Steam Vent Summary Table
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Steam vent types:
Two-pipe steam heat vents vs one-pipe steam heat vents: this article gives a table of the Summary Of Types Of Steam Vents On 1 & 2 Pipe Steam Systems.
We also provide a Steam Vent Product Cross Reference table for further information on steam vent replacement.
Our page top photo is a Vent-Rite # 11 steam vent intended for 1 pipe steam systems.
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Steam Vent Summary Table, Cross References, & Sources
At left is the Hoffman No. 41 is a steam vent . The mounting method of a vent varies and is a reason for making sure you have the right replacement steam vent.
The information in this article will assist you in selecting the proper replacement steam vent for your 1 or 2 pipe steam heat system.
Watch out: If the radiator continually makes noises (whistling or wheezing) at the steam vent, there is a problem that needs to be fixed: a bad steam vent, steam piping problem, steam pressure set too high, or boiler oversized for the heating distribution system.
Watch out: Be sure your steam heating system and its controls are properly adjusted - excessive steam pressure can be dangerous.
[Click to enlarge any image]
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Summary of Types of Steam Vents on 1 & 2 Pipe Steam Systems
The following tables are adapted from product literature provided by Emersonswan.com, a provider of Vent-Rite steam vents for radiators, convectors, steam risers, main steam vents and vents for unit heaters.
Table of Non-Vacuum Vents & Their Applications & Substitution Part Numbers |
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Application |
Product Number |
Connection |
Vent Port Diam |
Operating Pressure 2 |
O.A. HT. |
Adjustable? | Substitutes For |
| Vent-Rite vents for Free-Standing Steam Radiators |
No. 1 |
1/8" Male NPT |
3/32" |
3 psi |
3 1/4" |
Yes |
Dole #1A Hoffman# 1A |
No. 11 |
1/16" |
6 psi |
2 3/4" |
Dole #1933 Hoffman#40 |
|||
| Vent-Rite Convector Heaters Steam Risers |
No. 31 | 1/8" Male | 1/16"1/16" | 6 psi | 3 3/4" | Dole #3A Hoffman# 41 |
|
| No. 33 | 1/4" Male | Dole #3B Hoffman #43 |
|||||
Vent-Rite |
No. 35 | 3/4" Male x 1/2" Female NPT | 3/32" | 3 psi | 3 1/4" | Dole #4 Hoffman #45 |
|
| No. 75 | 5 psi | 4 5/8" | Dole #3C Hoffman #45 |
||||
| No. 77 | 1/8" | 3 1/2 psi | Dole #5 Hoffman #45 |
||||
| Vent-Rite Unit Heater Steam Vents | No. 57 | 3/4" Male x 1/2" Female NPT | 1/32" | 20 psi | 4 5/8" | Dole #55 Hoffman #77 |
|
| Hoffman Steam Air Line Valve | No. 3 | ||||||
| Hoffman Steam Vent - radiators | No. 40 | Angle - Side Inlet | 1/8" | 6 psi | |||
| Hoffman Steam Vent - convectors | No. 41 | Bottom Inlet | 1/8" | 6 psi | |||
THERMOSTATICALLY-CONTROLLED STEAM VENTS No-Float type vents |
|||||||
2-Pipe Steam Radiator Valves & Traps See |
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Notes to the table above
1. Adapted from "Air Valve for Steam Systems", Emerson Swan (Vent-Rite), Vent-Rite Valve Corporation: 1875 Dewey Ave. Benton Harbor, MI 49022 TEL: (269) 925-8818 FAX: (269) 925-7888 retrieved 2/28/2014, original source www.emersonswan.com/ckfinder/userfiles/ files/Vent-Rite%20Literature%281%29.pdf
2. Operating pressure drop ("drop away") is the maximum pressure at which the vent will continue to open and close due to the change of temperature.
The vent may be used with slightly higher pressure provided it drops below the operating pressure between each firing cycle.
