What is this heating valve?

[Diezmon]

Hi guys,

I'm trying to figure out what kind of valves I have here. I have a hot water baseboard heating system. There are some valves in line that look like they're a shutoff/gate of some kind.

They say "THRIFT" on one side, and "B V 3/4" on the other. They use a standard screwdriver to turn them, and they'll turn all the way around, so I assume you turn 90 degrees for open, and another 90 for closed.

Look just down and to the left of the main shutoff wall switch in the pic. There are two of these valves next to each other on the vert lines.

How tight are these when closed, and what exactly are they used for?

Each zone has another valve at the end of it as well, with a lever for shut off.

The reason I ask: I need to replace my circulator pump, and am wondering if these little valves can be used to shut areas off, instead of draining the whole system.

Thanks,

Tim

[Rastus]

These look like balancing valves, maybe someone with more hydronic experience can explain further.

[Dr. Hardcrab]

"Diezmon" wrote

They look like (what I call) purge valves. Basically you use them by closing them off and bleeding the air out of the "loop". Strange thing is: I don't see the valve (usually a ball or gate type) that you open to GET the air out.

You can close them (usually by turning them 90 degrees so the "slot" is perpendicular to the pipe) and it won't let water through, but what about the OTHER side of the loop.

The best way to do it is to 1) turn the boiler off so it will cool down (run your hot water until it is manageable), 2) close every valve that you can find, 3) take the pressure off the boiler, 4) have the new circulator ready to go, and 5) have a wet/dry vac ready because you are going to have a lot of water. THEN you are going to need to know how to use those valves to get the air out of the system.

If you are not really sure about this, I would suggest you call someone in to do it. Best not getting stuck with no heat at this time of the year AND you will end up paying a lot more for a service call if you attempt it in the evening or on a weekend.

Good luck.....

[m Ransley]

It looks like a balancing valve that will shut off the flow ,but only a guess.

[Diezmon]

This is the kind of system you purge from the boiler. Each zone has a purge valve and shutoff at the end of the loop. These valves I'm wondering about are at the beginning of the loops.

Other side has another kind of shutoff valve.

I've already got no heat, that's why I'm replacing the circulator, which is not working. I'm really just wondering what these valves are for, and if they're pressure tight when closed. One of them is bad, so I need to get a replacement.

Tim

[Dr. Hardcrab]

"Diezmon" wrote

It's still messy, but if you close every valve you can, take the pressure off, you can do a quick swap out.

Put a bucket under it. Put a little pressure on the pipe (going into the circulator. Getting someone to help you is much easier) and remove/loosen the flange bolts. have a couple rags ready and stuff them in the flanges. Sure it's gonna leak a little, but it's better than a full-fledge flow.

[Bubba]

[mm]

I don't have hot water heat, but if I were closing every valve I could, I would make a list of every valve I closed, and what its position was before I started closing it.

It seems like there are too many valves to keep track of otherwise.

Remove NOPSAM to email me. Please let me know if you have posted also.

[Diezmon]

well bubba, the boiler setup was like this when we bought the house.

It's passed two inspections, so I'm going to assume it's ok for the code in my area :)

Tim

[Bubba]

[Dr. Hardcrab]

That's probably good idea. Especially if you have short-term memory and can't remember the 3 or 4 valves you close...

(not making fun of you.I HAVE to do that....)

;-]

[Shake-Hull]

[Bubba]

[Diezmon]

It is now, since I installed the new one.

[Diezmon]

I'm sorry you didn't like my response, Bubba. I don't know that you're the expert you say you are. You may be an expert at reading home improvement manuals for all I know(You're probably not, but you get the point).

-- "It may be just fine but it looks out of the ordinary to me."

So, you're not sure, but you're telling me that what my local guys say don't mean diddly?

All I can do is rely on the inspection we had, and a service call by a guy from a local heating place. Both of which said the system is basically ok, but could use some improvement. The heating guy did point out that it used to be an oil furnace, AND also mentioned the shaft direction of the pump, which I noted and subsequently fixed this weekend when replacing it. He had other recommendations as well... but since my post was about those valves, I didn't mention every other detail I had about the boiler and setup.

And yes, I do feel safe and warm in the house. Feel free to rip on me and throw your sarcasm my way. But, forgive me if I trust the heating guy who's telling me to my face more than a guy on the web I know nothing about.

Thanks for your input about the valves though, btw.

Pleasant dreams, of course.

Tim

[Bubba]

[mm]

What's probably a good idea?

I was fine until I was about 52. Now I'm 58.

Remove NOPSAM to email me. Please let me know if you have posted also.

[Geoman^^]

Good observation, Bubba. I didn't even look at that.

I started looking at this pick some more, seems they reduced from 1.25 or

1.5 off the boiler to 1". Also, they left the barometric damper on after the conversion, I wonder if they readjusted it to the Nat or Propane gas. This is NOT a problem if it was readjusted, as a matter of fact it would work better than a standard atmospheric flue diverter and can save you money over the standard diverter.

If this boiler doesn't have a backflow preventer on it you should put one ASAP. The code states you MUST have one, this will make sure you can't drink the water in the boiler under certain conditions within your home. The proper way to do this to and to pass code is to have a double check valve, the backflow preventer and then the pressure reducer valve. Does your boiler have these installed?

Rich

[Bubba]

Hey! Dont make me out to look like I know what Im doing. (Shhhhhh. You'll blow my cover).

I'll agree on the barometric, however, most manufacturers equipment recognize this as altering their equipment in a fashion that it was not intended for. Yes, it works but they dont like it. They is whimps! :-) Bubba

[Geoman^^]

Up until they had power vented boilers, I would always throw the diverter to the side and put a barometric in. Also, it really doesn't alter their equipment. I don't know if you realize it, but in the past before the HVAC trade became dumb, they would send you a draft diverter that was extra long and you, the installer, had to adjust the height for the proper inches of draft over fire. The old timers realized that every draft was different. They went to a fixed diverter because this trade became dumb and didn't know how to adjust the barometric.

If you ever get the chance to take Jim Davis's course do so. Even the reps at Bacacarach use him for advice, he goes over all this and tells how to really read the information that the Back 3000 and other are telling the service guy.

Rich