Flaky Burnham Boiler

jfschachter

I bought a Burnham Boiler for a steam system in Brooklyn, NY in 2021. The heating system is flaky and really annoying. When temperature demand was constant at 68 degrees, it functioned fine. However, when I moved to a daily programmable Nest Thermostat, the heating became flaky. Sometimes it did what the thermostat asked. But from time to time, the temperature would not come on into a warm mode in the morning, e.g. go from 65 degrees to 72. I would wake up and find the furnace cold. On other times, it could not maintain 65 (one one occassion it went down to 55). Only power on/off on the furnace or touching the contacts. restarted it. The same flaky behavior occurred when using an Emerson thermostat, the only difference being the programming is M-F and Sa/Su only. This behavior continues to occur. Now I am being told that the thermostat is still the issue. They want me to try a third thermostat. That seems completely ridiculous. How many thermostats do I have to try before it's evident that the furnace has an issue? So... seeking advice on people who have seen Burnham boilers not acting properly in this manner. Is the ignition suspect? Is the wiring faulty? I know some other Burnhams were recalled. I want an HVAC opinion from someone who knows Burnham. I do not, I repeat, do not want to be told to change the thermostat.

Jamie Hall

What you are describing is almost certainly the thermostat.

However, since you don't want to be told that...

I can't help you, even though I have a pretty good idea what the problem is.

kcopp

Just as an experiment.... switch back and see if that helps.
Nothing ventured.. nothing gained.

jfschachter

if Burnham works only with certain thermostats, please let me know which those are. I would, however, mention that about ten years ago someone submitted another issue of Burnham with a thermostat. Like in my case, the therm asked for a higher temperature, but the boiler did not do it. The discussion centered on the boiler itself, and not at all on the thermostat. https://www.doityourself.com/forum/boilers-home-heating-steam-hot-water-systems/515297-burnham-boiler-thermostat-set-72-f-house-62-a.html

delcrossv

It's apparent in reading the post, that was a controls issue.

STEAM DOCTOR

Lots of the "smart" thermostats, take an unearthly amount of time to reboot, when there is an interruption of power. Let's say your Low water cutoff is first in the circuit and your thermostat is second. Just for example. No separate transformers or relays involved. Every time low water cutoff cuts out (either because of low water condition or because it's a cyclegard) the smart thermostat will loose power and need to reboot. Not an issue with an old fashioned, or battery powered thermostat. Not saying that's your situation. But certainly a possibility. I had a customer recently with a cyclegard cutting out every 20 minutes (I think) and thermostat would take approximately 10 minutes to reboot. Total heating cycle was reduced to 20 minutes or something like that.

Long Beach Ed

The boiler relay needs a clean analog switched thermostat. Most have a pair of contacts in them that switch on or off, like a light switch. Some electronic models have an electronic "switch," like an SCR - a silicone controlled rectifier - for "contactless" switching. This can be undependable in controlling an inductive load like the boiler's power relay.

So it's not your thermostat, but it may be your thermostat's internal switch design. You can rule this out by substituting a less complex thermostat with plain contact switching. If the problem goes away and you insist on Chinese electronics to switch your boiler, you may be able to circumvent the problem using an additional power relay that draws less current in series with the Burnham's power relay.

You should also investigate Steam Doctor's excellent recommendation above that touches on a similar possibility.

Jamie Hall

I think we lost him, folks. He explicitly said he didn't want to change the thermostat... which he needs to do... so I suspect he's gone away.

pedmec

Its not going to be the thermostat losing power. The low water cutoff on a Burnham does not interrupt power to the thermostat like some steamers. My guess is you're using the energy savings mode or your constant lowering of the temperature is messing with the learning feature. Just a guess. But if it worked with another digital, not a smart, thermostat then its not the boiler that is malfunctioning

EBEBRATT-Ed

He could be trying to run the Nest with out a C wire.

mattmia2

you don't need to change the thermostat, you need to power the thermostat. the tech should have known that.

dabrakeman

I have a smart thermostat that needs continuous power thus it has a 3 wire system with a common wire that was added after I got the thermostat. When it was originally put in I had issues because the way it was originally wired the power to the stat was really still in series with the ptrol and LWCO so if the LWCO for instance activated it cut the thermostat off from power causing the stat to have to reboot. The reboot would only occur after the LWCO allowed power to be restored to the boiler and this reboot usually ended with the stat causing control issues wildly off target. This issue was completely resolved by wiring a relay in that isolated the thermostat power supply from the control/safety devices. The devices of course still function and shut off the boiler when needed but the stat is allowed to continue to do what it was doing without loss of power. This of course would not be an issue with a simple battery powered thermostat.

mattmia2

dabrakeman said:

I have a smart thermostat that needs continuous power thus it has a 3 wire system with a common wire that was added after I got the thermostat. When it was originally put in I had issues because the way it was originally wired the power to the stat was really still in series with the ptrol and LWCO so if the LWCO for instance activated it cut the thermostat off from power causing the stat to have to reboot. The reboot would only occur after the LWCO allowed power to be restored to the boiler and this reboot usually ended with the stat causing control issues wildly off target. This issue was completely resolved by wiring a relay in that isolated the thermostat power supply from the control/safety devices. The devices of course still function and shut off the boiler when needed but the stat is allowed to continue to do what it was doing without loss of power. This of course would not be an issue with a simple battery powered thermostat.

or a mechanical t-stat. i'm not a fan of the batteries go dead while you're gone and the pipes freeze problem.

ChrisJ

mattmia2 said:

dabrakeman said:

I have a smart thermostat that needs continuous power thus it has a 3 wire system with a common wire that was added after I got the thermostat. When it was originally put in I had issues because the way it was originally wired the power to the stat was really still in series with the ptrol and LWCO so if the LWCO for instance activated it cut the thermostat off from power causing the stat to have to reboot. The reboot would only occur after the LWCO allowed power to be restored to the boiler and this reboot usually ended with the stat causing control issues wildly off target. This issue was completely resolved by wiring a relay in that isolated the thermostat power supply from the control/safety devices. The devices of course still function and shut off the boiler when needed but the stat is allowed to continue to do what it was doing without loss of power. This of course would not be an issue with a simple battery powered thermostat.

or a mechanical t-stat. i'm not a fan of the batteries go dead while you're gone and the pipes freeze problem.

That's not an issue if you run a C wire like any remotely modern thermostat should have.
It's also not an issue if you just change batteries once in a while. Similar to clocks and smoke detectors.