King Valves for Blow downs...Worth It?

AdmiralYoda

Hello all, I'm planning to repipe my boiler in the spring.  I'm wondering if King valves are worth it for blow downs.

Does the cost of the king valves on the risers and the mains and isolation valves for the safety devices justify the cost and complexity?

It's a well maintained residential boiler and is skimmed and drained regularly and it's always pretty clean.  Will a true blowdown with king valves be worth it?

EBEBRATT-Ed

Probably not, but they are nice to have

JUGHNE

Everyone of them I have come across will not operate, even after only 20 years.
If operated every year probably would be OK.
I imagine they need to be steam rated $$$.

And no safety devices should have any isolation valves on them for obvious reasons.
Return line valves would be handy for flushing.

ethicalpaul

I put them on my supply risers but that was only to be able to test one or the other riser. Totally unnecessary.

On the main is OK if you want to build pressure in the boiler for whatever reason (like to test your controls, or for blowdown) but you also need one on the return otherwise the pressure will push the water out the back.

Funny story, I didn't put one on my main yet, so if I close the 3 I do have, then the pressure goes from the return up the equalizer to the main and pushes all my boiler water immediately into the main. You learn not to do that pretty quickly LOL

Brass or even SS ball valves aren't that expensive and I think they will stay operational for many years even without exercise.

mattmia2

Maybe if you do it you should invest the extra bit in a flanged valve or some flanges or unions so you can take it out to free it up or replace it when it doesn't work.

Ron Jr._3

If the King valves are there just to test pressuretrol settings , I'd just invest in a 2nd pressuretrol . 

ethicalpaul

That can be one of their purposes. Is your thinking that having two pressuretrols means you never have to test them again? You must be a building superintendent

ChrisJ

ethicalpaul said:

That can be one of their purposes. Is your thinking that having two pressuretrols means you never have to test them again? You must be a building superintendent

He installs boilers in some of the most cramped closets I've ever seen.

He deals with customers all day long.



For me, I rarely use my king valves.  I find a wand does a far better job at washing things out once a year.

New England SteamWorks

We find them incomparable when performing annual maintenance, and well worth the cost and expense.

ChrisJ

New England SteamWorks said:

We find them incomparable when performing annual maintenance, and well worth the cost and expense.

You feel a wand doesn't work as good?

JUGHNE

New England SteamWorks said:

We find them incomparable when performing annual maintenance, and well worth the cost and expense.

Key words annual and maintenance assure that they will continue to operate, unlike all that I have come across.

Maybe they do the wand also.

GregWeiss

They leak