Steam Radiators

Sandra_5

The pipes are not insulated. They were but when we bought the house they removed the insulation because there was asbestos in the insulation.
It generally is on for 45 minutes to an hour at a clip.

Sandra_5

Steam Radiators

A new homeowner with a Steam Boiler (I have ordered the book). It seems that when my boiler kicks on, it is on for a substantial amount of time before it heats the house enough to kick off. Can anyone shed any light on how long their steam boiler stays on?
Just some general information, it is run on oil. It is a two floor house about 1200 Sq Ft.

Alan(OnVacationInOregon)Forbes

What

are we talking about here? Half an hour? One hour?

Are your pipes insulated?

Kool Rod

Hi Sandra- "I have ordered the book" -Great!-that would be the first thing I would suggest.

As to your question - There really isn't a "standard " on this as it depends so much on how your system is laid out and on the equipment used. One of the first things we need to know what type of steam system do you have? That is determined by seeing how many pipes lead to each individual radiator. There are "1 pipe systems" and there are "2 pipe systems. Let us know what type yours is as each type operates slightly differently.

It sounds as though you aren't too happy with the time it takes for steam to heat up your radiators. Generally there are some fairly easy fixes/adjustments that can be made to improve the performance of most systems and these fixes are detailed in "the book" so probably the best thing now is to wait until you have read the book and then we can discuss the fixes and help you from there.

What you might want to do while you are waiting for/ reading the book, is to time how long it takes your system to heat. In doing this you will have a basis to know whether any change/adjustment you make is an improvement or not. Ideally we would take the measurements from a "cold start" being where the system isn't still warm from the last cycle of the boiler. It doesn't have to be cold "cold" just reasonably cool. What we are trying to determine is how long does it take for the burner to heat the water to 212 degrees and make steam. We then want to time just how long it takes for heat (steam) to reach to each part of the system (radiators).

What I would do is make a list like the one below:

1.Burner Start Time

2. Boiler Piping

3. Mains

Then below this: list all the radiators in your house Assign names to them so you easily know what/where they are. Make room to take 3 or 4 measurements so we can determine an average time.

The first time measurement we want is how long it takes for the boiler to make steam. To determine this we pick a place on the bare pipe going from the pipes on the top of the boiler, up to the pipes that go along the ceiling of your basement. You want to take all "Boiler Piping" time measurements at this same location you have picked. We start the timing when the burner starts and stop the timing as soon as pipe, at this picked location, begins to feel warm as it indicates you are beginning to get steam.

Perhaps a WARNING here is in order. Steam pipes can get very hot (up to about 215 degrees) so be very careful when touching them. If you aren't sure whether the pipe you plan to touch is hot or not, try using an oven mitt first!

We'll leave the #3 "Mains " measurement until after you have read the book as it will be self explanatory by then.

The next measurements we want to get is the time it takes the steam to reach each individual radiator. We do this by feeling the pipe at the inlet to each radiator. We only time to the point where we feel the first definite change of heat as this means that steam is now reaching this point.
The time period taken is from when the burner first turns on and stops when we feel heat at the radiator. If the burner stops during this time period just make a note of it.
You might also want to make a note of how long it takes each radiator to get hot (warm to the touch at the opposite end of the radiator from the steam pipe) after steam has reached the radiator. These measurements will give us an idea of what needs to be done.

You'll enjoy "the book", "We Got Steam Heat". It's easy reading and crammed full of facts and explanations. For a homeowner not really familiar with steam heating reading it is like being in a dark room and then somebody turns on the lights. Boiler manufacturers should be required to include a copy with every steam boiler they sell as it would save every homeowner a lot of grief!

Just read your reply about insulation- Insulation would definitely help but we can discuss the "ins and outs" of this down the line.

- Rod

Jamie Hall

Pity

they removed the insulation. Asbestos is only a hazard when it is friable and dusty; everyone would have been better served had they encapsulated it. However, what's done is done. Step 1 is going to be to reinsulate all the steam pipes you can possibly reach. There are a number of good fiberglass products available, and it is a feasible do-it-yourself project. I'd be willing to bet that that will reduce the boiler run time by 20% or more, right there.

