Apply to be a TradeMaster!
Main product image of 75, 1/2" x 3/4" Straight Steam Main Air Valve
Magnifying glass
Hover image to zoom

75, 1/2" x 3/4" Straight Steam Main Air Valve

Brand:
Hoffman
SKU:
401434
Rating:
(19)
Q&A:
(2)
75, 1/2" x 3/4" Straight Steam Main Air Valve
Magnifying glass
Hover image to zoom
$161.00 each
In Stock
In Stock
Get 115 Wed, Jul 30
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days

Product Highlights

Product Highlight: Size
1/2" x 3/4"
Product Highlight: System Type
Steam
Product Highlight: Max Temp (F)
240°F Max Temp
Product Highlight: Max Pressure
15 psig
Product Highlight: Mount
Straight
Product Highlight: Material
Steel

Description

Air Valve (non-vacuum)
  • Float-type thermostatic vent
  • For medium and large systems
  • Single non-adjustable port
  • 1⁄2" NPT female and 3⁄4" NPT male straight shank
  • Maximum operating pressure: 3 psig (0.2 bar)(Drop away pressure - maximum pressure against which the vent can open).
  • Maximum pressure 15 psig (1.0 bar)

Specs

Application:

Main Vent

Size:

1/2" x 3/4"

Type:

Non-Vacuum

Float-type Vent

System Type:

Steam

Max Pressure:

15 psig

Max Operating Pressure:

3 psig

Mount:

Straight

Adjustability:

Non-Adjustable

Material:

Steel

Body Pattern:

Straight

Thread Type:

Female

Male

Max Temp (F):

240°F

Temperature Range (F):

140°F - 240°F

Min Temp (F):

140°F

Thread Size:

3/4"

1/2"

Contact

+
Help Face

Questions?

Customer Support has a delayed opening today for a monthly team meeting to better support you.
Call or text 888-757-4774
Special Hours
9:15am7:45pm
MondayThursday
8am7:45pm
Friday
9am7:45pm
SaturdaySunday
9am5:45pm

Response by Tue

You May Also Need

Product Reviews

4.89 out of 19 reviews
100% would recommend this product
4.89
out of 19 Reviews
100% would recommend this product
WRITE A REVIEW
5 star
95%
4 star
0%
3 star
5%
2 star
0%
1 star
0%
WRITE A REVIEW

Most Liked Positive Review

great air valve ; i have bought 4

ive been using these for a year now , as a recommendation , from the lost art of steam ! they work great , if installed properly , i have just finished my second steam boiler in a year , i use the burnam mega steam , & these are are a great companion , as the lost art says , u will find the main vent capped off , or someone has installed the wrong 1. i am also repiping an existing steam boiler that the was totaly piped wrong less than 6 yrs ago , & the #75 will b there too
VS

Most Liked Negative Review

Brings heat fast

However, The previous Hoffman 75 didn't even last for a year.
Showing 1-10 of 19 reviews

Works great. Just hope it lasts.

This part now costs 2.5 times what it cost 8 years ago. Crazy.
Richard
New York
7 months ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Brings heat fast

However, The previous Hoffman 75 didn't even last for a year.
Ned
Bx NY
2 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Very nice

It cost more, but my steam system deserves it. Hah! Just kidding, but it is really nice. Big, but I wanted something that will vent air quickly and I think this is the one.
Oskie
Massachuestts
3 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

I would buy this again if needed.

Had our 45 year old Steam Boiler replaced and decided it would be worth replacing this as well.
Mr. H
Michigan
3 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Expensive but worth it.

I proactively replace these every two years or so. They are expensive, probably due to the solid copper construction. I need peace of mind that my main steam vents are not going to blow out and these provide it. Cheaper vents will blow out . It happened to me in the past with other cheap vents and ruined my dining room hardwood floor.
Mutrock
Easton, CT
4 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

I would buy this product again

As advertised, quick shipping!
CB
North Carolina
4 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

I wouldn't buy these again

Air bleed on steam system to help in faster start up and reduce hammering.
HVAC Tech
Birmingham, AL
5 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

I would buy again.

Works as described
Mike
IL
6 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Yes would buy again

Great vent for larger steam systems. Does the job
David
Lynchburg, VA
7 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Good product.

We get 10 years out of them
Bob - Condo Board
St. Paul MN
7 years ago
Verified Buyer Icon
Verified Buyer
Was this review helpful to you?

Product Q&A

2 Questions
2 Questions
ASK A QUESTION

Q: How tall is this unit

Asked by Joseph 12 years ago

Add your answer

* Required Field
-

Good AM The Hoffman model 75, p/n 401434, is 5-5/8" tall overall. Michael Milawski Associate Director of Physical Plant SUNY Downstate Medical Center

Was this review helpful to you?

Q: What is it's puprose? How often must it be changed

Asked by 15 years ago

Add your answer

* Required Field
Verified Author and ReplyVerified Reply- PexSupply Staff

Air Valves perform two important functions in a piping system. They maintain system design efficiency and provide system protection. Air valves do not need to be changed as long as they are functioning properly.

Was this review helpful to you?
- Jake

This valve vents cool air from the radiator system to help the steam circulate. When the air heats up, the valve closes so no steam leaks out. These valves last for years, but eventually stop working. I have heard that they last 10 to 15 years, but do not know. When they stop working, they will remain open all the time, and will leak steam into the house throughout the whole steam cycle.

Was this review helpful to you?
- John in Building Maintenance

This vent removes steam and hot air pockets from the condensate return lines in a closed loop steam heat system. That is, steam goes out to your radiators to heat your building. As the steam gives up its heat to warm your room, the steam condenses into hot water, which returns to the boiler to be re-heated. For various reasons, steam may sometimes also return with the hot water, as well as air bubbles. These pockets can block the flow with pressure, cause your boiler to be full of air, or damage your pipes. This vent lets the steam and hot air out, but keeps the hot water in. If properly placed and sized, this vent should last for decades.

Was this review helpful to you?
Free Shipping
On orders over $99
We offer flexible shipping and scheduling options, up-to-date delivery estimates, and free ground shipping on any order over $99 to make sure your order gets to you on-time, for less.
Shipping Policy
Easy Returns
Returning items is as simple as 1-2-3
Ordered the wrong product? Item damaged in transit? Our 3-step process makes returning products easy – even up to a year after purchase – with no restocking fees on returns made within 90 days.
Return Policy