return lines testing

mrspeeder

Hi,

new to the forum. Our oil boiler(also feeds hot water)was flooding, not sure what the super did. We changed the float and now the water level has been stable. We haven't had the boiler on for long except to give hot water. The plumber is pushing to change the return lines but I want to check them first as it is a huge expense. Is there a way to test the return lines or even put a camera in there? I was thinking maybe just change the return lines by the boiler only as that is the lowest point. We will also change the pressuretrol, pigtail, gauge

Any thoughts would be greatly appreciated.

Thanks

EdTheHeaterMan

As you would a straw from your soft drink, you can blow thru it to remove the paper cover and send it jetting across the table to hit someone on the other side. If the straw is blocked, nothing will move. partially blocked and the air will move slowly (and the paper cover will just flop off the end and drop to the ground right in front of you). So how might you accomplish this on the pipes with all the elbows and turns? (see that, I made elbows and turns sound like 2 different things) You will need to open the pipe at a tee cap (or plug) left in the piping for just this reason and run a snake thru the pipe then stuff a garden hose in there to flush all the scum that the snake just loosened up.

Another way is to cut the pipe up high, where you want to start the inspection (or unscrew a union if available) and open the service valve, cap or plug at the lower end of the pipe and see if the water will run thru the pipe freely or if it is sluggish or even blocked. sometimes this service is easy because some dead man thought you might want to do this after he is dead. Other times you need to make your openings where they are needed. Sometimes you can reconnect with a radiator hose (like the ones on automobile radiators) for a temporary repair. Then in the off season replacing the cut pipe with something more permanent that can be easily serviced in the future.

JUGHNE

Are the returns under the floor?

How much of them are always full of water?

How about some pictures showing all the piping.

Is this a home, apartment or condo?

mrspeeder

I have to take some pictures, but the returns are overhead in the basement and go into a hartford loop. It's for a 3 family home roughly 2500 sq ft. I'm not sure if the return was full of water but the boiler was. 

Jamie Hall

Is this one pipe of two pipe steam (one pipe has one pipe to each radiator, and vents on the radiator; two pipe has two pipes -- one high and one low -- at each radiator). It makes a big difference as to the actual function of the pipes to which you are referring as returns.

In any case, it makes little difference as to replacement -- if they aren't leaking, they don't need to be replaced.

mrspeeder

it's one pipe. The plumbers whole thought process is the pipes are old and they may calcified inside the pipe, I don't disagree I would just like to check. I come from a Automotive background so, I always test and verify before I change anything.

Jamie Hall

In theory, then, none of those pipes should have water standing in them -- just the trickle of condensate when the boiler is actually running. The result is that they don't usually have much build up in them. Which is not to say that they can't and sometimes do rust, if there are places where the condensate can't drain freely.

Bottom line: if they aren't leaking somewhere, they shouldn't need replacing. Not unusual to have steam main extensions -- never mind steam mains -- last a century of so.

VincentAlbi_2

I am not a plumber but have had to figure out issues with steam systems. I have learned alot from this site. If your loosing water the auto make up water kicks on. The 2 main reasons are a leaking return usually underground or the boiler is leaking. Do this fill your boiler to the line on your site glass. If you did not mark it do this. With boiler on "calling for heat or thermostat set for heat" open drain down till boiler goes off on low water cut off. Now open feed or press button on the automatic feed.Watch where the water line is and mark the tube when boiler fires up. Shut feed. That is your water line. Shut the boiler off.Now observe if it starts to fall. If you see the water level drop and no water around the boiler it is your return line. If you start the boiler and observe water dropping  you may have a leak from a section of the cast iron. You won't see any water because it is turned to steam and goes out the chimney.  Look for white vapor. Most leaks in the returns are from the buried pipes on old systems. If returns are narrowed and you can't clean them you will have to replace them.Above floor returns not as costly as below.

mrspeeder

VincentAlbi_2 said:

I am not a plumber but have had to figure out issues with steam systems. I have learned alot from this site. If your loosing water the auto make up water kicks on. The 2 main reasons are a leaking return usually underground or the boiler is leaking. Do this fill your boiler to the line on your site glass. If you did not mark it do this. With boiler on "calling for heat or thermostat set for heat" open drain down till boiler goes off on low water cut off. Now open feed or press button on the automatic feed.Watch where the water line is and mark the tube when boiler fires up. Shut feed. That is your water line. Shut the boiler off.Now observe if it starts to fall. If you see the water level drop and no water around the boiler it is your return line. If you start the boiler and observe water dropping  you may have a leak from a section of the cast iron. You won't see any water because it is turned to steam and goes out the chimney.  Look for white vapor. Most leaks in the returns are from the buried pipes on old systems. If returns are narrowed and you can't clean them you will have to replace them.Above floor returns not as costly as below.

Funny you mentioned this, I actually had the plumber check if the boiler was good. He saw the boiler was flooded and immediately said return lines and I said wait let's see if the boiler is good. So we drained the boiler completely out, it took a few gallons and we emptied it out. We watched the feeder kick in, but it didn't kick in enough to get the boiler to turn on, so he stated it was the float. We put in a float and the water level came up to the right spot and the boiler turned on. Ever since that day the water level has been stable and it's been on a few times to feed hot water. We didn't let it drain while the boiler was running, we can try this next.

We will now do a complete maintenance to the boiler, clean it out, change the nozzle to factory specs, change the pressuretrol and pigtail along with gauge, change the fuel pump strainer, oil filter and flush the return lines, clean out the sediment in the water feeder. We will also see when it's cold and the boiler is on for a long time what happens and go from there. All the return lines are above ground and into a Hartford loop.

VincentAlbi_2

If your system does not have any underground returns but boiler floods then it could be that the returns are very scald preventing the condensate water returning to the boiler fast enough.The auto feed may kick on to make up water then the slow condensate water returns. Also not many systems have a Hi water cut off which is why you need to mark your water boiler line. The super may have overfill the boiler if done by hand.If you look at the diagram of a one pipe steam system you will see the return does have water in it..the same level as the boiler and site glass.