Question about water hammer and near boiler piping

Abracadabra

Are the radiators that are slow to heat, fed by the main that has it's riser downsized off the header?

ChrisJ

Besides main vents as I said previously with an undersized boiler you will never get all of the radiators to heat evenly using Gorton Cs or varivalves. That's often impossible even with an oversized boiler.

Horribly slow main venting and ridicules radiator venting is 80% of your problem right now in my opinion.

Those mains need to be vented fast and the radiators need to be slowed way down otherwise a few will continue to hog steam. Buy a bunch of Gorton #2s for the mains and a few Gorton 4s for the radiators. Leave Gorton Cs on the ones that don't heat and put the 4s on the ones that do and watch the magic. When you find some still continue to heat faster than others slow those down to Gorton 5s or 6s.

Others may be right, maybe the boiler is just too small but I don't think you'll know until you fix your venting issues which need to be fixed anyway.

schwec

ChrisJ said:

Besides main vents as I said previously with an undersized boiler you will never get all of the radiators to heat evenly using Gorton Cs or varivalves. That's often impossible even with an oversized boiler.

Horribly slow main venting and ridicules radiator venting is 80% of your problem right now in my opinion.

Those mains need to be vented fast and the radiators need to be slowed way down otherwise a few will continue to hog steam. Buy a bunch of Gorton #2s for the mains and a few Gorton 4s for the radiators. Leave Gorton Cs on the ones that don't heat and put the 4s on the ones that do and watch the magic. When you find some still continue to heat faster than others slow those down to Gorton 5s or 6s.

Others may be right, maybe the boiler is just too small but I don't think you'll know until you fix your venting issues which need to be fixed anyway.

Before, when I said I added Gorton C's and VariValves, that was only on the problematic radiators that aren't warming. Those 6-8 radiators are furthest from the boiler and are mostly on the second and third floors. The first attempt was to try to speed them up. Some of them had Gorton 6's, which I exchanged. The rest of the house has a mix of Gorton 4-6's and a couple of adjustable vents(they have the round dial on the top) set at either 1 or 2 out of 10. Those vents generally get faster the further away the radiator is from the boiler.

The next step is to add additional venting on the mains.

ChrisJ

schwec said:

ChrisJ said:

Besides main vents as I said previously with an undersized boiler you will never get all of the radiators to heat evenly using Gorton Cs or varivalves. That's often impossible even with an oversized boiler.

Horribly slow main venting and ridicules radiator venting is 80% of your problem right now in my opinion.

Those mains need to be vented fast and the radiators need to be slowed way down otherwise a few will continue to hog steam. Buy a bunch of Gorton #2s for the mains and a few Gorton 4s for the radiators. Leave Gorton Cs on the ones that don't heat and put the 4s on the ones that do and watch the magic. When you find some still continue to heat faster than others slow those down to Gorton 5s or 6s.

Others may be right, maybe the boiler is just too small but I don't think you'll know until you fix your venting issues which need to be fixed anyway.

Before, when I said I added Gorton C's and VariValves, that was only on the problematic radiators that aren't warming. Those 6-8 radiators are furthest from the boiler and are mostly on the second and third floors. The first attempt was to try to speed them up. Some of them had Gorton 6's, which I exchanged. The rest of the house has a mix of Gorton 4-6's and a couple of adjustable vents(they have the round dial on the top) set at either 1 or 2 out of 10. Those vents generally get faster the further away the radiator is from the boiler.

The next step is to add additional venting on the mains.

Ah ok.

I think you're right, main venting is your only hope at this point. I would do as @KC_Jones‌ recommended with 5 or 6 Gorton 2s per main. Even if the boiler gets switched those vents will be necessary so it can't hurt. They're expensive up front but believe me they will pay for themselves over time.

schwec

Abracadabra said:

Are the radiators that are slow to heat, fed by the main that has it's riser downsized off the header?

If you look closely at the elbow that connects the header risers to the main supply, one side has an elbow with a reducer that the riser connects to, the other has an 8" segment of 3" pipe that the riser connects to. During installation, they tried, but we're unable to remove that 3" segment.

Yes, the part of the house that is slow to heat is the side of the house that has the 3" pipe segment in the riser.

Abracadabra

schwec said:

Abracadabra said:

Are the radiators that are slow to heat, fed by the main that has it's riser downsized off the header?

If you look closely at the elbow that connects the header risers to the main supply, one side has an elbow with a reducer that the riser connects to, the other has an 8" segment of 3" pipe that the riser connects to. During installation, they tried, but we're unable to remove that 3" segment.

Yes, the part of the house that is slow to heat is the side of the house that has the 3" pipe segment in the riser.

Try using slower main venting on the main line that all radiators heat well and very fast venting on the slow main. Try to push the steam into the slow main first. See if that helps.

KC_Jones

I am guessing those risers up from the boiler are only 2" based upon the fittings used. I don't have Dan's book in front of me to look it up, but each pipe size is rated for supplying a certain amount of BTU's. In addition to the boiler under sizing I am guessing those 2" pipes MIGHT be restricting as well. If you have 2 1/2" mains it should be 2 1/2" all the way to the header. If your boiler is under sized and that isn't going to be changed I would for sure get those risers changed no matter what. As far as not being able to remove the 3" pipe that shouldn't be a problem at all. The 2" pipe could very well be an issue. I suspect the installer did 2" because of wanting to use those press fittings instead of threaded pipe. Are you planning on getting the installer back to correct the mistakes they made?

KC_Jones

Abracadabra said:

Try using slower main venting on the main line that all radiators heat well and very fast venting on the slow main. Try to push the steam into the slow main first. See if that helps.

If you look at the earlier posts by the OP they essentially have no venting on the mains, 120' of main total and 2 Gorton #1 vents total. All that is doing is forcing the steam to go no where. All the mains need sped up big time even the one that is "heating well" which to me is relative when they are talking about hours to get heat. Even at the lengths of those mains they should be able to fill them in minutes with proper venting.