normal water level and near boiler piping

dcbraley

I need some advice, I don't work on many steam systems but I have a new customer that wants me to get his system working better. Peerless oil fired ECT-04-125 with a McDonnell No 67 LWCO and McDonnell No 101-A auto feeder. The boiler overfills. I drained it and let it refill. The auto feeder doesn't shut off until the water level is above the sight glass. Is there some adjustment on the LWCO to establish the normal water level? Its and older steam system and this boiler was replaced at some point. The Hartford Loop centerline is an inch above the centerline of the top sight glass tapping. Could this contribute to the boiler overfilling? The system looks like its a one pipe parallel flow with dry returns that drop into about a 7' wet horizonatal return just above the floor.

clammy

Have you cleaned the float on the lwco ? If the boiler is surging ? A surging boiler might trip your feeder if the float is dropping to activate the feeder. Most residential really don’t need a auto feeder and older style can mask water lose and leaks and hi fresh water in take will shorten your boilers life span .i would also suggest to check the tds of your feed water and possibly add a demineralizer filter to lower the tds in your feed water . You may be better off replacing both the float stlye lwco w a electronic probe type and a hydrolevel svt auto feeder this way water use can be monitored w the gallon usage . Most float type lwco should be dis assembled and cleaned yearly weather a probe or float ,I usually recommend replacement every 10 years regardless of electronics or float it much cheaper then replacing a boiler ? Also make sure your pressuretroll pigtail is clean and not plugged and that your boiler pressure does not exceed 2 psi . Peace and good luck clammy

dcbraley

I haven't tried cleaning the float yet. I was there to replace some piping with pinholes in it. I haven't run the boiler yet to see if it surges. Its a vacation home so the owner isn't always there but the heat is left on so I think he wants to keep the auto feeder. I will recommend possible replacement with what you suggested. Is it okay to leave the Hartford Loop the way it is? Or should it be lowered?

clammy

Replacing pipe w pin holes. Usually There is a cause and effect loop going on ,pipes only get pin holes from a cause like wet steam no insulation no proper main venting , not enough pitch leaving pooling of water and possibledebrie and of course poor near boiler piping which is usually one of the culprit . If the Hartford loop ain’t bang and it a vacation home unless it’s making noise leave it if they want it right and are will to spend change it ,again flush ,wand and skim when done $ Peace and good luck clammy

nicholas bonham-carter

Clammy is right, clean or replace the LWCO, and then check the pressure, and make sure it is below 1.5 psi, verified by a low pressure gauge, (0-3 psi). Dirty water can also throw a lot of water up into the mains as it boils.
Higher pressure can also push up the water into the wet returns, which lowers the boiler water level, triggering the water feeder.
When the call for heat ends and the boiler stops firing, then the excess water returns, and floods the boiler.—NBC

dcbraley

Okay thanks for the help. The dry returns both had bad pitch and that was where the leaks were. I corrected that but It lowered the "A" dimension a bit. The replacement boiler was set up of the floor on solid cement blocks so that probably doesn't help the situation. There are two main vents on the dry return just before it drops to to the wet return. Both Vent-rite 77s. Look original, I will probably recommend changing them out. You can blow air thru them but not sure if its at the proper rate. You can see rusty water staining on them.

Jamie Hall

I don't think the 101-A has an adjustable feed. You could try replacing just the feeder with a VXT with adjustable feed (and a handy meter) and setting it for a long time delay and 1 gallon per trigger. That may help the overfeed problem which you are having.

Yes, the -67 is a float type, and yes it does need maintenance from time to time -- like cleaning the float and float chamber. It is possible that the float drops OK (easy to check, and should be) but hangs up on a rise.

EBEBRATT-Ed

Pin holes in the piping is a sign of too much make up water.
Sounds like the job has some issues

1. fix any and all leaks
2. Hartford loop is too high, should be 2-3 " below the boiler water line
3. Clean Low water cutoff and gage glass connections they could be partially plugged making the feeder not work right