Steam Vent Product Cross Reference
Steam Vent Cross Reference / Substitution Chart |
||
| Eaton / Dole | Hoffman | Vent-Rite |
| 1A | 1A | 1 |
| 4 | 45 | 35 |
| 3A | 41 | 31 |
| 3B | 43 | 33 |
| 3C | 45 | 75 |
| 5 | 45 | 77 |
| 55 | 74 | 57 |
| 1933 | 40 | 11 |
Notes to the table above:
Watch out: be sure to review the manufacturer's specific details before attempting to swap steam vents. Other manufacturers will have additional steam vent cross-reference charts; do not attempt to remove a steam vent if you are not properly trained as you could be badly burned or injured.
Some of these steam vents work on either 1-pipe or 2-pipe steam systems while some others such as the Dole (now Eaton Steam Vents) 80 / 85-series steam vents are for single-pipe steam systems.
Steam Vent Manufacturers, Installation Instructions, Repair Guides
Illustration: Dole 1933A 1/8" NPT Angle Steam Vent
- Armstrong, Rv-4 One-Pipe Steam Radiator Valve [PDF] available from Armstrong International,
816 Maple Street, Three Rivers, MI 49093 USA, Tel: (269) 273-1415, Armstrong has offices in Beijing, China, Belgium, India and Mexico. Web search 12/27/2010, original source:
http://www.armstronginternational.com/thermostatic-valves-rv-4-one-pipe. - Barnes & Jones Corporation, 91 Pacella Park Drive Randolph, MA 02368, Tel: 781-963-8000calibrated steam traps and vents, Website: http://www.barnesandjones.com/Email: bnesbitt@barnesandjones.com. Vent-Rite steam vents for radiator control.
- Eaton - Dole® AIR VALVES for STEAM & HYDRONIC HEATING SYSTEMS, Siebe Appliance Controls, Laundry and Specialty Systems Division, 191 East North Ave., Carol Stream IL 60188 USA Tel: 800-332-4643
- Eaton - Dole® AIR VALVES for STEAM & HYRONIC HEATING SYSTEMS, W.R. Wallin Associates, Website: wallinassociates.com retrievfed 2020/02/28 original source : http://www.wrwallin.com/yahoo_site_admin/assets/docs/Tunstall.7975833.pdf
Note: Dole air and steam valves are now handled by Eaton - good luck finding the company's contact information, but you can find the products at your local plumbing or heating supplier. - Energy Savers: Heat Distribution Systems, Steam Radiators & Hot Water Radiators, [PDF] U.S. Department of Energy, web search 12/27/2010, original source: http://www.energysavers.gov/your_home
/space_heating_cooling/index.cfm/mytopic=12580 - Gorton Heating Corporation, 546 South Avenue East, Cranford, New Jersey 07016, Tel: 908-276-1323, email: info@gorton-valves.com, Website: http://www.gorton-valves.com/ fast venting valves for steam heating systems.
