Check valve with low cracking pressure

dopey27177

I found a check valve with low cracking pressure that can be used in both horizontal and vertical positions that can be used on vapor systems.

Can be used as the main vent for vapor vacuum systems or put between the main vent outlet and vents valves.

economical cost and can help restore a system to operate on vacuum.


Jake

Chris_L

Hmm. That valve doesn't even open until 1/2 psi, according to the spec sheet: https://www.americanvalve.com/perch/resources/g31slspec.pdf

I'd say that is way too high to put inline with a vent.

dopey27177

Hy Chris

Many of the vapor systems cannot be restored to original operation.

These systems that have been bastardized can operate below 1 PSIG.

Settings for steam pressure can be set to 10" with a drop back of 4".

I know the cracking pressure is .5 psi

At 10 " psi we are above the cracking pressure and with the check valve opening and discharging air the system is OP.

Key to this conversation is if the piping system is tight the system will operate operate with vacuum whereby for a short period of time steam will be produced at lower temperatures.

The best part of this is fuel consumption will drop a bit.

As trouble shooters and heating professionals our job is to find ways to to get the most out these ruined vapor systems.

Jake

The Steam Whisperer

Try Apollo Part no 61-104-A1 This has a cracking pressure very low, but needs to be installed vertically. Gravity holds the ball in place.

dopey27177

The check valve can be installed horizontal or vertical.
I know appolo valves very well. used a lot of stainless steel valves in my time.

Jake

ethicalpaul

The Apollo Part no 61-104-A1 seems to be .5 psi cracking pressure, I don't consider that low

I'd love one that is just a gravity ball with no spring

Jamie Hall

With all of this, it's really important to remember that if you are dealing with a vapour steam system, the steam main pressure should never exceed 8 ounces gauge, and usually less. If the system is piped with crossover traps, as many were, the pressure in the dry returns should never exceed atmospheric (0 ounces gauge) and the main vents on the dry returns should never close (some vapour systems had just an open pipe vent, usually into the chimney). If you really want these things to work as intended, and you also want to allow them to drop into a vacuum, then you really do need to use main vents designed for the purpose. Unfortunately, the big old Hoffman #15 just isn't made any more, but the Hoffman #76 is and several of them can be ganged for the purpose. They're not cheap...

The Steam Whisperer

The 61-104-01 is 0.5 psi and uses a spring. The next down is 0.2 psi. The A-1 model is lower yet and has no spring, it must be used vertically with the ball on top since gravity is the only thing closing the valve. Used horizontally, the ball will open and then just stay open. I have one sitting right here on my desk.

ethicalpaul

That sounds great. All the internet information I could find on it said .5 psi.