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Hoffman 70A

delcrossv
Member Posts: 2,158
How does the 70A compare to the 40- faster, slower? (not listed in the guide to vents)
It's twice the price, so I'd like some guidance before I get some.
Thanks!
It's twice the price, so I'd like some guidance before I get some.
Thanks!
Trying to squeeze the best out of a Weil-McLain JB-5 running a 1912 1 pipe system.
0
Comments
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Slightly slower. ISTR it's more expensive because it is built to military specs.All Steamed Up, Inc.
Towson, MD, USA
Steam, Vapor & Hot-Water Heating Specialists
Oil & Gas Burner Service
Consulting1 -
The difference between the #40 and 70a valve is the operating pressure.
The 70a is good to 15 psi max and the 40 is good to to 10 psi max.
In a normal operating system in lower pressure applications such as systems that operate at pressures under 5 psig I would certainly use the #40 vent valve. There is no difference in the air discharge rate that would be meaningful.
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