I’m about 2 weeks away from closing on a house, and I discovered yesterday that I’m an idiot when it comes to working the furnace. Some backstory:
I had the home inspected last Wednesday, but I wasn’t able to be there when he did it as I was out of town for work. My realtor attended the inspection for me instead, so I didn’t get to ask the questions I wanted to. When the inspector was there, he turned the thermostat up to check if the furnace came on and apparently forgot to turn it back down. Hence, the next time I came to the house (Thursday evening), it was over 90 degrees in there. I turned the thermostat back down to a reasonable temperature (62, since the house is empty, the heat is just on to keep the house from getting musty at the moment) and left.
When I went to the house this weekend to do some work, it was about 55 degrees in there and the furnace wasn’t running. I turned the thermostat up and the furnace didn’t come on. Bleah.
My brother and I fiddled around a bit and discovered that if you open the valve on the side of the furnace to let some water out (there’s a bucket underneath the valve, apparently just for this purpose), then the furnace kicks on. It doesn’t stay on, though. We were there for a few hours, and although I had put the thermostat up to about 68 degrees, the furnace shut back down by the time the house warmed up to about 58. I went down and let a little more water out of that valve, and the furnace kicked on again. I don’t know if it stayed on, since I had to leave.
The furnace is gas, and the distribution system is steam through radiators. Can someone tell me what I’m doing wrong? Why won’t the furnace stay on until the heat is up to where I set the thermostat? What’s going on with that valve where I’m letting water out, and why does the furnace come on when I fiddle with it? Am I screwing something up by doing that?
Sorry this is so long…TIA to anyone who’s willing to help me. I looked on Ask Jeeves, but they only referred me to places I could find people to come and service my furnace, I couldn’t find anywhere that it explained how it all worked.
A gas furnace is not something that amatuers like you and I should being monkeying around with on our own. The water probably is not from your furnace, since gas furnaces do not use or collect water. It is probably from your pipes and radiators. The valve probably is bad (not letting excess water out) and the furnace is turning off as a safety factor to keep something from blowing up.
Everything I said after the remark about amateurs is purely guess work. I suggest you call in an expert.
I’d say listen to kniz. I’ve seen the end product of a house destroyed by a gas explosion in a nearby neighborhood when I was growing up. I’ve seen pictures of buildings hit by US 2,000 pound bombs that had more structure left standing (seriously).
I’m not saying you will necessarily blow yourself up but given the disaster potential I’d have an expert look in to it and try to fob the costs off on the seller (or at least split them).
No offense, but you guys have to be kidding me. There are millions of homes across the country with this type of heating system, and I don’t think it takes a professional to manage the basic operation of the thing. The furnace and general heating system was inspected less than a week ago and found to be in perfect working order. It’s just me that doesn’t understand how to make it function the way it’s supposed to…I was hoping someone here could explain it to me. That’s all.
Fine, if you are willing to depend on the assumption that there aren’t inspectors that overlook things and are willing to assume that nothing went wrong with the system due to it being left on 90 degrees for a long period. Actually, I should have said “if you want to depend on an inspector that screwed up once by leaving the heat set too high.”
Go ahead and DIY, but don’t sue me for not advising you to consult an expert. Whack-a-Mole gave you good advice about getting the seller to pay for it. Why not call the inspector.
From the experience of someone who has a single line steam heating system.
Steam heat is great and there are plenty of maintenence steps that you can perform on your own once you get to know your system.
First off, you have a boiler, not a furnace. The valve you are opening allows you to clean out the dirty water that collects at the boiler level. During the heating system you generally need to drain a quart or two of water out of the system on a weekly basis to keep sludge from building up. You need to make sure your boiler has an autotmatic feed that adds water back to the system when the water level gets low. If it is a newer system, it will be automatic feed.
From what you described, my best guess is that when the system ran at a high level for a week, with no cleaning (especially if it sat idle over the summer), some sludge and rust was set free and collected either in the boiler or at one of the valves close to the boiler. When the burners kick on the water is heated and steam created. There is a pressure override that will turn the burner off if too much pressure builds up in the system. The pressure may be building up due to a clogged pipe or valve.
When you drain some water out, you are also releasing some pressure and adding cool water to the mix. So it will turn back on for awhile.
You do need to call a pro for this one. They will most likely flush the system out and hopefully give you tips on how to get the most out of the system. When looking for a vendor, make sure that they have experience with steam systems. Many heating/plumbing contractors don’t perform much work with steam.
