Gorton #2 or Hoffman 75

alanm

One pipe steam heat system

Which main vent is better?

Thanks Alan

ChrisJ

Multiple Gorton #1's as they appear to be more reliable.

I could never justify the cost and vent rate of a Hoffman 75.

dabrakeman

More venting for the money with the Gorton #2. Have you calculated your venting needs (length and pipe size of the mains)?

alanm

right now…i have a Hoffman 75 at the end of the main (in basement)…..really dont feel like drilling into pipes to add another main…any other suggestion…the Hoffman 75 has not been changed for about 7 years.

thanks

dabrakeman

Again, what are the main pipe sizes and lengths. From that we can determine how much venting is needed. Is the current Hoffman vent working? Unless it is seeing very high pressures or getting water thrown up into it the valve should last well past 7 years.

With no other information and if you are willing to spend $180 on a Hoffman 75 I would just spend $145 on a Gorton #2, get more than double the venting but you would need to add a reducer since the #2 has 1/2" threads whereas the Hoffman had 3/4".

alanm

i am getting some water in the radiator valves…..off of the boiler…i have one main that takes care of about 12 radiators thru 3 floors…and then for some reason…another run off the boiler only goes to 3 radiators (one on the 1st, one on the 2nd and one on the 3rd floor).

Steamhead

@alanm , how long is the steam main, and what pipe size is it? Without the answer, we can't advise you.

alanm

in the basement, there is about 120 lf of main…..the pipe..hard to tell, as it has insulation and then taped wrapped…but the dimension over that is about 15".

thanks

dabrakeman

I assume "the dimension" you are referring to is the circumference measure? If so and if the insulation thickness is 1" then likely your mains are 2.5" (pipe OD diameter of 2.875") but please try to clarify these assumptions. Also, you had mentioned before that you have 2 mains so we would need to know the length of each individually from header to vent locations at end of the mains to calculate the internal volume of each main.

109A_5

I have a 1 pipe system, so far I like my Barnes & Jones Big Mouth.

https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Barnes-&-Jones-BJ-3BM-Submittal-Sheet.pdf

109A_5

" right now…i have a Hoffman 75 at the end of the main (in basement)…..really don't feel like drilling into pipes to add another main…any other suggestion…the Hoffman 75 has not been changed for about 7 years. "

If there is enough vertical room you can remove the Hoffman 75 and build a manifold or 'antlers' to add more than one vent, if desired.

" i am getting some water in the radiator valves "

Boiler water clean, water level stable when steaming ? Pipe pitch correct ?

alanm

See photos…so from the boiler…one main ( that is the piping on the far left) goes off and feeds 18 radiators ( 6 on first floor, 7 on 2nd floor and 5 on third floor) and there is 90' of main in the basement before branching off to these radiators. .. the other main (piping in the middle) is about 7'…and it branches off to 3 radiators— one on each floor…no return on the main. now, the piping at the bottom right…is the retun for the main that feeds the 18 radiators and you will see the "green " hoffman". overall the system heats pretty well, but some radiators not getting as warm as expected and some water …all radiators have new vents and all pitched. didnt know if changing the main vent would do anything….and how would i tell if that main vent is working properly? thanks

alanm

sorry ..photos

boiler 1 9.jpg

boiler 2 9.jpg

109A_5

The main vent, closes when steam gets to it and vents air at the rate of the orifice size. With over 90' of main, you may benefit from faster main venting. So 90' of main between the boiler and the first radiator run-out ?

looks like there is enough room for multiple main vents. Steam can be detected with a mirror or a chrome tool or knife held up to the orifice. The flow rate is a bit harder, you need a flow gauge adapted to it, maybe you can hear the air leaving.

" i am getting some water in the radiator valves " Still a bit unclear on this, how do you detect water in the radiator valves ? What kind (brand) of radiator vents are on those radiators ?

" the other main (piping in the middle) is about 7' " Maybe a counter-flow main and needs to be pitched toward the boiler, if it has no other means of condensate return.

dabrakeman

Assuming again that you have 2.5" mains (you really need to verify) with ~3cf of air to eliminate (not including the volume in the return which also needs to be vented given your main vent location) I would add at least a Gorton #2 to the Hoffman 75 you already have on that long main. Two Gorton #2's would be better. It should be easy to construct an antler to put multiple vents where that #75 now is at and they could be raised a bit higher above the pipe as well. As @109A_5 said you can monitor a cycle, listen for air being released from the vent and wait for the steam to get to the vent (it will get too hot to touch) and then verify that it is not releasing steam. If it does release steam it is failed/stuck open. If you can't tell whether it is releasing air or don't notice any changes in sound when steam gets to the vent I would take it off and try blowing through the bottom with it upright to make sure it is not stuck closed.

So is there any main vent on the short 7" main or is it being vented entirely through the radiators? Are any of these radiators off the short main getting water in them? Which radiators are getting water? Do the radiators off one of the mains start heating noticeably faster than off the other?

