Help identify this system ! (UPDATE 12.22 - repairs made. Isolating Issues)

TheMoneyPit

Hi everyone. 

Bought a house built in 34’ and have been learning the art of steam, even replacing a few warren Webster traps myself on some radiators. Here in St. Louis very few guys still alive and working on this stuff who know what they’re doing. Seeking help.

I THINK this is a steam two pipe system with dry returns. There’s a newer slant fin boiler here. Issue has been the boiler is over filling itself prob from a faulty return valve and thus water is blocking flow. The pressure control has probably also been turned up too high. I keep having to drain it and Have been letting the water drain in a trickle at the bottom of the loop.

The Webster vent trap being replaced  

The Webster boiler return being replaced 

Another view of the whole setup 

As you can see I’ve got a trickle coming out the bottom to keep it limping along and not overfilled.note - the auto filler was already replaced and isn’t faulty. Thanks for any opinions. 

Mike 

Steamhead

That's a Webster Type R Vapor system. Why are the vent trap and return trap being replaced?

First thing to do is replace that cute little Hoffman #4A on top of the vent trap. It's way too small to be the only vent in an entire system, as it is here. Use a Gorton #2. The system will heat much faster.

If the Return Trap is working, a Vaporstat isn't quite as essential, but I'd use one anyway.

neilc

that Ptrol is turned up too high,
dial it all the way down, till you feel a slight resistance,
inside the cover, make sure the differential wheel is set to 1,
if the boiler is off, does the gage return to zero?

neilc

at 5+ psi you're pushing water out of the boiler into the system,
then your feeder tries to refill,
then you get your flood,

there sre settings in the feeder to delay and limit the fill,
dial the pressure down first,
0.5 cut in,
1 differential, gives you 1.5 cut out,

Jamie Hall

That system was designed to work on no more than 8 OUNCES per square inch pressure.

If you haven't already junked the vent trap and the boiler return, don't. It will be remarkably hard to get the system to work properly without them. With them, shouldn't be hard.

You will need a vapourstat to control the pressure in the system. It should be set to 7 ounces per square inch cutout with a 3 ounce differential. A pressuretrol, even turned all the way down, is 3 times too much pressure for the system to operate properly.

If you get the pressure under control, the problem with overfilling may disappear.

Gordo

I would also advise you to completely remove the McDonnell & Miller 101A feeder. There is no delay built in to that feeder and when the LWCO calls for water, it will feed immediately and potentially flood/overfill your boiler.
It also has an iron body which rusts and causes it to fail and sometimes pass water into your boiler continuously.
You can manually re-fill your boiler when it runs low.
That can be a pain until you fix all of the leaks.
Once you get some control of water loss, you can consider getting a better type of automatic feeder such as Hydrolevel's VXT.

TheMoneyPit

Thank you guys! Will post back with results.

dopey27177

At the very bottom of the boiler return piping are two check valves.
These check valves may be worn out or the flaps are stuck or fell off.
These check valves were installed to prevent water from being pushed out of the boiler into the return piping which will cause the water not return into the boiler.

Look at the height of the Warren Webster vent trap and condensate pump. The are very high as compared to the boiler.

The reason for this is to allow the static head of the water to overcome the boiler pressure and re-enter the boiler.

This type of return system can only work on a vapor or very low pressure steam system.

The best way to have the system operate as intended is to install a vapor stat. Set the vapor stat at the minimum pressure needed to heat the house that would be about 8 ounces boiler off and and 4 ounces boiler on.

At that pressure if you repaired or replaced the steam traps they will last a much longer time because the steam in the radiators will be fully condensed most of the heating season and that means the steam traps will not cycle as much.


Jake

TheMoneyPit

Since I originally posted, a few repairs have been made to isolate issues which were spotted.

1 - the undersized vent was replaced with two new vents.

2 - the pressuretrol was turned down to lowest setting, with a 1 differential.

3 - the gauge was replaced and it is now properly showing "0" when boiler is turned off, not exceeding 2 psi even during longer runs, which is an improvement, I assume because its now properly vented. I know this needs a vaporstat to run at 8 ounces, etc...