Thank you Squink and barker…this is the sort of info I was hoping for.
barker…a few more details that may or may not be helpful:
[ul]
[li]The system ran on high for just a little longer than a day, not a full week. The inspection was on Wednesday morning, I came to the house and noticed the heat on Thursday afternoon.[/li][li]The bucket under the valve had been empty prior to the inspection last Wednesday. When I got to the house Thursday, the bucket was full of sludgy water. I emptied it, and then ran a little more water into the bucket on the two occasions I mentioned in my OP. This subsequent water was also fairly sludgy looking.[/li][li]The system is old…probably 25 years or more. Does this make it unlikely that it has an auto-feed when water is let out of the system? How would I know if the system is short on water, and how do I add more if need be?[/li][li]I’ve seen some references in the links that Squink provided regarding the glass tube that shows the water level. I’d heard somewhere that the water level should be about halfway up the glass tube. The water level in the glass tube on my system is very low, probably only an inch up from the bottom (less than 1/4 of the way up the tube). Could this be part of the problem?[/li][/ul]
I have a call in to the inspector who turned the furnace on in the first place, and hopefully he’ll have some information for me, or at least can refer me to someone who can assess the system and tell me if anything needs to be done to it.
A day could still do it if there was enough crud in the system. Again this my best quess from personal experience.
The system should not leak on its own. It may not be sealing properly due to something being stuck in the valve or a bad ring or washer. We have always ran the water out until it was clear.
For the auto water feed, if you drain water out, you should here water going back in. Kind of like the sound when you turn on any fawcet. If not auto feed, it would depend on your system. (That is one reason you should have someone knowledgable of steam systems go over the system with you.)
Our’s is maintained at 1/3 to 1/2 up the tube. And the water should be fairly clear. Any other information would depend on your system.
perhaps the reason the boiler fired up when you drained it is because there was an auto feed, which dumped in new cold water. Just a guess.
if you don’t have an auto feed, look for a valve on a pipe going into the top of the boiler. That’s the … you guessed it - Manual Feed!
open the manual feed & let it run till the sight glass is 1/2 - 2/3 full.
One other important component of a steam boiler which you should acquaint yourself with is the Low Water Cutoff (LWC). This is a device which shuts down the boiler is the water level is too low. It may need draining as well. It also has a spout where sludge can be drained out. Have the inspector give you a LWC primer. It should be tested periodically as well, to be sure that it really does shut down the boiler if it runs dry.
this stuff is not rocket science, you can maintain it yourself. Be sensible, and you have nothing to fear - there’s nothing inherently dangerous about this being a gas fired boiler (as opposed to oil). You’re not mucking around with the gas, just the water it boils.
and one more thing. IMHO, It’s unfortunate that you couldn’t attend the inspection. I’ve learned a TON from following a house inspector around & asking questions. Depending on your relationship with the realtor [sub]some are slime[/sub], you may or may not want to trust them to represent your best interests at the inspection. Personally, I would never buy a house until I was able to schedule an inspection that I could attend. When it comes to finding faults in a house, your interests (full disclosure) may be far from the realtor’s interests (make the sale). As a matter of fact, I recently learned a lesson the hard way, to not even use a home inspector recommended by a realtor. Again, too much conflict of interest.
audient…thanks for that info! Now that you mention it, my brother did point out a valve on the other side of the furnace which produced a water running sound when you opened it. We weren’t sure exactly what it did, so we closed it back up right away. I’m guessing that my furnace doesn’t have an auto-feed.
I’m hoping that my inspector might be able to give me a quick rundown of what else I need to know about the boiler when he calls. I have a few questions for him based on the comprehensive report he sent. As far as not being able to attend the inspection…well, it couldn’t be helped. I do trust my realtor, and since the sale is already made (I’m about 2 weeks from closing) and I can’t cancel my contract unless they find major structural defects or termite damage, she has no reason to withold info…she couldn’t anyway, since I got a full report directly from the inspector. I picked the inspector on my own, based on recommendations of a few people I work with who had all used him. The inspector’s report seemed very thorough and certainly didn’t pull any punches where potential problems were concerned.
Thanks again…hearing from people who actually have one these systems has been helpful.
on 2nd thought, i’m full of hooey. there’s no thermostat in the boiler, the thermostat is on your wall. The boiler doesn’t fire up & down based on the temp of the water in the tank.
