VECO Vapor system

Paul S_3

just left a job in brooklyn nyc.....Customer complaining of overall poor system operation, water hammer in mains, overheating of rooms etc.....i believe its a VECO vapor system, because out of 30 or so radiators/baseboard 10 of them have return elbows that say VECO on them , i looked it up in the lost art book. the boiler is 650,000 btu weil Mclain , it has 2 3'' heat timer motorized valves not dripped before valve....valves are about 4 feet from boiler.....the other radiators/baseboards some have steam traps and some have simple return elbows (i know some may have orifices) and there are a few baseboards that have just one pipe to them??? all radiation drains into dry return then into wet return by boiler....question is how can all this work together ? some have traps , elbows, one pipe steam, and the VECO return fitting. pressure for boiler is set to 3psi.....what i would like to do is add a HEATTIMER or tekmar to run boiler and install TRV'S ....I will be going back in a few days to go over system alot more....any advice thanks paul s

Paul S_3

VECO pics

Pics

Paul S_3

more

More pics

JStar

VECO

First things first. CRANK IT DOWN! VECO systems need to run at 3 ounces in order for the return elbows to work properly. The water hammer may go away at that point.



The zone valves may not need drips if they can drain back to the header properly.



Is that an air vent on one radiator?

Paul S_3

thanks

Jstar.....thanks for reply....I did crank pressure trol down....it's operating at.5-1.5....I will be going back soon to see if it helped.....EVERY radiator/baseboard has a air vent....I guess they did it because steam was getting into returns??....some rads have traps some have VECO return ells....thanks Paul s (how do I know if water is draining into header from motorized valves?

JStar

VECO

Even 1.5 lbs is too much. They need a Vaporstat or the system will never operate correctly. I bet that once the pressure is lower, the traps will start working and the air vents can be removed. If there are still problems, test the traps that have elements.



The zone valves will need to be dripped if they cause hammering soon after they close.

Paul S_3

ok

Will get vapor stat....and when I drip motorized valves I just drop into wet return? Do I need f&t trap? Thanks Paul s

JStar

Valves

You only need a trap if it ties into a dry return. You can drop into a wet return if there is enough A Dimension from the water line to the drip connection. At 3 ounces of operating pressure, that shouldn't be a problem!

Paul S_3

but

What about those rads with the return ells....chances are they have orifices in them? And those VECO fittings....I know they have no moving parts but of something were to happen like a clog a simple trap can take it's place? And just so I know how can a one pipe radiator work on a two pipe system?I have a few here thanks Paul s

JStar

Rads

The return elbow forms a water-seal trap. There is no orifice. Any orifices would be in the supply valve, but the VECO valves had none. You can replace them with modern traps. Just be sure to send me the original! I'll put it in my own house.



One pipe can be mixed with two pipe, but it has to be done with care. Typically, that's not the case.

Paul S_3

return ell's

I meant that some rads have what looks like a simple radiator return elbow with spud, no VECO fitting, Paul S

JStar

Orifices

It's easy enough to crack open the valve union to check for an orifice. The radiator will act like a normal two-pipe radiator with a trap.

Paul S_3

JSTAR

this system has HEAT TIMER steam zone valves(power open/power close), they have very bad control in building. i would like to use the TEKMAR 279 steam control at this job. i know this control can operate zone valves...what do you recommend , removing valves and using this control ? or using 2 of these controls to operate each valve? im going back tomorrow to install 2 vaporstats inplace of the 2 p-trols that are there now. and soon will be replacing all traps / vents....removing radiators vents....and installing TRV'S at every radiator..all together there are 3 p-trols, one being manual reset,what is the 2nd p-trol for?...thanks Paul S

Paul S_3

VECO

Anyone have any insight? Thanks Paul s

JStar

TEKMAR

I don't think that control can handle a power open / power closed valve. Only a spring closed valve. Haven't seen it in a while, so I'm not 100% positive, but that's what the literature looks like. You can still use it for the system though.

Paul S_3

2nd ptrol

And what do you think the 2nd ptrol is for, there is 3 all together, 1 manual reset, and 2 standard ptrols Paul S

Paul S_3

VECO

i went back and installed vapor stat (4oz-12oz)....i traced out piping, there is 2 3'' mains....neither have any main venting or any crossover traps...both mains end and drop into a wet return. should i add main venting? Every radiator has a air vent, there are 3 dry returns where all radiators drain into, neither return has any venting, it looks like all dry returns end up in boiler room where piping was replaced during boiler install, if i remove radiator vents, i have to add vents on return, returns in boiler room drops into common wet return....thanks Paul S

JStar

Pressure

The extra Vaporstat might be a redundant control, or set up to handle High/Low firing. Is there a high/low burner?



I would definitely add venting on the dry return after all of the returns tie together. I guarantee the lack of vents are the reason for the radiator vents. The original VECO system would have vented into the chimney from the Pressure Governor.

Paul S_3

no burner

Theres no burner, it has a gas train, I believe just on/off, I will look tomorrow when I go back. I dont know if this can help but all 3 ptrols are wired in series , thats why I dont understand the 2nd one, they all interupt power to gas valve. And there are some radiators without a trap, just a regular return elbow, I opened the union and checked inside, im giung to add traps there. Thanks Paul S