4A, 1/2" x 3/4" Straight Steam Main Air Valve Zoom

4A, 1/2" x 3/4" Straight Steam Main Air Valve

SKU:401413

Brand: Hoffman

Hoffman
Qty Price
$31.45
/ each
$180.90 / box (6 units x $30.15)
In Stock! Ships in 24-48 Hours
(136 Available)
0

Resources

Specs

Application: Main Vent
Size: 1/2" x 3/4"
Type: Non-Vacuum
Float-type Vent
System Type: Steam
Max Pressure: 10 psig
Max Operating Pressure: 2 psig
Mount: Straight
Adjustability: Non-Adjustable
Material: Steel
Thread Type: Female
Male
Temperature Range (F): 140°-240°F
Max Temp (F): 240°F
Min Temp (F): 140°F
Thread Size: 3/4"
1/2"

Description for Hoffman 401413

Air Valve (non-vacuum)

  • Float-type thermostatic vent
  • For residential or small one-pipe or two-pipe systems
  • Single non-adjustable port
  • 1⁄2" NPT female and 3⁄4" NPT male straight shank
  • Install 6-10" (150-250mm) above horizontal return and 18" (450mm) above the boiler water line
  • Maximum operating pressure 2 psig (0.13 bar)(Drop away pressure - maximum pressure against which the vent can open).
  • Maximum pressure 10 psig (0.7 bar)

4A, 1/2" x 3/4" Straight Steam Main Air Valve

REVIEW SNAPSHOT®

by PowerReviews
Hoffman4A, 1/2" x 3/4" Straight Steam Main Air Valve
 
4.8

(based on 5 reviews)

Ratings Distribution

  • 5 Stars

     

    (4)

  • 4 Stars

     

    (1)

  • 3 Stars

     

    (0)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

100%

of respondents would recommend this to a friend.

Pros

    Cons

      Best Uses

          • Primary use:
          • Personal (4)

        Reviewed by 5 customers

        Sort by

        Displaying reviews 1-5

        Back to top

         
        5.0

        Definately would buy this product again

        By anna the janitor

        from pennsylvaniaa

        Verified Buyer

        Pros

          Cons

            Best Uses

              Comments about 4A, 1/2" x 3/4" Straight Steam Main Air Valve:

              Ordered this product before and again it got the job done right the first time.

              • Primary use:
              • Business
               
              5.0

              Hoffman Main AIr

              By Oryonx

              from Westchester, NY

              Verified Buyer

              Pros

                Cons

                  Best Uses

                    Comments about 4A, 1/2" x 3/4" Straight Steam Main Air Valve:

                    I installed this vent on my main steam line and I immediately see a difference by how fast the radiators now heat up. It is definately worth it to install this valve it will pay for itself during the course of the heating season 2 times over.

                    • Primary use:
                    • Personal
                     
                    5.0

                    Quality Product

                    By Oryonx

                    from New york, NY

                    Verified Buyer

                    Pros

                      Cons

                        Best Uses

                          Comments about 4A, 1/2" x 3/4" Straight Steam Main Air Valve:

                          I used this product to replace my main vent on a one pipe steam heating system. The house now warms up a lot faster. Just make sure you have it mounted on a 6-inch or higher nipple which will help keep it from getting clogged with stuff from the piping.

                          • Primary use:
                          • Personal
                           
                          5.0

                          Great Product

                          By DJ

                          from New York

                          Verified Buyer

                          Pros

                            Cons

                              Best Uses

                                Comments about 4A, 1/2" x 3/4" Straight Steam Main Air Valve:

                                Needed to replace a leaking main vent on single pipe system. Worth the extra money to get a quality product. Now my systems vents quickly, heats evenly and is quiet. Glad I purchased it!

                                • Primary use:
                                • Personal
                                 
                                4.0

                                You get what you pay for.

