Main Vent Brand

Frankfog2

I’m heading to the hardware store later today to get a new main vent for my system. I have one vent at the end of the main near the last radiator that goes to the second floor. What is preferred. Maid O Mist or Hoffmans? Replacing them because the radiators tend to spit and hiss a little. I have maid o mists on the radiators. The main had a dimension of 2 inches. Not sure about the length, it’s relatively short though. 

dabrakeman

Gorton #1 or #2 are perhaps the most popular choices for main venting. Order them online i.e. through Supplyhouse.com. A #2 has 3x the venting of a #1.https://supplyhouse.com/Gorton-Air-Valves-302000

Frankfog2

dabrakeman said:

Gorton #1 or #2 are perhaps the most popular choices for main venting. Order them online i.e. through Supplyhouse.com. A #2 has 3x the venting of a #1.https://supplyhouse.com/Gorton-Air-Valves-302000

I already have the Vent off and i brought it with me so i can pick it up after work. It’s supposed to be cold tonight so for sure can’t wait for the delivery. My hardware store only has Maid o Mist and Hoffmans. Which do you think would be better? I’ll order the Gortons and replace them during the summer then. 

dabrakeman

Hoffman 75 is a good vent but really expensive particularly for the amount of venting you are getting. If I were you I would save my money and pick up the Maid-O-Mist today with the plan of ordering a good Gorton later on. You could even put the two together on an antler next summer.

dabrakeman

Steamhead

@Frankfog2 , Maid-o-Mist used to have a #1 main vent but I don't see it on their site now. But you could get a #D vertical type which has the same capacity- see:

https://www.maidmist.com/jacobus-steam-vents/model-d/

If your old vent has 3/4" threads, you'd need a 3/4"x1/4" or 3/4"x1/8" bushing to make the vent fit.

Frankfog2

Steamhead said:

@Frankfog2 , Maid-o-Mist used to have a #1 main vent but I don't see it on their site now. But you could get a #D vertical type which has the same capacity- see: https://www.maidmist.com/jacobus-steam-vents/model-d/ If your old vent has 3/4" threads, you'd need a 3/4"x1/4" or 3/4"x1/8" bushing to make the vent fit.

Hm. why would i need a bushing, i thought it was a simple on and off

dabrakeman

Just match the thread size for what you bring in with what you buy. If they differ, you will need a bushing.

ethicalpaul

If your hardware store has this one, it's very good. Really you can turn any MoM into a #1 main vent by just removing the threaded orifice off the top.

https://www.supplyhouse.com/Jacobus-Maid-O-Mist-J1-1-3-4-x-1-2-Main-Vent-Valve-3563000-p

Frankfog2

ethicalpaul said:

If your hardware store has this one, it's very good. Really you can turn any MoM into a #1 main vent by just removing the threaded orifice off the top. https://www.supplyhouse.com/Jacobus-Maid-O-Mist-J1-1-3-4-x-1-2-Main-Vent-Valve-3563000-p

That’s the one i was looking at, so i don’t have to make a new thread. is this a good setting for my pressuretrol? i’m not sure if you’ve seen my other threads but this thing was set up with the main at like 5 and the diff just below it. I read some of the steam books by hollahan? (i don’t remember the name) i adjusted it. is this better

Jamie Hall

Yes. And that is an excellent pressuretrol. Keep it. Just make sure it's level.

Mad Dog_2

Gorton or Hoffman..thats it...all the rest....ehhh..Mad Dog 🐕 

Steamhead

Wonder why the #1 was not on M-o-M's site?

ethicalpaul

Isn't it?

https://www.maidmist.com/jacobus-steam-vents/model-1/

Steamhead

ethicalpaul said:

Isn't it?

https://www.maidmist.com/jacobus-steam-vents/model-1/

Didn't come up last night.

Mad Dog_2

Hoffman or Gorton...that's the best of choices...Mad Dog 🐕 

STEAM DOCTOR

Put in a plug in the meantime. Nothing dreadful will happen over the next day or two. Order the proper vent from supply house

Mad Dog_2

Agreed.  No biggie..Mad Dog 🐕 

SteamingatMohawk

I have been AWOL for many months and just found a situation that can benefit from HH opinions.