It is almost impossible to give a single answer to the time question -- there are just too many variables. So, some additional questions (not to be a pest, but to be helpful). How long is it between times when the boiler starts? How cold is it out when you are making these observations? Windy? Are these observations made when you are recovering from a temperature set back, if you use one?

For example: the system in the building I superintend (some 10,000 square feet heated) runs for almost an hour in the morning, recovering from a 5 degree night setback (60 F nights, 65 F days). On a normal winter day (about 20 F outside), it will run about 20 minutes, every other hour. Every hour, if its cloudy or windy; perhaps only twice during the day if it's really sunny.

That help any?

Sandra_5

Thank you both for your help. First of all please do not feel like a pest when you ask more questions, you have been very helpful.
It is tough to gauge how long it has been between boiler start times. When we first get home from work we turn the thermostat up about 4 degrees. It kicks on and is for about an hour. The rooms heat up so much that it usually does not need to turn on again until the middle of the night. The room generally gets about 3-4 degrees warmer then the thermostat is set for. When we go to bed we turn it back down. I have tried to notice (tough though in middle of the night) that it kicks on about 3:30 or 4:30am and every two hours after. While it is on it is on for about 45-50 minutes. It is about 18-20 degrees out.
And Rod, We have a single pipe system. I was able to track some of the stuff that you mentioned. The burner started at 6:31. It took about 35 minutes for most of the radiators to get hot. I have to try to get more specific measurements this weekend when I will be around the raditors more while the boiler kicks on.

Kool Rod

Hi Sandra- From you description it sounds like your thermostat might be a little off. You mentioned that you were "new homeowner" so I'm thinking that the walls probably have been painted recently so possibly the thermostat was moved in the process. Some of the older thermostats need to be leveled so if your thermostat was reinstalled slightly out of level that could be the cause for the thermostat being slightly off.

Can you tell us the make and model of your thermostat? Telling us the shape (round, rectangle) helps too! You might want to pick up a cheap thermometer just so you can compare it to the one on the thermostat.

Tell us a little more about the room the thermostat is in. Does it over heat or is it just the other rooms?

Are all your radiators heating okay?

From the sound of things your system seems to be generally working okay and probably just needs some "tweeking" to get it to its optimum.

One thing you might do is when the boiler is running and the rooms are already warmed up, before the burner shuts off, take a look at the gauge on the boiler and record what the pressure is.

Before I mentioned timing when the steam gets to certain places. As your system seems to be working fairly well you can hold off on this. Maybe just do one or two radiators like the one you think is closest to the boiler and the one farthest away. Also time how long it takes to make steam.
Remember to be careful of burns!

When you're reading up on steam, remember your system is a 1 pipe system as there will be notes specific to 1 pipe steam systems so while we are on the subject I will mention something about 1 pipe radiators. While you're looking at your radiators make sure the valves on them are fully open. (The valve is the "Tap" on the pipe leading into the radiator) These have to be full open or fully closed (preferably open)

They don't control the heat. Steam flows into the radiator and condensate(water) flows out, both sharing the same pipe. The water flows on the bottom of the pipe and the steam being a gas floats above the water. If you partially close the valve the water and steam try to go through the small remaining opening and collide. This causes "water hammer" (noise -banging). This is why the valve must be fully open.

It is also important that each radiator slopes toward the pipe. (meaning the end away from the pipe needs to be higher) This forces the condensate (water)to flow out of the radiator. You may find a little shim or block under the feet of the radiator on the end opposite the inlet pipe. It's placed there to cause the slope. Since the house floors may have been redone and the radiators moved, you might want to check that all the radiators have proper slope. This is easily checked with a bubble carpenters level. Don't rely on your eyesight to determine this. I have an old house and had a radiator looked like it had plenty of slope until I "bubbled" it and found the floor of the house had sagged and the radiator was actually sloped the wrong way!

After you have read "the book" things will come together for you as you will then familiar with steam concepts and terminology. Dan explains all this much better than I ever could. Anyway at this point just get familiar with your system. It might be helpful if you took some pictures of your boiler and the piping directly connected to it as pictures are helpful diagnosing any problems. Also a picture of one of your radiators from both ends. You will notice on the end away from the inlet pipe a fitting that looks like a bullet or a small alarm clock. This is the radiator's vent. It allows air to escape from the radiator but closes when steam reaches it. Well that's plenty for now

- Rod