Cycling issue

fxrgrunt

Good morning all,

Been having an odd issue lately that has not happened previously. Once the boiler starts up after about a minute or two it shuts down then kicks back on a runs as normal. It's a PSB5 boiler and has a cycle guard 400. I'm wondering if the cycel guard is having an issue causing this but the test light isn't on when it does it. Any help or direction would be appreciated. Thank you.

Damian

EdTheHeaterMan

See EDIT:

I assume you are referring to a PSB series boiler manufactured by Dunkirk



The cycle guard may be the issue, but there may be other issues. The flame sensor may be dirty, there may be a thermostat problem, Older thermostats have heat anticipators, newer thermostats have batteries. the pressure gauge pigtail may have some sediment that is causing issues. The end switch on the auto vent damper may also be the culprit. That is just a few of the items that I would have inspected, cleaned, adjusted, or otherwise serviced on an annual maintenance visit before the heating season started.

How old is your boiler? When was the last professional service completed ?

Edit:
After looking at your other posts, I see you have the Bryant or Carrier boiler. That boiler is made for them by Dunkirk.
on page 22 of the I/O manual you will find this maintenance info:
https://dunkirk.com/sites/default/files/PSB Series II IOM Rev. C.pdf

I recommend a Professional do this, however you seem to be on top of things and may be able to complete many (not all) of the tasks.

The part about the ignition system maintenance is not included in the manual, you would need to look in the information on the ignition module that should also accompany the manual with the boiler. Nor sure what control you have, however, here is one that is similar to the one you have. https://documents.alpinehomeair.com/product/S8610U3009 Installation Instructions.pdf
In reference to the short cycling issue, this info is in the aforementioned document


Regarding the part about Main Burner lights? YES ....... System runs until call for hear ends? NO
That box has some information that a professional should be well qualified to determine if that is the reason for the short cycle you mentioned.

EBEBRATT-Ed

I agree have it serviced. The pigtail and flame sensor and low water cutoff are the likely problems as @EdTheHeaterMan mentioned

ethicalpaul

Up to 82.7% efficient! For when 82.6% just isn't good enough!!

fxrgrunt

EdTheHeaterMan said:

See EDIT: I assume you are referring to a PSB series boiler manufactured by Dunkirk The cycle guard may be the issue, but there may be other issues. The flame sensor may be dirty, there may be a thermostat problem, Older thermostats have heat anticipators, newer thermostats have batteries. the pressure gauge pigtail may have some sediment that is causing issues. The end switch on the auto vent damper may also be the culprit. That is just a few of the items that I would have inspected, cleaned, adjusted, or otherwise serviced on an annual maintenance visit before the heating season started. How old is your boiler? When was the last professional service completed ? Edit: After looking at your other posts, I see you have the Bryant or Carrier boiler. That boiler is made for them by Dunkirk. on page 22 of the I/O manual you will find this maintenance info: https://dunkirk.com/sites/default/files/PSB Series II IOM Rev. C.pdf I recommend a Professional do this, however you seem to be on top of things and may be able to complete many (not all) of the tasks. The part about the ignition system maintenance is not included in the manual, you would need to look in the information on the ignition module that should also accompany the manual with the boiler. Nor sure what control you have, however, here is one that is similar to the one you have. https://documents.alpinehomeair.com/product/S8610U3009 Installation Instructions.pdf In reference to the short cycling issue, this info is in the aforementioned document Regarding the part about Main Burner lights? YES ....... System runs until call for hear ends? NO That box has some information that a professional should be well qualified to determine if that is the reason for the short cycle you mentioned.

First, thanks for all the great info. It is a 2014 boiler. I have done much of the work myself since moving in here in 2018. I have had a service every year though for insurance purposes. The last one was in October. That was also the first service that any of them messed with the ignition system and cleaned the burners. Wondering if that threw something off. I cleaned pigtail in October as well and installed low pressure gauge off T so while that could be an issue I don't think it would have clogged that quickly. I did just replace the batteries in the Honeywell thermostat. I didn't mess with anything with the damper ever or cycelguard wiring. I just assumed it may have something to do with that. I will try to troubleshoot using your guidance from the manual. 

fxrgrunt

So further question. As I was checking on some of these things a call for heat came and it was for about 8 mins or so when the intermittent test came on. Does the cycleguard 2090 start 20 minutes from the call for heat no matter what or does it pick up where it left off when it last shutoff (example: if it was running for 12 minutes when it reached thermostat temp and shut down would it only run 8 mons when it came back on) 

ethicalpaul

It depends how it's wired. From Peerless, it is wired so that it is always powered up even with no call for heat...so it's cycling its test 24/7. I'm not sure about your boiler.

The manual can show you more details ( https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Hydrolevel-45-410-2090-Install-Instructions.pdf ), including another optional feature that you might have wired up called "SmartCycle" which is that it will reset its timer on a call for heat so that the call for heat can run for 20 minutes (for your model 2090) before doing its test.

But you said the green light isn't on when your boiler shuts down, right? So that tells us the cyclegard isn't causing it (assuming correct wiring and operational 2090)

fxrgrunt

ethicalpaul said:

It depends how it's wired. From Peerless, it is wired so that it is always powered up even with no call for heat...so it's cycling its test 24/7. I'm not sure about your boiler. The manual can show you more details ( https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Hydrolevel-45-410-2090-Install-Instructions.pdf ), including another optional feature that you might have wired up called "SmartCycle" which is that it will reset its timer on a call for heat so that the call for heat can run for 20 minutes (for your model 2090) before doing its test. But you said the green light isn't on when your boiler shuts down, right? So that tells us the cyclegard isn't causing it (assuming correct wiring and operational 2090)

So after sitting in the basement for awhile to wait it looks like it's the intermittent testing shutting it off. It's happening around 6 min 30 seconds after each heating call. I had gotten mixed up with the light being off because I had a previous issue where the pressure was hitting 2 plus lbs and it shut down off the pressuretrol with no light. That issue was solved. I had two of my gorton 2s on an antler not tilted enough to allow the condensate to drain. Ones I fixed that pressure was good to go.

Anyways. So the question is, does it make sense to wire it for smart cycle so it gets that full 20 minute cycle every time it kicks on? Pictures below of current wiring.

fxrgrunt

Just realized your probably would need to see wiring inside cyclegard huh?

ethicalpaul

Honestly I wouldn't bother with the SmartCycle. I am a tinkerer and I haven't even bothered with mine. The 90 seconds off time isn't hurting anything and it's going to happen eventually.

I can't think why it would come on consistently at about 6 minutes 30 seconds after the start of the call for heat...it should either be totally random or consistently 20 minutes after the start of the call for heat (for your model--mine for example is a 1560 so it comes on every 15 minutes for 60 seconds).

Hap_Hazzard

If you have an automatic vent damper, does it close and reopen when this shutdown occurs, or does the gas valve just shut down?

Re. the CycleGard, do you ever see the green light come on? Mine stopped working for a while, but when I put a meter on it to test it, it started working again. Also, I would bother with the SmartCycle feature.