Two mains, single pipe steam heat. Main vents at the boiler end of the returns are Gorton#1s, been there for at least 4 years. This morning I found one to not be venting, so I tried to source a direct replacement locally. Big boxes don't carry Gorton (I don't trust knockoffs anyhow).

I went to 4 credible local plumbing suppliers. 3 don't carry Gorton, but do carry Vent Rite #35s. The 4th does carry Gorton #1, but is out of stock until 50 are delivered on Wednesday.

Also, I had 2 Vent Rite #35s on hand, but didn't remember when I bought them.

So, since the Gorton's are not as readily available, I am trying to decide if the Vent Rite #35s are a preferred choice and why.

Looking at the Gill - Pajek report the Gorton capacity is 3X the Vent Rite. I am disappointed in the apparent fact that the Gorton didn't vent and wonder if the Vent Rite is a better long term choice. I intend to use the same type valve on both returns.

So, what is the perspective of HHers, stick with the Gorton #1 at the higher venting capacity or go with the more locally available Vent Rite #1?

This is for a rental property and reliability, quality, etc. are more important than cost.

Have at it folks.

Steamhead

How long are the steam mains, and what pipe size?

SteamingatMohawk

I should have mentioned the size. Front main is 23 ft of 2 inch, rear main is 11 ft to the last riser in each main. The returns back to the Hartford loop are about the same.

Several years ago when I was an early novice in steam heat, I installed a Gorton#2 after the last riser on the front main. Also, I had to make a mod where the returns were piped to come together above the water line to connect below the waterline, which solved a lot of my balancing difficulties between the front and back returns. I keep the Gorton #2 on line because it doesn't seem to hurt anything and I had already spent the time and money to install it.

The system has been running excellently since I did the mod and I finally was able to balance the system.

As the shoulder season came upon us this year, the system was acting up a bit. Today I found what could have been contributing to the unbalance (admitting, of course, that the shoulder seasons can be a distraction).

Boiler is 135K or so.

For anyone interested, one other thing I did because I don't live at the house is to install a battery powered wireless thermostat with a gateway so I can monitor and control the system from my cell phone. That $300 cost is a tremendous asset for the remote capability and the fact I can put the thermostat anywhere in the house without having to run wires. Based on what I learned over the years, I put it in the coldest room in the house and it was easy to balance the rest of the rooms. With no zones, it made life and tenants happy.

SteamingatMohawk

Front is about 1/2 a cubic foot and the rear is 1/4 cubic ft by my calculations.

Steamhead

You could try teeing both Vent-Rites on the rear main and see how that works.

dabrakeman

If you have a Gorton #2 after the last riser on the front main then why bother with another vent at all at the end of the return on that main? You could even plug it and use the working Gorton #1 on the rear main. I personally don't think a Ventrite 35 is large enough for any main.

There were other discussions on the topic but it makes more sense to me to have the vents at the ends of the mains after the last riser if that location is at all accessible. Putting them at the ends of the main extension back at the boiler works of course and is done quite often (likely for accessibility) but it is just a little more pipe that steam needs to push air out of before the steam wants to start going to the radiators. I have measured the time difference on my own system.

SteamingatMohawk

I agree with all that you say.

That being said, having the both available for venting does provide some additional venting capacity, so that's pretty much why I left them both on line. That raises the question about if the #2 at the end of the supply portion is in service and the #1 at the end of the line is not, what happens to the air in that 23 foot long return? I am not smart enough to figure that out.

There have been many "frettings" about oxygen in the makeup water causing corrosion, when in fact it is driven off the first time the water boils. If the return section is not effectively vented through the #2 with the #1 shut, whatever gas is in the pipe will contact condensate. To what extent that makes any difference, I have no idea. How much can half a cubic foot of air affect corrosion. That's beyond my level of understanding.

Besides, when the system cools down air is sucked back in anyhow, so it probably makes next to no difference at all. Maybe that just means less air is sucked back in because of the residual that wasn't vented. Beats me!

I don't think I have enough headroom to move the Gorton#2 to replace the Gorton #1 at the end of the return. I'll take a look and if I can fit it, I may try just for the heck of it. It's no big deal to swap and I have isolation valves at those locations, so no extra plumbing is needed to do it.

