Boiler sends up steam, water returns too slowly, low water cut off comes on too often

Raynic

Water level in steam gas boiler starts out with correct level of water in glass tube. As steam comes up water level in glass tube goes down until low water cut off comes on. Boiler stops, water slowly returns to boiler to correct level in glass tube, boiler starts. The process repeats it self every half hour or so. It seems water returns too slowly so there is not enough water in boiler thus kicking in the low water cut off. Once the water returns and there is enough water in the boiler it starts again. This is a three story townhouse. Could this have anything to do with the steam relief valves on the radiators?

moneypitfeeder

probably a clogged return

If you've got a wet return (lower than the waterline of your boiler) its probably clogged.  

gerry gill

ya, as moneypit says, it could be-

a clogging wet return, or bad near boiler piping, or dirty water in need of skimming, or probably a few other things if i think longer about it..can you post a picture of your boiler? is this a new boiler? is this an old boiler and a new occurance?

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

Raynic

Low water cutoff comes on too often

It's a 30 year old boiler steam gas.

This problem began afew years ago.

The piping did not change except a plumber installed a steam relief valve in the secondary return line.(This is a smaller diameter pipe 1" that runs along the ceiling in the basement and at the boiler comes straight down to join the std return line before it goes into the boiler.

The plumber put the valve at the junction where the pipe changes direction to go down to the std pipe (at an elbow at the ceiling level where the piping changes direction to go straight down to the floor to meet the std return pipe.

He did this because the water in the glass tube was bobbing excessively. 2 to 3 inces each way. It is not doing that now, just moving down slowly until it is below the fill line and activating the low watercut off. Other than that there were no changes in the piping. I drain the water from the boiler each year and once a week open the valve to let the dirty water out for about 5 seconds. So its a old boiler with a relatively new occurance. The fuel bills are high considering I am away most of the winter and the thermostat is set for 58 degrees. The bills are as high as a two family house my sister owns in the same neighborhood about the same sq ft . I am sure that this is because the system is turning off, cooling down and then heating up too often. I am trying to figure out how to send pictures from my digital camera.

The only thing I have done is change the steam valves on the radiators thru the years.

nicholas bonham-carter

slow to post

posting here is not instantaneous, and so that may explain your multiple postings, as you waited, then clicked again and again.

as the boiler builds pressure pushing down on the water inside it, the water level in the returns will rise 1.75 inches for every ounce of steam pressure. if your pressuretrol were malfunctioning, or the pigtail clogged, then the pressure may go up to 5 psi or more. i think you water is hiding in the returns stacked up to a height of 5[psi] X  16[ounces] X1.75[inches], which is higher than i can reach.

this may be where the water is, and it is also why we like keeping the pressure down to 2-8 ounces. this will require a good low-pressure gauge [gaugestore.com 1-3 psi], and a vaporstat [pexsupply.com].

as the pressure is so low, the main [not radiator] venting must be generous, and the radiator vents cannot do this job. good main vents are gorton#2.

see if the plumber can get the pressure down by installing the gauge and vaporstat which in your case may pay for them selves this winter! if you have a tight budget, then at least the gauge, and some more venting.--nbc

Raynic

too much pressure

Makes sense.

Question .

When the low water shutoff kicks in and shuts down the boiler it takes at least ten minutes before the water returns and the system goes on.

{ When I drain water from the boiler when it is off the water runs out. When I attempt to drain water when the system is on it sprays out (Under pressure)}

What if I I open the faucet to drain when the cut off switch kicks in. That should let out the pressure more quickly and the water return faster than 10 minutes. Granted I will lose some water in the process but I should be able to tell. What do you think? Would this be a way to see if there is too much pressure?

nicholas bonham-carter

hot water under pressure

the best way to start the diagnosis is with a good gauge.

i also hooked up a piece of clear plastic tubing to the return, and therefore could see the height of water in the returns. i found a horizontal part of the return just above the waterline, and as the pressure rose to 8 ounces, the horizontal hid all the water in the boiler. when off, it would take about 10 minutes to return to the boiler.

its never nice to around pressurized boiling water!--nbc

Raynic

too high pressure

I do not follow what you did with the clear plastic tube.

However, you do recommend a low pressure gauge and a vaporstat.

By the way the pigtail gets hot so I assume it is working.

If the gauge reads too high pressure then what?

What does the vaporstat do.

How can I tell if the pressuretrol is working.

moneypitfeeder

its starting to sound like

you might have a 2 pipe vapor system. (if it is you need your pressure at ounces) Typically, that (second return) is a dry return, however from your descriptions I'm a little confused. If it is a dry return (ie above the waterline of the boiler) it would generally take all the condensate from your radiators, drop down below the water line and join with the wet enter a hartford loop and into the boiler. If thats the case, then I don't think you should have a relief valve located in that line. The fluctuation you mention at the boiler water line sounds more like dirty, oily water. When was the last time it was cleaned, skimmed, and blown down? 

nicholas bonham-carter

pressuretrol testing

i suppose while the boiler is beginning to build pressure, you could turn the screw in the top to see if it cuts off the burner. there are 2 adjustments for the cut-in and cut-out, however it has been sometime since i had to adjust one, so maybe someone here can help us out with more precise instructions. basically you would be trying to see if the pressure adjustment will work by first turning down the screw to the cut-off point, and then turning in the apposite direction and seeing if the burner comes on again. this won't tell you what the pressure is, but will establish the basic function of the pressuretrol.

with the clear plastic vertical tube attached to the returns, the level of water in the tube is the same as the level of water in the returns. as pressure builds [4 ounces], the level in the tube will go up about 7 inches, so you can imagine what the level would be at higher pressures. this water is being "hidden" from the boiler, and in your case can shut down the boiler--inefficient.--nbc