Main Venting/Gorton radiator balancing

gfrbrookline

So after recommending Ventrite No 1's for a long time and at times Gorton's, I tried a Hoffman 1A today, set to 3.5. Does anyone else find them to sound like a asthma patient when they are venting? Much more venting noise than a Gorton but similar sound. I find the Ventrite virtually silent.

My vaporstat is set 10oz. cut out and 4oz. cut in so it's not a pressure issue.

BobC

I gave up on the Hoffmans years ago, the noise was a minor irritant but the waterlogging was just a killer. My system was running at 12 oz and 4oz.

Early this morning I woke up and was trying to decide if I should get up. The steam boileer was firing and I could just barely hear my Maid o Mist vent that is about 9 ft away from me in the quiet - much quieter than the Hoffman that preceded it.

Bob

acwagner

When I used 1A's I don't recall them being especially noisy during the venting period. They do click and hiss after steam hits them, though.

Although, for a brief period I operated in the pressure range you are and all my vents made more noise while venting. That's the reason I switched to venting my rads quickly and my main really quickly--no back pressure while the vents are open.

gfrbrookline

Thanks,

@acwagner , my mains have six Big Mouths and four Gorton 2's on them so I don't think I am lacking venting on the mains. What are you using on your rads? At one point I had Gortons 6's, C's and D's on the furthest radiators and they heated on the sides and top but the middle was cool, six and eight fin rococo radiators waist high.

acwagner

I have mostly 6's, C's, and D's, with one 4, one 5, and two "5.5's" that I made by modifying a Gorton 5. My rads fill from the top down. When it recovers from setback the whole rad is hot, so I don't think I'm having any problems with short circuiting in the radiator. My rads are 38" tall Corto's. Most are around 30 EDR.

My theory is the ratio between total radiator venting to main venting is a part of it. The sum of my main venting is almost 5 times larger than the sum of all my radiator venting. I also purposefully run my system so that a normal call for heat doesn't have steam hit any of rad vents.

I know you have a large apartment complex, so perhaps my theory doesn't scale up well. Also makes it harder to experiment.

I am curious what your ratio between main and rad venting is. That is some serious main venting you have already. I have six Gorton 2's and one Gorton 1, and I thought I was overdoing it

gfrbrookline

I have a burnham V904A with a 4" header and two 80' 2" mains. Main vents are 24" before the end of 2 dry returns and 2 drips. I have recently become a convert to Gorton's because tenants played with the ventrites and had one cool apartment. I have one C, two 6's, three 5's, eleven 4's and one unit with two Hoffman 41's and two Danfoss TRV's also with Hoffman 41's.

The Big Mouths are on the return and drip from the front 80' main, it feeds all of the larger radiators. The other main services small bedroom and bathroom radiators and uses the Gorton's. They all heat within 1 minute so well balanced

According to my 0-3 guage I am running at about 2oz. and the heat is very even.

I tried less main venting but this is what it took to get me down to 2oz.

acwagner

I think your main venting is fine. You're at a 12.5:1 ratio for main to radiator venting. Once your main vents close, that's a big jump down in venting capacity and maybe why the 4's and 1A's make some noise.

Curious--does the pressure jump up once the mains close?

I bet you could up each radiator vent one size, keep it balanced, and cut down the noise. But, with 21 vents, that's a big cost to change.

By the way, this is just all fine tuning. I like to experiment with my system and have free rein, but I understand a rental unit is a totally different story.

gfrbrookline

Thanks @acwagner,

The Gorton 4's are on small three and four fin radiators in bedrooms and on sunrad's in the bathrooms, I think if I stepped up the vents it would make the rooms too hot. With the Gorton's I have virtually no noise until the last five or so seconds when they close. Originally they did make noise but then I changed their pitch and they settled down, I had them tipped into the radiator thinking they would drain better, it did just the opposite.

The boiler runs at a constant 2oz. for about 20 minutes then quickly ramps up until the vaporstat shuts it down at 12oz, it may cycle again and run for another 10 minutes or so. I don't usually see more than two cycles, I also don't use setbacks.