I hope this isn't causing headaches, but I find the "magic" of steam heat to stimulate my imagination.



Has anyone else ever thought about these things?

dabrakeman

SteamingatMohawk said:

I agree with all that you say.

That being said, having the both available for venting does provide some additional venting capacity, so that's pretty much why I left them both on line. That raises the question about if the #2 at the end of the supply portion is in service and the #1 at the end of the line is not, what happens to the air in that 23 foot long return?

As steam advances and closes the vent at the end of the main theoretically the steam should stop advancing through that 23ft return since that return drops down below water level back at the boiler. Can you find any other path by which air can be pushed through that pipe and out to atmosphere if the vent at the end of the return is stuck closed?

AdmiralYoda

Are we not recommending Barnes and Jones Big Mouth's as main vents anymore? Similar price as a Gorton #2 and probably more venting capacity. Usually a little smaller too.

SteamingatMohawk

@dabrakeman I assume "vent at the end of the main" refers to the Gorton#2 after the last riser. That being the case, we are saying the same thing, the air between the G#2 and the water line is trapped. I just got off the phone with Ken at Gorton and he agrees that if the G#1 at the end of the return was shut or removed the air would be trapped. I called him for a different reason....see below.

I've talked to him in the past and he has been very helpful.

I tried to locally source a replacement Gorton. The big box stores don't stock them, but you guys know that. FW Webb is out of stock and twice the price. Grainger doesn't carry it.

I went to 4 local reputable plumbing houses and none sells Gorton specifically. One house said they do and had some on order, so I went to pick one up when they were in stock only to find they actually sell the Jacobus/Maid o Mist #1. I wanted Gorton. The salesman said he thought Gorton and Jacobus/Maid o Mist had become one company...I doubted that and decided to check it out. Bottom line, he was wrong when I asked Ken at Gorton. I'm not sure if the local guy was honestly mistaken or blowing smoke at me.

In any event, I gave up trying to get it locally and ordered from Supply House and will have it today.

Success was stolen from the jaws of defeat one more time!

@AdmiralYoda In the few years I have been HHing, I have not used Big Mouths, so I have no opinion. Smaller in size is a benefit in tight arrangements, so that's good to keep in mind.

Steamhead

The drawback of the Big Mouth is it does not have a float that closes against water. But they make great crossover traps.

ethicalpaul

I don't like the Big Mouth, but not closing against water is not why. I would much rather have the main vent dump water in my basement, than have one or more radiator vents dumping water in my living space.

But really, why would a main vent have to close against water?

Steamhead

ethicalpaul said:

I don't like the Big Mouth, but not closing against water is not why. I would much rather have the main vent dump water in my basement, than have one or more radiator vents dumping water in my living space.

But really, why would a main vent have to close against water?

Because some folks don't want them dumping water in the basement.

ethicalpaul

But I mean how would water get up there? Something would have to be very very wrong

STEAM DOCTOR

Never had a water issue with BM. But had many that leaked steam. Some out of the box and some months later. From all the various "generations" of the big mouth. I was once, one of the BM's biggest fans. Not anymore. Way too many callbacks and headaches. 

SteamingatMohawk

Overfilling could get enough water in the system. Once upon a time I had a tenant call me that water was coming out of the valve in a first floor bathroom. The radiator had been removed years ago to provide more space in the room. I don't recall if I didn't shut the fill bypass all the way or the auto feeder leaked the water.

I obviously drained the system and capped the valve outlet.

gfrbrookline

I have 15 Big Mouths in my three building, they had some QC issues early on but they have been reliable for me over the past five years.

AdmiralYoda

My Big Mouth is going on 5 years old and is still working like a champ. But based on these comments I'm going to watch it during a few heating cycles to make sure it isn't leaking any steam. I don't need to add much make up water so I doubt it is.

I am about to install another vent on my other main that is currently blocked off. makes me wonder if I should go Big Mouth or Gorton #2.

gfrbrookline

@AdmiralYoda go with the big mouth, if it fails return it and replace it with G2'S. It would be a nice QC check on the newer BM's.

Neild5

Of the 9 BM, I have had 3 leak steam.  I replaced the original o-ring that looked melted with hi temp silicone.   No problems after that.