- ITT Hoffman Specialty STEAM VENTS for RADIATORS MODEL 1A 1B AIR VALVE INSTALLATION INSTRUCTIONS [PDF] (2007), ITT 8200 N. Austin Ave. Morton Grove, IL 60053 tel: 847-966-3700 fax: 847-966-9052 www.hoffmanspecialty.com
- Hoffman 1A ADJUSTABLE STEAM VENTS [PDF] Hoffman Specialty, ITT, web search 12/27/2010, original source:
http://www.drillspot.com/products/51570/Hoffman_1A_Adjustable_Automatic_Air_Vent_For_Steam_Radiators
Hoffman can be contacted at bellgossett.com/hoffman-specialty-products/ - Hoffman CONVECTOR STEAM VENTS [PDF] Hoffman Specialty, ITT, web search 12/28/2010, original source:
http://www.hoffmanspecialty.com/pdf/hs900/HS900-conv109.pdf - Hoffman, Special Steam Vents, Hoffman Specialty heating products, web search 12/27/2010, original source:
http://www.hoffmanspecialty.com/pdf/hs900/HS900-3474.pdf - Hoffman Steam and Water Vents, Selection Guidelines - found
in HOFFMAN SPECIALTY CATALOG HS-900G [PDF] - Steam Vents Hoffman Specialty, web search 12/27/2010, original source:
Hoffman can be contacted at bellgossett.com/hoffman-specialty-products/ - Hoffman SPECIALTY SERVICE PARTS CATALOG [PDF] Op. Cit. repair parts and service
- Holohan, D, "Care & Feeding of Air Vents", Dan Holohan, Old House Journal Online, November 2004
- Sid Harvey AIR VENT STEAM VENT CATALOG [PDF] Sid Harvey Industries, Inc
605 Locust Street
Garden City, New York 11530 USA, Tel: (516) 745-9200 Email: sales@sidharvey.com
Brief description of Amtrol Air Purger, Hoffman NO. 40 radiator steam vents and Eaton (Dole) 1-pipe steam system vents. This page includes detailed recommendations among Eaton steam radiator vents for models depending on distance of the radiator from the boiler or from the thermostat. Retrieved 2020/02/28 original source: http://orders.sidharvey.com/IMAGES/catalog/Unpriced/20104-34.pdf - Spirax Sarco Corporation USA, 1150 Northpoint Blvd.
Blythewood, SC 29016
USA
Contact Details
Tel: (800) 575-0394
Fax: (803) 714-2222
Email: InsideSalesLeads@Spirax.com
Website http://www.SpiraxSarco.com/us/ - Vent-Rite Valve Corporation:
1875 Dewey Ave. Benton Harbor, MI 49022 TEL: (269) 925-8818
Emerson Swan, Inc. 300 Pond Street Randolph, MA 02368 Tel: (781) 986-2000 Fax: (781) 986-2028 info@emersonswan.com
Vent-Rite #1 with the Vent-Rite #35 Steam Heat Main air valve. The Vent-Rite #1 (or #11) is designed for 1-pipe steam systems and mounts on the radiator.
The Vent-Rite #35,75, or 77 are intended for main vents (two pipe systems and located on the mains); The Vent-Rite #31 & 33 are used on steam risers and on steam convectors. Contact the company for help or to download their product guide.
...
Reader Comments, Questions & Answers About The Article Above
Below you will find questions and answers previously posted on this page at its page bottom reader comment box.
Reader Q&A - also see RECOMMENDED ARTICLES & FAQs
On 2014-10-02 by Adriann - where to buy equivalent/replacement for Dole steam vent valves, sizes 3, 2B and 1A
We are new owners of a 1930's home with 1-pipe steam radiators (been doing my research....) I have Dole valves, sizes 3, 2B and 1A and cannot figure out the equivalent sizes for any other brand.
I have to replace 13 of these 'steam whistles' and would appreciate help in figuring out what size I need, have not had any luck with big box stores as they look at the steam valves with bemusement when I show it to them,
Thanks for any help
On 2014-10-06 by (mod) -
Adriann
You'll be much happier if you give up on the big box stores and stop by a local plumbing and heating supplier, asking for help from their steam expert. At least the larger suppliers usually have someone at hand who knows steam controls and can help you specify the replacement steam vents you need.
Dole made air vents and steam vents: the Dole steam vent was sold in several models, such as the Dole Vari-Vent Air Valve No. 1A, but your sizes 2B and 3 are higher capacity.
Also check our table in the article above where we give Replacement Steam Vent Substitution Sizes for Dole Steam Vents
To remove and replace a steam vent the heat must be off and the radiator cooled to avoid risk of burns. I would NOT remove a vent before locating a local steam vent supplier as I wouldn't want to risk having to leave the house with no heat for a time.But you don't need to replace with the same brand, just the same type and same threaded tapping size.
On 2014-10-14 by Adriann
Thank you very much for your response, Dan. I will try a plumbing/heater store.
...