4 - With this above, what's still happening is a very slow return whereby the low water system will feed the boiler mid run because condensate isn't getting back quickly enough to refill...thus it will flood itself by the time it 1 - refills and 2 - cycle ends and condensate cools, refills about 20-30 min later. THEN when it restarts on a thermostat call, its firing up with too much water.

(((COULD be the check valves at bottom of wet return as mentioned above I'll look into that)))

My guy tells me he now thinks the slow returns are because of a handful of clogged traps at 3-4 radiators. I do in fact have 2 totally cold radiators with a 3-4 others which are warm, but not really hot, compared to those which really kick off a lot of heat. This is a large house with about 20 radiators total. Could it be a handful of bad WW 02H traps are causing this slow return at large?

Of course the return lines probably have some mud in them too. But a few years we did not have this problem. Can only guess that some traps at radiators are slowly going bad and this is the correct next logical step to isolate before we open up return lines.

thanks

Michael in St Louis

BTW - anyone in this area who is a known "steam guy"?

EBEBRATT-Ed

there are a couple of MO contractors not sure about the steam aspect

mattmia2

It sounds like everyone is saying you need the vaporstat for the pressure in the boiler to be low enough for the water to be able to return to it.

Jamie Hall

Traps, as a rule, do not go bad slowly. They are pretty simple contraptions, after all, and they either work -- or they don't. Which is not to say that you don't have a couple of bad traps -- you may, and the 2 totally cold radiators may indeed be victims of traps which have failed closed (although there are other possibilities).

As @mattmia2 said, you may still be having a problem with excess pressure backing water out of the boiler, but usually that doesn't result in a slow return so much as a low water level which resolves very quickly once the boiler shuts off.

My I presume that what is happening is that the boiler shuts off on low water in mid cycle, the water feeder comes on, and the boiler starts -- and then is flooded when everything cools down at the end?

If so, is there any way to adjust the feed delay and feed amount on the automatic water feeder? Some do have that -- VXTs, for instance -- and some do not. If there is, I would suggest first setting the automatic water feeder to as long a delay as is available and a fixed feed amount -- start with 1 gallon, if possible -- and see if that doesn't cure the flooding problem.

Granted, this is treating the symptom, not the problem, but it will be a start. If you can, try it and report back, if you would.

TheMoneyPit

@Jamie Hall you are spot on here - "My I presume that what is happening is that the boiler shuts off on low water in mid cycle, the water feeder comes on, and the boiler starts -- and then is flooded when everything cools down at the end?"

Don't have a controller with a delay ability at moment. I'm going to get the vaporstat as the next step and address the few bad traps at radiators. Will report back.

JUGHNE

As Jamie said traps are either good or bad. Usually fail closed.

They must pass air until steam gets to them and then your rad would be hot.
Then they must drain water and close again...and not let steam pass into the dry return.

If your cold rads have a hot trap pipe below it, it could be because another hot rad trap failed to close and lets steam into the return to close the good trap on the cold rad.
So you need to temp check the output of all the traps to see if they are passing steam into the dry return.

IMO, failed rad traps would not delay return water.
Most likely slow clogged piping or those check valves on the return.

TheMoneyPit

Morning -

Two new vents (see new brass vents at top of setup in pics below). Just checking with the pros here that these are sufficient and righted sized.

I'm still having the overfill problem but at least with the better venting the amount of overfill is less.

Do these warren webster boiler return traps go bad or need servicing? (the football sized item 2/3 of the way up?)

thanks

Vaporstat on order...

KC_Jones

What vents are they?  They don’t look like any steam vent I’ve ever seen.

Brand?  Model #?

EBEBRATT-Ed

@KC_Jones
I was thinking the same thing

Steamhead

They're not Gortons. I've seen that shape before- Marsh?

TheMoneyPit

so they are made by marsh steam...here they are....

http://www.marsh-steam.com/pdf/air_vents_5_55_50.pdf

http://www.marsh-steam.com/popup_airvents_series.html

Steamhead

Didn't realize Marsh was still in the business. However, those vents don't have much throughput- according to @gerry gill and @StevePajek 's chart, considerably less than a Hoffman #4A.

Get a couple Gorton #2 vents and put them on. Each #2, according to the chart, is well over 10 times as fast as the Marsh vent. Watch how much better it works.