buying a vaporstat

Unknown

They are considered as safety items, and are not available at retail. An authorized Honeywell distributor will not sell them to homeowners, you will need to find a contractor and have it installed. Use the "Find a Contractor" feature on this website, or find a steam-savvy pro in your area.

james_27

buying a vaporstat

Fellas,
I am looking to buy a vaporstat for a one pipe steam system.
What would the model to buy be?

Would running a vaporstat reduce the speed at which the radiators vent air?

Brad White_203

Venting speed

It is a bit of a paradox but the higher the available pressure behind the vent, the faster your system will vent. Yet, the lower the steam pressure is, the greater the volume, hence the faster it will move...


Bottom line is, yes, if you have an ounce of pressure behind a vent it will release X amount of air. If you triple that pressure, it will release about twice that amount, so it is not linear.

What most folks find when replacing a pressuretrol with a vaporstat, is that the newly reduced cut-out pressure is reached too soon before the air gets out, due to back-pressure. A more generous (and thoughtful!) venting strategy is necessary in most cases.

I would get Gerry Gill and Steve Pajek's e-book, "Balancing Steam Systems using A Venting Capacity Chart". Very handy and the proceeds go to a good cause.

David Nadle

No

There's a mental/verbal shortcut that happens in a lot of postings on the Wall about "turning your pressure down," as if the pressure limit switch controls the fill pressure. Not so.

All a vaporstat will do is change the pressure the boiler shuts off at. Instead of a minumum of 1.5 psi, you'll be able to shut off at much lower pressures. It will have no effect on venting speed. But if it takes less than 1.5 psi to get steam to every last vent, you'll save money with a vaporstat.

You probably need the 0-16 oz model with break and make, but you gotta know what you're doing and understand your boiler schematic first.

Chris M_2

Finding a Steam Pro

How do I find a steam pro in the Northern Westchester area? It seems too easy for anyone to call themselves a steam pro, just because they install boilers, which seem mostly to be hot water systems, from what the pros around here seem to spend most of their time selling and servicing. I need someone who can come to my house because they know steam systems, not know OF steam systems. Is there anyone out there?

james_27

Vaporstat still a question.

Thanks for the input fellas but the question was not answered.
WHAT WOULD BE A GOOD MODEL # OF VAPORSTAT TO BUY?
The installation and buying of the product is not the issue here.

Brad White_203

Honeywell L408J 1025 Vaporstat, 0-16 oz, mercury-free

aaa_2

aa

Brad ,
Thanks. As always, you have the answer.

donald@donaldluckenbill.com

Brad, what do you suggest in terms of a vaporstat that goes over 1 psi?
are the hookup generally the same? connect red/black wires?
Thanks.

Brad White_203

Honeywell has

a similar model that goes between 0 and 4 PSI. I refuse to tell anyone how to wire anything... (RTFM and all that, things change, so go by what they tell you). You can wire them as high limit and low limit controls though.

I would specify the 0-4 PSI model on a single commercial boiler but prefer the 0-16 ounce operating range for most houses. Most of my commercial work has multiple boilers so therefore has a control panel to orchestrate them. With those panels comes a pressure transducer and variable analog signal, so a vaporstat never finds it's way to the job.

scrook_2

Honeywell Vaporstats

See:

http://customer.honeywell.com/techlit/pdf/PackedLit/65-0287.pdf

Note that L408J1025 (& L408J1033) MAKE on pressure rise ONLY.

The L408J1009 (0-1 psi) & L408J1017 (0-4 psi) are full SPDT so can BREAK on rise, and/or MAKE on rise.

As a matter of interest, the old style Hg switched L408A, L408B & L608A Vaporstat data sheet may be found here:

http://customer.honeywell.com/techlit/pdf/60-0000s/60-2158.pdf

donald@donaldluckenbill.com

Scrook, im trying to connect a vaporstat to control the current high pressure on my one pipe steam.
So should i buy either one of "the L408J1009 (0-1 psi) & L408J1017 (0-4 psi) are full SPDT so can BREAK on rise, and/or MAKE on rise"

trying to understand your terminology.

Thanks

Steamhead (in transit)

the L408J1009 (0-1 psi)

is the one you want.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

donald@donaldluckenbill.com

Thanks.