Continue reading at STEAM VENT TYPES, SELECTION where we describe just about every type of automatic steam vent used on residential and most commercial systems. or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see these
Recommended Articles
- STEAM HEAT RADIATOR REPAIR
- RADIATOR VALVES & HEAT CONTROLS
- STEAM TRAPS
- STEAM VENTS - home
- UNEVEN or INSUFFICIENT HEAT DIAGNOSIS
Suggested citation for this web page
STEAM VENT TABLE & CROSS REFERENCES at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
Or see this
INDEX to RELATED ARTICLES: ARTICLE INDEX to STEAM BOILERS
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Citations & References
In addition to any citations in the article above, a full list is available on request.
- Honeywell Corporation, Tel: U.S. 1 (877) 841-2840, International 001 (480) 353-3020, Website: www.honeywell.com
- Vent-Rite Valve Corporation: 1875 Dewey Ave. Benton Harbor, MI 49022 TEL: (269) 925-8818 FAX: (269) 925-7888
- Emerson Swan, Inc. 300 Pond Street Randolph, MA 02368 Tel: (781) 986-2000 Fax: (781) 986-2028 info@emersonswan.com
- Barnes & Jones Corporation, 91 Pacella Park Drive Randolph, MA 02368, Tel: 781-963-8000calibrated steam traps and vents, Email: bnesbitt@barnesandjones.com. Vent-Rite steam vents for radiator control.
- Gorton Heating Corporation, 546 South Avenue East, Cranford, New Jersey 07016, Tel: 908-276-1323, email: info@gorton-valves.com, fast venting valves for steam heating systems.
- "Rv-4 One-Pipe Steam Radiator Valve", available from Armstrong International,
816 Maple Street, Three Rivers, MI 49093 USA, Tel: (269) 273-1415, Armstrong has offices in Beijing, China, Belgium, India and Mexico. Web search 12/27/2010, original source:
http://www.armstronginternational.com/thermostatic-valves-rv-4-one-pipe. - "Special Steam Vents", Hoffman Specialty heating products, web search 12/27/2010, original source:
http://www.hoffmanspecialty.com/pdf/hs900/HS900-3474.pdf - "Steam and Water Vents, Selection Guidelines - Steam Vents", Hoffman Specialty, web search 12/27/2010, original source:
http://www.hoffmanspecialty.com/pdf/hs900/HS900-stvents.pdf - Hoffman 1A adjustable steam vents, available from Hoffman Specialty, ITT, web search 12/27/2010, original source:
http://www.drillspot.com/products/51570/Hoffman_1A_Adjustable_Automatic_Air_Vent_For_Steam_Radiators - Hoffman Convector Steam Vents, available from Hoffman Specialty, ITT, web search 12/28/2010, original source:
http://www.hoffmanspecialty.com/pdf/hs900/HS900-conv109.pdf - Report 95-14, PB96-198163 Thermostatic Radiator Valve (TRV) Demonstration Project, contact NYSERDA. 17 Columbia Circle, Albany, NY 12203-6399 Toll-Free: 1-866-NYSERDA, Tel:(518)465-6252, Ext. 241. Web Search 12/27/2010, original source: http://www.homeenergy.org/archive/hem.dis.anl.gov/eehem/96/960509.html
- VariValve® Quick-Vent from Heat Timer, adjustable radiator and main line vent valves for one pipe steam systems, web search 12/27/2010, original source: http://www.heat-timer.com/enFiles/ProductDocument/literature/VariV056082C.pdf
- "Care & Feeding of Air Vents", Dan Holohan, Old House Journal Online, November 2004
- The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update, (see next item in this list). ITT Fluid Technology,
1133 Westchester Avenue
White Plains, NY 10604, tel +1 914 304 1700 fax +1 914 696 2950 www.ittfluidbusiness.com - The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
- Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
- "Residential Steam Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
- The Heat Efficiency of Steam Boilers, Bryan Donkin
- Steam Boiler Operation, Principles & Practice, James J. Jackson
- The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
- The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
- Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
- "Residential Steam Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
- Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
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- In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
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