What the...

Paul Fredricks_3

Our guys did an install the other day. The customer is complaining of hammer. Checked it out today and hammering everywhere. They have 2 mains. The first has no return. Judging by the pitch it is a counterflow main. The other is a more traditional with a return at the end of the main. The installers missed this and, I think, they removed the drip for the counterflow, not realizing what it was. The returning condensate is flooding the header, and then it;s all pushing up into the rest of the system.



Has anyone seen a hybrid like this before? 

Charlie from wmass

Yes but not too often

If it is a counter flow add in a drip and make it all quite. Remember not all dead men were highly skilled and the slow fire of the old boilers let them get away with a lot. also could be a case of them having had hammer all along and now they have a person to blame. But catching it as you did and it being a relative easy fix should make you feel good. I like when I catch my mistakes early, makes it easier to unthread the fittings and fix them.

Unknown

Mixed System

There was one in a post about 10 days ago with two parallel mains and a weird counterflow main. 

http://www.heatinghelp.com/forum-thread/129758/Steam-Boiler-2-drains-one-for-Condensate-Return#p118851

The owner was complaining about hammering. The copper boiler piping is recent but the weird counterflow setup looks like it has been there a while.  I think Charlie is right that you could get by with a lot more in the old days with the "slow fire" of coal.

- Rod

Paul Fredricks_3

yep

I asked the customer if it used to take a lot longer for the heat to come up and she said yes.



On top of that issue, there is no insulation on any of the steam pipes. She says it's been like that since they bought the house 6 years ago.



I'll go back today for a parts list.

Paul Fredricks_3

and

The end of the counterflow main is buried in a wall, as best I can tell. I assume there's a main vent on the end, somewhere. I think the return may be plugged as well.



Charlie, I hear what you're saying about the problem always being there. I have thought that same thing myself many times. But each time I was able to find and correct the problem, which was install related. I'm sure someday I'll hit one that must have always been like that and the customer is telling me "no". Especially along CT's gold coast. Nice folks there



Rod, do you think I can just drop in a Tee for the drip, or should I pipe it like a drop header as shown in TLAOSH?

Steamhead

The tee will work

as long as the drip connection is the full size of the main. Screw a short nipple into this and then reduce it. This will make sure it gets all the start-up condensate.

Paul Fredricks_3

ah

Perfect. I was hoping that would be the way to go. Thanks Frank.



When this system is steaming, the water in the glass drops down to nothing. Do you think this is related?

Steamhead

Yup

the condensate is being held up in the mains. This also causes the banging. 

Paul Fredricks_3

another question

The Hartford loop comes off the equalizer as it should, drop about 6", then runs horizontally about 2', then drops a foot to the return. Is this stepped drop OK, or does it need to go right to the floor?

Charlie from wmass

A great place to use those bull tees

I was just thinking this is one of the few times a bull tee would be a good choice. Granted a full size tee as Frank said will be perfect. I have all these old bull tees I need to find a home for them somewhere. A good flush and skim may help too.

Paul Fredricks_3

yup

Skim is already done. Need to flush the return.

Paul Fredricks_3

Update

Here's the pic with the drip installed. You can see the pitch of the counterflow main to the rear. On the return the 1/2" copper isn't pressing against the drip, though it looks like it is.



Quick repipe this morning and no hammer from cold to all radiators hot. Thanks guys!