Mad Dog_2

Hoffman products are very high quality, as are Gorton. The greater air expulsion rate of the Gorton #2, which is in the same price range and close in height, make it the better choice in most cases. Mad Dog

alanm

regarding your question if there is any main vent on the 7' main run …no just the vents on the radiators for those 3…no return just the main branching off to the 3 radiators. Yes..those 3 radiators are the ones that get water and are slower in heating.

dabrakeman

Check the pitch on the 7' main as well as any horizontal runs going to the radiators. All should pitch back to the boiler at >= 1" drop per 10ft pipe length. You may try raising the three radiators a half inch or inch if you have any play in the riser pipe to the radiator.

alanm

that main does have a pitch before it goes into the wall leading to the other floors and there is no play in riser pipe..all radiators do pitch also back to riser. since that 7' main does not have any return nor any main vents…i guess changing the hoffman 75 main vent for the "other main" wont do anything…any suggestions for that short run?

109A_5

" that main does have a pitch before it goes into the wall leading to the other floors "

Pitched which way ? It need to drain towards the boiler, this appears to be a counter-flow main, steam goes in one direction the condensate goes in the other.

Your other (longer) main is a parallel flow main the steam and the condensate both go in the same direction.

At this point venting the long main faster may make the heating of the short main worse depending on the actual problem.

If steam has to push its way through a main that is pitched the wrong way and trapping condensate that restricts the steam flow.

You could add a main vent at the riser end of the short main or at the top of the riser.

You want the mains to vent as fast as possible yet balanced also, so the house heats evenly.

alanm

thanks…so the short main is pitched back toward the boiler….so since the long main seems to be heating all the other radiators fine….just keep the hoffman 75 alone? corection about the "short main run"….it only feeds 2 radiators…one on the 2nd and one on the 3rd…they are the ones that dont heat well and have water…where do i put a vent (this one has no return?). if you look at the photo..right above the Hoffman/green and to the righ, is a branch off the short run that goes to a first floor radiator…this one also gets water and doesnt heat well. suggestions? thanks

dabrakeman

What radiator vent types do you have on the 2nd and 3rd floor radiators off the short main, and are they working/not full of water? You could consider adding a main vent up on the third floor but I would try seeing what happens if you remove the third floor radiator vent first to see how quickly (or not) steam gets up there compared to baseline. What bothers me is that if you are getting water up there then steam already is trying to get there but it would insinuate that water is blocking it somewhere, or you are getting a lot of water thrown up into the mains. Is there alot of surging in the site glass when the boiler is running?

Steamhead

https://forum.heatinghelp.com/discussion/comment/1865944#Comment_1865944

Upgrade the long main to a Gorton #2, and see how both mains do after that.

alanm

when i take the 3rd floor vent off….steam gets up there quickly… site glass /water stays level…

Jamie Hall

https://forum.heatinghelp.com/discussion/comment/1866704#Comment_1866704

If steam moves quickly with the vent off, but not with it on… the vent is either stuck closed or too small.

alanm

vents are new…i have tried adjustable hoffman and regular vents….those 3 radiators on their own main seem to get hotter when i remove the vent……will changing the main vent from the other run do anything? i dont see how. thanks

109A_5

So is it 2 or 3 radiators on the short main ? Probably don't matter much but it seems like it keeps changing.

Anyway you mentioned a riser, from the short main in the basement do each of the multiple radiators have their own run-out from the basement ? Or it there a single vertical riser that feeds the multiple radiators ? If a single vertical riser a main vent at the top of the riser may help.

What brand radiator vents are on the problem radiators ?

dabrakeman

If the 3 radiators are heating quickly enough with the 3rd floor vent removed and if you have already tried variable Hoffman 1a's all the way up on setting 6 (equivalent to a MoM #6) on those radiators and they don't heat sufficiently then it seems the system could use a main vent mounted off the riser on the 3rd floor.

109A_5

Assuming a single riser is on the short main, if it was my system, I'd move the Hoffman 75 to the top of the riser. I'd then put a Barnes & Jones Big Mouth at the end of the 90 foot main. If you don't like the Barnes & Jones Big Mouth (some folks don't) I'd use 1 or 2 Gorton #2 at the end of the 90 foot main. I don't like to burn fuel just to push air out of the system through main vents that are more restrictive than they need to be.

Vent flow characteristics in this document.

https://heatinghelp.com/assets/documents/Balancing-Steam-Systems-Using-a-Vent-Capacity-Chart-1.pdf

alanm

thanks…

simon_skove

can the gorton #2 be used on the dry return near the boiler as well? Two pipe vapor system here.

109A_5

https://forum.heatinghelp.com/discussion/comment/1873077#Comment_1873077

They are commonly found there. Just in case steam gets into the dry return you won't loose much water. However if you have steam in your dry returns you may have other issues.