I also like to tinker, that's how I came up with my main venting.

gfrbrookline

I chose the Gorton's based on the Gill/Pajek chart using their formula witch adds in the run out so accounts for location and size of the radiator. It is much better than Gorton's chart.

gfrbrookline

I just timed the system, needed somewhere to hide for a few minutes from the entire family after dinner. Boiler on to mains closing in the end of the returns, 7 minutes, boiler operating at 2oz. 12 minutes, time to reach 12oz. 5 minutes. No second cycle today, it's 35 degrees out.

nicholas bonham-carter

I wish there were some simple way to see from across the room, when main vents had closed. Maybe some sort of fan contraption which would revolve in the escaping air, or temperature device causing a light to go on, when steam arrives.
I also have 6 dry returns, with 2 to 4 G-2’s on each.
You are right to compare the aggregate venting resistance of radiator vents to main vents, as that is the key to simultaneous steam arrival. You can start with measuring lengths of main pipe, to have an idea how many main vents to order, but the proof of the pudding is in the low pressure gauge.
Merry Christmas to all of you out in Radiator Land!—NBC

Hap_Hazzard

I keep thinking along the same lines. I’m dreaming about wi-fi capable vents that can broadcast their temperature and status, and pressure control devices that broadcast their pressure and status, so you can see everything on a dashboard app on your computer or cell phone.

nicholas bonham-carter

Even if you could only see the operation of the vents from 20 feet away, it would be an improvement.
That and an automatic oils removal pipe configuration should both be added to everyone’s Christmas list next year.—NBC

gfrbrookline

Merry Christmas to all!

@acwagner I recalculated my radiators an it looks like some of the 4's and 5's are on the upper limits, or slightly higher, so I am going to try bumping them up, 5 in total. Ordered the vents from supply house, should have them on Friday, will update when they are installed.

I do wish there was a 4.5, I know I can drill out the hole but without a drill press that is not an option. If the bedrooms overheat I will go back to Ventrite #1 to replace the marginal 4's. I don't think the occupants are going to turn the radiators off with them and if they set them to 8 it's the same as a 5 so if they complain about being too hot they can turn it down.

Perhaps this will help eliminate the second cycle I have on colder days.

wz25

I'm testing a Hoffman 41 using a street elbow, nipple, and coupling as a 4.5 of sorts. Working well so far-- this replaced a 5 that had a very slight but annoying whistle while venting.

The nipple + coupling give the tongue a bit of additional vertical clearance to extend fully, versus just the street elbow.

gfrbrookline

I installed two 5's and a 6 that I had on hand this morning. My observation so far is that my bedroom is slightly warmer, not uncomfortable, the vents are a little quieter and the second cycle only lasted about 2 minutes and didn't really produce any additional steam to the radiators, it's 31 degrees out.

The other thing I noticed is the 6's don't have a bead of water in front of the vent hole anymore.

When the tenant in the unit furthest from the boiler comes home from vacation I think I will up the C and 6 in her unit to D and C and see how the radiators behave. I had them set up this way before but with smaller downstream venting and they were cool in the center.

I was previously going off the vent your radiator's slowly principle, maybe I went to slowly and with more robust venting system wide they will all heat fully, proportionally and the whole building will heat faster and I can save a little fuel.

Thank you all for your help.

gfrbrookline

So I bumped two more of the 4's up to 5's and everything seems a little quieter, no water beading on the vents which is a plus, will see tonight how the bedrooms are, still thinking they will be on the warm side. I would time the boiler but it is in the 40's right now so it wouldn't be accurate.

gfrbrookline

@acwagner,

I now have 1 D, 3 C's, 1 6, 3 5 's, 4 4's, 2 hoffman 41's and two TRV's with Hoffman 41's. The vents are much quieter and the boiler does not cycle as much, I usually ran two or three cycles, now have one, or one plus a short burst. Will need to tweak the vents a little to re-balance, of course my unit is the hot one, better than cold I guess.

Thanks for opening my eyes. Since the system runs less I should see some fuel savings and less wear on the equipment.

acwagner

Glad to hear it! Sorry I didn't respond sooner--been busy with the holidays.

Now you're closer to 9 to 1 on the main vents to radiator vents ratio. I bet your operating pressure has dropped as well.

I found on my own system I could increase the cycle time on the boiler since the system was faster to respond with larger radiator vents.

gfrbrookline

@acwagner I like the longer cycle run time at, still at 2oz OP, had to adjust 1 c down to a 6 and a 6 to a 5 since my unit temperature spiked up to 76. My unit is above the boiler but on the second floor. The cooler side of the building is responding well to the faster vents.