Taco 400-4 1/8-Inch-NPT Float Air Hy-Vent

exact replacement - works fine

Between a faulty auto-fill valve and air vent, my second floor radiators would become air-locked. Replaced both and now Im staying nice and warm! This is one of those preventative maintenance items you should replace every couple/few years.

Installed easy and works as it is supposed to.

1/4

Used Taco products before and are first quality. Valve was delivered with bent bleeder tab but that was from handling and delivery. Repaired it myself and all good. Needs to be shipped in a box and not a plastic bag AMAZON!

Works great. Was very easy to install. I recommend this product. I might Buy an extra one to have in case I need it but this one seems very solid.

I installed this at the junction point of the feed manifold from my boiler to all the zones in my house, a direct replacement of a failed automatic bleed valve. This Taco 400-4 works like a charm. Upon refilling of the system, it immediately started hissing, which is good. Overall it took about 20 minutes to purge all the air out of the system. Very impressed. The material, construction and heft of this Taco 400-4 is quite good.

Perfect replacement the old one that was bad.

Feb 2017 update: Its 2017, but I noticed that I havent had a leaking Hy-Vent since I installed a heat pump hot water heater in 2015. This means the hydronic system never fires up to provide domestic hot water during the non-heating seasons. Whereas the oil furnace used to run daily to make hot water for laundry/showers/dishes, now it only runs September to April/May for baseboard heating. I should expect the Hy-Vents to double their service life from 3 years to 6 years. Original review: I would have given it 3.5 stars if possible. It does a great job of purging air from my hydronic/baseboard heating system zones. However, I have been marking dates on them since we remodeled our house 4 years ago, and none of them are older than 3 years. The culprit is always leaking water from the top cap, and I always find that the o-ring has been deformed permanently from just 2-3 years of use (see photos of failed vent valves that Im replacing with new ones I just purchased from Amazon). I would have given it 5 stars if Taco would sell a 3-pack or 5-pack of o-rings for say $2 so I dont have to toss an entire vent when only the o-ring fails. I expect these new ones to not last past 2017. Replacing these vents at the zones is fairly straightforward with only minor water spills and leaks to collect since I have a pair of shutoff valves at each zone. The one on top of the expansion tank is the most challenging since a lot of water comes out of the tank; Im going to use another reviewers advice and install a shutoff valve the next time the expansion tank vent fails.

Very high quality, heavy duty boiler vent. Simple install and performed much, much better than others I have tried in the past. There was a short period of air expelled quickly and then within 10 minutes all the sputtering stopped and all the air was expelled from the system. It seems that the other valve-type boiler vents would only last a couple of months before clogging and leaking again. This vent works under a somewhat different principle, using a float inside a closed chamber. I suspect this should last through this season and from my research it should also last for quite a few years. Keeping my fingers crossed.