the control valve or on the way out of the control valves. White comes out into yellow into valve. Red comes out of amtrol joins with all the other T-stats reds of the house and one other red (maybe to boiler?) Then 2 reds out of the control valve and a yellow.

Sorry for the newb questions.

rick in Alaska

Can't see how the wires go, or to where, but the best way to eliminate the Amtrol thermostat being the problem would to just take the wire off the Amtrol. If the problem persists, then it is not the thermostat. Is the Amtrol hooked up as a zone with a zone valve? If so, maybe the zone valve is stuck open. Pictures would help for sure.
Rick

hot_rod

It sounds like a continuous call for heat on the boiler. Locate the TT connections and remove the wires, do you hear a relay click, open?

If so, somewhere a valve, thermostat or shorted wire is telling the boiler to run. With or without a hot water call.

The piping often get confused and the two may be in series. So every time the Weil runs some teat goes to the central and is dumped up the chimney.

A drawing of the piping, with flow arrows might help determine that.

stumblinhorse

rick in Alaska said:

Can't see how the wires go, or to where, but the best way to eliminate the Amtrol thermostat being the problem would to just take the wire off the Amtrol. If the problem persists, then it is not the thermostat. Is the Amtrol hooked up as a zone with a zone valve? If so, maybe the zone valve is stuck open. Pictures would help for sure.
Rick

Couple of pictures.

stumblinhorse

House is 5 zones: Basement, Main Floor, Master Bed/Bath, Garage and Hot water. Yes there is a control for hot water.

rick in Alaska

Check out the zone valve for the Amtrol. See if the lever, right under the wires, moves easily from left to right with the Amtrol not calling for heat. If it does, take off one of its yellow wires and then see what the lever does. With the yellow wire off, the lever should only move easily for just part of the way. If it still moves easily with the wire off, then the zone valve is stuck open and needs to be repaired.
If when you take the yellow wire off and the zone valve closes down, then it is getting a signal to be open and the wire to the Amtrol needs to be traced down and checked.
Rick

hot_rod

DSo those green lines get warm when the boiler runs? Is the piping behind the Central warm in the summer? Is the Central located above the Weil? if so, you may be thermosiphoning some of your energy dollars to the OWF.

There could still be a wiring glitch keeping a heat call present. A VOM would be the easiest way to track it down.

stumblinhorse

rick in Alaska said:

Check out the zone valve for the Amtrol. See if the lever, right under the wires, moves easily from left to right with the Amtrol not calling for heat. If it does, take off one of its yellow wires and then see what the lever does. With the yellow wire off, the lever should only move easily for just part of the way. If it still moves easily with the wire off, then the zone valve is stuck open and needs to be repaired.
If when you take the yellow wire off and the zone valve closes down, then it is getting a signal to be open and the wire to the Amtrol needs to be traced down and checked.
Rick

With boiler power switched off, Lever moves a little bit. With power on it moves easy all the way to the right. Not sure if the amtrol is calling for hot water.

What I have been doing for the last couple days since I noticed this, I only run the boiler for a few hours a day to have hot water. I just turn the switch off for the daytime, after showers etc.

stumblinhorse

hot_rod said:

DSo those green lines get warm when the boiler runs? Is the piping behind the Central warm in the summer? Is the Central located above the Weil? if so, you may be thermosiphoning some of your energy dollars to the OWF.

There could still be a wiring glitch keeping a heat call present. A VOM would be the easiest way to track it down.

Green lines get hot definitely. Haven't checked the piping to outside at the OWB when the boiler is on. I turned the boiler on right now and will be hot in a little while. OWB is downhill from the Weil.

stumblinhorse

BTW thank you guys so much for helping me!

rick in Alaska

If that lever moves when it is powered up, it is looking for hot water. If the tank is hot, that lever should not move very much. So, unless the tank was needing to be heated when you powered it up, the zone valve is getting a signal to open up and heat the tank. That would most likely indicate a bad thermostat on the Amtrol .
Rick

stumblinhorse

rick in Alaska said:

If that lever moves when it is powered up, it is looking for hot water. If the tank is hot, that lever should not move very much. So, unless the tank was needing to be heated when you powered it up, the zone valve is getting a signal to open up and heat the tank. That would most likely indicate a bad thermostat on the Amtrol .
Rick

Ah Perfect! I will let it run for a few hours and see if it ever gets tough to move. I will report back.

stumblinhorse

rick in Alaska said:

If that lever moves when it is powered up, it is looking for hot water. If the tank is hot, that lever should not move very much. So, unless the tank was needing to be heated when you powered it up, the zone valve is getting a signal to open up and heat the tank. That would most likely indicate a bad thermostat on the Amtrol .
Rick

When the hot water is up to temp the valve moves only a small amount. This proves it is the boiler.

That is interesting, since the water gets to boiler temp no matter what it is set to.

Any ideas where to look on the boiler?

stumblinhorse

For my education, since the control valve is pretty much closed when the hot water is up to temp, why does the hot water get so hot? Boiler Hot water still sneaking by?

HVACNUT

Does the circulator run while the zone valve is closed? It shouldn't. With the zone valve supposedly closed, the tank thermostat and wiring for it seems ok. It might be just bypassing the zone valve.

rick in Alaska

The zone valve has a ball inside that might have come apart. You would have to take it apart to see, which would involve taking the pressure off the zone valve and disassembling it. You can get a rebuild ball for that valve and just install it.
Rick

hot_rod

Really the circulator should not run if there is no heat or HW call. Does it? A bad ZV could be leaking, but not if the circ is stopped.

Also the boiler should only fire when a heat of DHW call, it should not be hot always?

Sometimes when they tie OWB into a circuit like that the wire the circuit to run to move heat from the OWB to the system, via an additional control.

I don't suppose a wiring diagram was left with the system. If not you need to trace everything and try and determine their control logic.

stumblinhorse

hot_rod said:

Really the circulator should not run if there is no heat or HW call. Does it? A bad ZV could be leaking, but not if the circ is stopped.

Also the boiler should only fire when a heat of DHW call, it should not be hot always?

Sometimes when they tie OWB into a circuit like that the wire the circuit to run to move heat from the OWB to the system, via an additional control.

I don't suppose a wiring diagram was left with the system. If not you need to trace everything and try and determine their control logic.

Well I will have to start a diagram. To compound the confusion there is another Taco in the basement for that zone. It is confusing. Good thing the person that sold and installed the OWB lives across the street...

hot_rod

Probably save a lot of guess work by chatting with the person, across the street, that installed it