My 35 year old Homart Gas fired Steam Boiler from time to time won't kick in. When it works, it's fine for a few days to weeks, but sometimes when the weather gets real cold, it will come up in the morning, but then stop running and not make it to the temperature set on the Thermostat. I've even just recently replaced the Thermostat to a new Honeywell digital one, thinking that it was the problem. To give you a little history as an aside, I've been working with a manual water feed system for the past 20 years or so, being that the old Auto Feeder would get stuck in the "open" position and allow too much water to come into the boiler thereby creating a high cutoff condition. Manually feeding water has been fine with me every few days to about a week during the winter time. So that's not the issue. But recently I've found that the system would not heat up to its target temperature, and it would just stop! We happen to schedule the boiler to go down to 55 degrees over night so we can sleep, and then I have it come up to 66 starting at 5:15am. This morning it tried to make it to 66, but stopped at 60 degrees. I went down to the basement and turned the boiler switch off and on a few times, but no dice. I then went up to raise the thermostat temperature up to about 73, and then I went back down to the boiler and turned the switch off and on several times and also hit what I think is the white Actuator device (or maybe modulator device, not sure), and the boiler then came on. I then went back upstairs to the thermostat and brought it back down to 66 degrees. I checked to make sure that the boiler was still running, and it was. I then went to work and called my wife to see if it ever made it up to the target 66 degrees, but she said that it was still at 60, and it seemed as though the boiler turned off again. Could it be that it might be one of these electrical devices that's at fault (either the Switch or the Actuator Modulator device)? Any help here would be greatly appreciated! Thank you very much!

 

I doubt that the problem is with your room thermostat but is instead a problem with one of the boiler-mounted controls. I would need a whole lot more information on the entire system to offer any suggestions.

When (if ever) did you last have a heating professional look at this system?

 

The last person who we hired to check it out was about 20 years ago. I've actually kept it maintained myself, although I'm a bit of a novice at it. But to my credit, I've worked on the boiler over time. By trade, I'm a computer network administrator with an electronics background, so I'm fairly good with my hands. In the past, I've drained out the boiler periodically (about once a month), via the blow down valve. (Nothing comes out of the lower drain valve. But that seems to be okay.) I've also replaced the blow down valve, due to the old one getting stuck in the closed position at one time. In addition I replaced the 10" long glass gauge and rubber grommet washers that hold it in place. (This once leaked water, and needed replacement.) I applied pipe cement compound to leaky valve stem nuts on several of my radiators throughout my house, which seemed to have sealed them nicely. I have a one family two level small house along with a basement that is where the boiler room resides.

But I should say that at this time, things seem to be working normal again. I think it's because I did try one other thing. The last thing I did, after my first email posting, was to replace the boiler on/off switch itself. It's just a simple single pole heavy duty switch, but I believe it may have been the source of my problem. I disconnected the old one, and I hooked up an Ohmmeter to its contacts to test it. I used a Fluke DVM, and I set the scale down to 2Kohms. When I toggled the switch back and forth, I noticed that the resistance only went down to about 15 ohms from time to time. If I rotated the switch while in my hand, it looked like the reading would fluctuate, as I made sure that meter leads stayed firmly on the contacts. I figured over the 35 years that I've had this boiler, it's possible that the switch could be worn out a bit. So I replaced it with a new one a couple of days ago. So far, so good.

However I should say though that in the past, things have looked bright for a while as in this case, but then after some time, usually after I've manually fed a substantial amount of water into the system, I'll then notice that the boiler will start failing again. I don't know if it's because it has a new water level to contend with, or if I'm hovering around the high level cutoff point, or what? But I'm hoping things are okay at this point. I guess it may still be a work in progress at this stage, until I know for sure that things are completely fixed. I hope I've been able to give you the information that you need. I really do appreciate your input and all of your help!

Thank you very much,
maypodude

 

Well, after giving it some time to work with the new Boiler On/Off Switch in place, it looks like we have a winner! My boiler's been fine for the past couple of weeks reaching the target temperature each time, even after several manual water feedings. Had I known for sure that the problem was coming from this simple electrical part, I might not have sprung for the cost of a new thermostat. But you live and learn. I actually like the new Honeywell digital thermostat, because it allows me to schedule precisely what temperature I want in the house at what times. The only weird thing is that although this is a highly precise device, being that it makes the boiler closely stick to the set temperature, I find that now my boiler runs more often then it use to with the old thermostat. I also find that I'm manually feeding water into the boiler more often than before. I'll bet I'm probably going to have a higher gas utility bill as a result. My old thermostat use to kick in when the room temperature went a couple of degrees lower than the set temperature, and it use to turn off a couple of degrees higher than the set temperature, thereby making the stretches of time that the boiler was off longer. Of course it would make the climate a bit unbearable from time to time, both high and low, due to the wider swings. But it was something we lived with. I guess there's some value in the old devices in that sense. However I do need to work on programming the new thermostat a little more. I'm sure I'll be able to realize the efficiency aspect a lot better, once I schedule it to lower the temperature when no one's home during certain days as I've already done with the overnight setting. That part may still be a work in progress. But other than that, my system looks good at this stage!

Thanks again!
Maypodude