Change circulator pump and flo control valve

mmc239

after I shut the valve to left of flo control valve. How much water should drain out of spigot below flo control before I change circulator pump and Flo control valve?

GroundUp

That depends entirely upon what's on the other side, but there will almost certainly be much more once you break the flanges loose. Get a bucket or tub below the circ after you get everything out of the drain, and catch the remaining water in there. Obviously close the nearest valve(s) to the right as well.

mmc239

should I connect a hose to it and drain it? Is the water that being drained out of it from the boiler or the radiators upstairs?

hot_rod

you need to isolate both sides. It looks like an air purger to the right

mmc239

this is the other view. How would I isolate the other side?

hot_rod

a larger view of the boiler piping. Any valves on the return to the boiler?

hot_rod

or get rid of the flo control valve , use a pump with the internal check, and you have room to add a ball valve on the other side of the pump

EdTheHeaterMan

You may need to drain the entire system if you can't find another valve.

Got a picture of the piping where the yellow arrow is pointing? Maybe you could step back about 10 feet and we can see the BIG picture!

HVACNUT

What's the PressureTrol for?

mmc239

mmc239

the boiler is a steam boiler that has a coil and is split so two room on the house run off hot water baseboard.

if I close valve next to Flo control and hood a hose up under it, will that drain the water out of the hot water baseboards only and not the boiler?

HVACNUT

So you need to shut off the valve feeding the coil loop first, if there is one.

mmc239

where would I find that valve? If there is not one, how would I isolate?

GroundUp

The system is a loop. If you simply close one valve, all the water will drain from the other side. Follow the piping on the other side and look for a means of isolation. If there aren't any valves, you will have to drain everything above the level of the pump.

EdTheHeaterMan

WOW. Talk about the big picture! You have a steam boiler with a hot water loop from a tankless coil. Your steam boiler does not have water filled radiators. So you will not be draining any water from the steam radiators in the system. The baseboard radiators are the only water filled radiators. Are those baseboard radiators located above the circulator pump? Then you will need to let the water out of those radiators. If you don't, then it will all spill on the floor when you remove the circulator pump.

That may make a mess for you to clean up. If all the baseboard radiators are below the circulator pump, then you only need to drain the water in the system to a point below the circulator pump.

Now I see 2 things wrong. Well actually one thing wrong and one thing I don't see. The location of the water temperature Aquastat should be in the boiler, not that pipe on the tee the temperature probe is barely touching the water that you want the temperature of. poor design. It would be like taking your temperature with an old mercury thermometer by placing it on your finger tip. You might get 89.6° there. Not 98.6° That probe should be in the boiler!

The other thing I don't see is a relief valve. You need 2. I see the steam boiler relief valve, I don't see the water system relief valve. That water side is a closed system that has an expansion tank, heat source (the coil) and is filled with water that can expand. If it expands into a failed expansion tank that has no room for expansion, then the pressure can get well above 300 PSI if there is no relief valve. If I were your service technician and did not see a relief valve on that closed loop, then I would turn the switch off and instruct you not to operate this system until you get a proper relief valve.  

EdTheHeaterMan

You may have a relief valve. need a better picture of the part with the yellow tag.

mmc239

this is other view

mmc239

also have these at bottom of loop…