                                By Bob C

                                from Boston, Ma

                                Verified Buyer

                                Pros

                                  Cons

                                    Best Uses

                                      Comments about 4A, 1/2" x 3/4" Straight Steam Main Air Valve:

                                      I bought these to replace some air valves that I bought at [...] valves were cheaper but they don't last. Pay a little more - get a lot more.

                                      • Primary use:
                                      • Personal

                                      Displaying reviews 1-5

                                      Back to top

                                      Q&A: Ask the Questions, share answers

                                      Do you have questions about this product?

                                      get answers from real customers and in-house experts with AnswerBox.

                                      1 Question | 5 Answers
                                      Displaying question 1
                                      • 4A, 1/2" x 3/4" Straight Steam Main Air Valve

                                        Q:

                                        I have to replace a steam main air valve in a one pipe system that is at least 50 years old. The markings on the valve say its a Vintor No 45 made by Hoffman Speciality Company of Indianapolis, Indiana. Will this 4A valve work?
                                        Asked on 10/1/2013 by Jim

                                        5 answers

                                        • VERIFIED BUYER

                                          A:

                                          Jim:
                                          A couple of years ago I was in the same position - though not with the
                                          same existing valve that you had. I replaced my main valves with 4A's
                                          (there were three) and things have been humming ever since.
                                          I have an old, old one pipe system and the valves when we bought the
                                          place were at least 30 years old.
                                          I'd give it a shot and expect the best...worked for me.
                                          Good luck,
                                          Josh

                                          Answered on 10/2/2013 by Anonymous
                                        • VERIFIED BUYER

                                          A:

                                          I had the same valve on my one pipe system. I bought this 4A valve and it works just fine. Been on for several years now without any problem. My system is quite old, house built in the 1920's. Only place I could find this and the valves for my radiators was here at Pex Supply.

                                          Answered on 10/1/2013 by Anonymous
                                        • VERIFIED BUYER

                                          A:

                                          I used this valve successfully in my residential 2 zone single pipe system as the main vent for each zone.  I don't know what kind of vents we replaced because the markings had long disappeared.  The important thing is what pressure you want the valve to close at.  My system operates between 1 1/2 and 2 psi so I needed this vent because it closes at 2 psi.  When the boiler comes on and begins to create steam the main vents are open allowing the steam to push the air out of the system and quickly fill the system with steam.  The vents are at the very end of the line so when the steam pressure gets to 2 psi (at the main vents) they close (and at this point all the air is out of the system) and the steam begins to travel to the individual radiators.  Without the correct main vent you can end up having steam get to the radiators unevenly or have a very slow startup because all of the air hasn't been evacuated from the system.  Pick the correct main
                                          valve according to your system's operating pressure (most residential single pipe systems operate at less than 2 psi) and then change the fittings if necessary if the new valve won't screw in where the old one was.  Then fire up the boiler cold and listen for air to begin escaping from the main vent while checking the pressure.  Air should begin escaping within a few minutes and then the vent should close when the pressure reaches 2 psi.  Hope this helps.
                                          ps.  most problems with vintage residential steam systems come from somebody setting the pressure too high.

                                          Answered on 10/2/2013 by Anonymous
                                        • VERIFIED BUYER

                                          A:

                                          If the operating pressure is under 2 psi you can use the 4A if the operating pressure is above 2 psi (and under 6 psi) you can use the 45.
                                          From mobile device

                                          Answered on 10/1/2013 by Anonymous
                                        • VERIFIED BUYER

                                          A:

                                          Looks like there is a slight difference between the 4A and the 45. The maximum operating pressure is different (2 psi vs 6 psi). The max pressure is the same for both (10 psi). All else appears to be the same. On the main, this should not be a problem.
                                          The purpose of the vent on the main is to bleed the air out of the system on startup to get the steam to the radiators quicker. A main air valve functioning properly will save fuel and get the house warm quicker.

                                          Answered on 10/1/2013 by Anonymous
                                      Displaying question 1

                                      Do you have a question about this product?