Hoffman #8's

jamplumb

I am working on an older steam heat @ a church. All of the radiators have Hoffman #8's on the outlet. I have installed replacement Barnes & Jones in these before with no problem. Recently I have found several of the #8's with a smaller orifice than others, not a lot but you can quickly see the difference just by looking. The replacement B&J's nipple is to big to fit into them. After research I found out I may have a "Controlled Heat System" I do not remember if the inlet valve was that type though. The boiler has been replaced, maybe in the 70's? I need to take another look at the system but if it was the Hoffman system it does not have the corresponding boiler room parts probably removed when the new boiler went in. I will check for clues when I go back. I still have the Hoffman #8's problem but also wondering about any other potential problems when the change over was done?
I also have acquired one of the Hoffman heat generators in my last boiler change. Thanks to the wall I know what it is now.

Sailah

For a Hoffman #8 (not an 8C...) there are two models.

Most common uses a PN 2168 and has an integral seat. Diameter of the seat is .239"

Less common is the model 8 CL-1, CL-II this trap has a removable seat and uses PN 3494. It has a larger seat diameter of .479 You need to remove the seat to install this cage unit

Both shown for comparison

jamplumb

Yes I am using the 2168's. Sorry I guess I left that out.

Sailah

OK so if it's smaller than a 2168, let me know the size by using a drill bit as a hole gauge and I'll see what I can come up with.

You have removed the seat in the trap?

jamplumb

Ok, will do. It is not a removable seat. Might be a day or two. Thanks

Steamhead

jamplumb said:

if it was the Hoffman system it does not have the corresponding boiler room parts probably removed when the new boiler went in.

Beavis & Butt-head strike again. We've run into a couple of these where the knuckleheads removed a Differential Loop and didn't leave any way to vent the dry returns. Installing a Vaporstat and proper air vents made a world of difference.

Look for an air vent on the dry return. If there is none you will need to add one (or two, depending on the size of the system) Gorton #2 vent.

jamplumb

I will check when I can get back there. There was also a condensate receiver and pump put in then also. I always wondered why that was installed. The boiler is plenty far enough below the lines. Thanks for the info, I do have the description and pictures for the Hoffman system. I am going to have to look around and see what else might have been changed.

jamplumb

Ok I am back. Sailah, the diameters are 9/32" and 3/16". The 9/32" is the size that works.
Steamhead, I have a video of the system I will post soon. There are no air vents on the system at all. They think the current boiler was installed in the 60's sometime.

Sailah

assuming you are measuring with a ruler vs calipers, the 2168 is the part number you want. I measured the seat with calipers and it's just under 9/32"

jamplumb

Thank you, I was measuring with drills. I know that the 2168 will work with the 9/32" diameter. My problem is the #8's with the smaller 3/16" diameter orifice.

Sailah

Hmmm, 3/16" is absolutely tiny for an orifice. We don't even make any cage units with a hole that small. That's prone to plugging. Can you take a picture looking down in the trap? I can make a custom cage unit with an orifice that small but I need to see how the bottom of the trap slopes because of the extended seat on the Hoffman #8.

Right now 1/4" is the smallest orifice I make in 1000's of cage units.

Sailah

Actually what I would do is just drill out the orifice for a 2168. It'll be faster for you and make a better trap. Plus all the part numbers will be the same.

jamplumb

That is what I was hoping to see, much easier all around. I was a little reluctant to do that without a consensus.

Sailah

You should have plenty of meat in that trap to punch it out

jamplumb

Ok, thanks.