I'm new to this forum, and hoping to get some help with maintaining my residential steam heat system. I'm a novice at home repair, but I'm good at math and handy with tools, and enthusiastic about learning to care for the system myself. I'm also concerned there might be a serious problem that needs professional help.
I live in a 1920s duplex in the Boston area. It's a one-pipe steam system with a gas-fired Burnham boiler, which I had installed in 2009. It's been serviced about once a year by a general HVAC company. The pipes/radiators have had no maintenance in at least the past two decades. The radiators seem to be mostly the original ones except one small one in the third floor bathroom that looks newer. The house has hard water.
I'm recently divorced, and as I've taken over maintaining the house, I've discovered a serious problem with the heating system: the low-water cutoff on the boiler shuts down the heat every ten hours or so. I go down to the basement and refill the sight glass to about an inch from the top every morning, and it's shut off again by the time I get home in the evening. If I refill it then, it will be out again before morning. There's a sticker on the boiler that says it shouldn't need to be filled more than once a month. I believe that until 2015 it never needed to be done more than once or twice a year.
The glass is pretty full of rust and sediment, and there's a bucket below it that's always full of rusty water. I've observed steam rushing out of the openings around the sight glass, and drops of water leaking down the sides, but I'm not sure how it leaks enough to keep that bucket full.
Once I started paying attention, I became aware of some other issues. The third floor bedroom radiators all hiss and spray small amounts of steam, and overheat the rooms they're in. The second floor living areas are comfortable and quiet.
I talked to a local plumber who encouraged me to try replacing/repairing the valves on the radiators. I then read through The Lost Art of Steam Heat and We Got Steam Heat, and a number of threads in this forum. I felt confident enough to lower the Pressurtrol on the boiler from 5 to 2, and I boiled the radiator valves in vinegar, which did pull a lot of scale and dirt off, but doesn't seem to have helped with either the hissing/overheating or the low-water issue. I have some ideas about what to do next, but also some questions.
My best guesses about things I could reasonably do are:
- flush/clean the boiler by opening the lowest faucet on it when it is cool, letting all the water run out, refilling it, and repeating this until the water coming out runs clear.
- put some kind of descaling agent (citric acid? a commercial boiler cleaner? nothing?) in the boiler to clean out sediment and rust in the boiler and the pipes/radiators. Continue the flushing/cleaning process as above.
- replace the sight glass.
- replace the radiator valves. most of the valves are roundish and say 'Dole' on the bottom with some numbers (maybe a dial?), and have a 1/4" threaded opening. Two are newer, lighter metal, and have a made in Taiwan stamp on the bottom (those might be 1/8"?).
- Check and possibly replace the vents on the horizontal and vertical mains
My questions are:
-- First and foremost, is what's happening still in the realm of DIY maintenance, or do I need professional repair work?
If I can proceed on my own, I have these detailed questions:
- - Which tap is the lowest? There seem to be two that are parallel on opposite sides of the boiler.
- - How often should I be changing out the water on the boiler? I've seen advice from weekly to never.
- - how do I open the boiler itself to add a cleaning agent? should I do this at all - opinions on these forums seem mixed? How often should I empty and refill the boiler once I start this process?
- - what valves should I put on the radiators? Can I put a thermostatic radiator valve in the kids' bedrooms to allow them to adjust their own room temp? If so, which one?
- - I read that sometimes the mains in systems like this have capped and need to be vented, but I can't figure out which of the maze of pipes in the basement is the "main". It makes sense in the charts at the back of the book, but all the pipes downstairs are wrapped in silver insulation and the first floor has been converted to forced hot air, so it's visually very confusing to someone who doesn't know what she's looking for.
Here are some photos of the boiler, the pipes, and the valves:
Thanks so much! I've been really enjoying reading this site and getting to know the steam system inside my house.