Cold rooms at furthest pt from boiler. Solutions?

Jells

My tenant on the 3rd fl is complaining about the furthest rooms being cold. I believe I've already sized up their Maid-o-mist rad vents and sized down the vent in the room in the 2nd fl unit with the thermostat. Can a vent side TRV help with underheating? What about if I put a Gorton 2 in a Tee inline between a rad and it's valve there, bringing up the steam ASAP? The main for that line serving 5 rads is a Gorton 2 in the basement.

It's frustrating, no matter how many times I explain how steam works and the problem is not the thermostat setpoint, they still beg me to turn up the thermostat!

Jamie Hall

Yeah... if you want more heat, turn up the thermostat...

Adding a vent on whatever riser is feeding their radiators will help, probably a lot. I'd not try to put it between the valve and a radiator, though -- remember that that connection is a matched union. But if there is a convenient spot at or near the top of their riser, that would be great.

A TRV won't help underheating a lot. For one pipe steam, they can only reduce the heat from a radiator, not increase it.

Jells

Thanks Jamie, I'd be putting the tee between the Spud and the radiator. I was just examining the system and, unfortunately in the two front rooms that are cold the risers split in the basement rather than each teeing off of a single riser. So adding venting to one will not directly help the other though it will help vent the main line in the basement faster. 

I wonder, is there any way to test that Gorton to make sure it's functioning properly? Or even the maid o mists. The rad at the bottom of that stack with a small port was not hot at all after a boiler cycle just now though the riser next to it was perfectly hot.

Jamie Hall

It does sort of sound as though the vents may not be working. They should release air at the beginning of the cycle, until the radiator is pretty hot across. It may be hard to feel the air coming out, but you might notice it with a strip of tissue paper or it it's available, a bit of smoke...

HVACNUT

I dont know much about steam piping, but I do remember something to the effect, steam doesn't care about heat loss, its only job is to get to the last radiator before condensing. 
What changed from the original piping?

Jells

HVACNUT said:

What changed from the original piping?

Of course, that is the question. The only thing I can think of is vent failures. Or the idiotic tenants don't know how to properly close a window. I inspected the radiator in unit below,  it had the biggest port, a C I think, and the tenants had a window cracked because it was too warm. So what else but a valve failure could cause that difference between adjacent floors? They weren't home today and I don't like to go in without the tenants present unless it's really important, I'll inspect it tomorrow.

ethicalpaul

It's frustrating, no matter how many times I explain how steam works and the problem is not the thermostat setpoint, they still beg me to turn up the thermostat!

Probably almost as frustrating as paying rent and still freezing.

if you want to see how a D MoM vent would be, you can remove the orifice from the top of any of them.

Jells

ethicalpaul said:

It's frustrating, no matter how many times I explain how steam works and the problem is not the thermostat setpoint, they still beg me to turn up the thermostat!

Probably almost as frustrating as paying rent and still freezing.

if you want to see how a D MoM vent would be, you can remove the orifice from the top of any of them.

Despite being a money grubbing heartless landlord, I'm not a complete idiot. Yes I've done that. But turning up the thermostat so that everyone else needs to open their windows is idiotic and irresponsible to our troubled climate.

ethicalpaul

Of course, but you can’t really expect the tenants to understand or care about the operation of steam heating systems, whether they are “idiotic” or not.

I am a little confused about your situation though... at first you said it was third floor rads that were not getting hot.

but then I think you said it was a first floor rad that was totally cold. Regardless probably the fastest test is to remove a vent then cycle the heat and see if air then steam comes out. 

Time from the start of the cycle to when air starts coming out then from that point to when steam starts coming out. Log the times on a map of your system. It will help you learn what’s going on.

while the vent is off, blow gently into it. It should let air past. Try it upside down (the vent, not you). A Gorton or MoM should then block the air.

Jells

ethicalpaul said:

Of course, but you can’t really expect the tenants to understand or care about the operation of steam heating systems, whether they are “idiotic” or not.

Note: I did NOT say the tenants were idiotic, I said MY turning it up so other tenants had to open their windows would be.

ethicalpaul

Of course, that is the question. The only thing I can think of is vent failures. Or the idiotic tenants don't know how to properly close a window.

My emphasis But don't think I don't sympathize with you. I have been a landlord too. But I've also been a tenant with bad heat, 30 years ago. I jumpered the thermostat...just be glad I'm not your tenant

nicholas bonham-carter

It sounds like your main venting needs some improvement, so that steam can arrive all the rads simultaneously.--NBC

Jells

ethicalpaul said:

Of course, that is the question. The only thing I can think of is vent failures. Or the idiotic tenants don't know how to properly close a window.

My emphasis But don't think I don't sympathize with you. I have been a landlord too. But I've also been a tenant with bad heat, 30 years ago. I jumpered the thermostat...just be glad I'm not your tenant

Fair, I guess I forgot that post. but seriously, you wouldn't believe how many times I've seen people complaining about the heat who haven't closed the windows so the sashes seal.  Or removed their air conditioners. I had a woman standing there in shorts and a tank top in February complaining that her apartment was only 70°.  In fact just now I went up to the complaining apartment, and all four windows in those two rooms were not properly closed and locked. Who complains that their apartment is in the low 60s and doesn't check their windows for leaks???

Nick, the main vent for that line is behind the wall of a basement tenants apartment. It's not something I can screw with easily. That's why I was thinking about putting the Gorton 2 up on the top floor. But I think the Gorton is shot, if I tip it up toward the ceiling and try to blow through it I can't blow a thing. I do have a Hoffman 4A I can try, though it doesn't have the throughput of the Gorton.

Jells

So I've got some real bizarre data collected. Take a look at this graph, you can see it full size by opening it in a new tab. The dataset market 'Living room' is the rad on the 1st floor closest to the boiler. The one 'front bedroom' is on the riser on the 1st floor furthest from the boiler. On that front riser there's a Gorton 2 on the basement main, then the main splits into 2 risers for the 2 front bedrooms on the 2nd & 3rd fl (none on 1). Master br on all 3 have MoM with either no port or a D. Sm BR on 3 has a MoM with a D and a Hoffman 4A.



So you can see that before I added the 'front bedroom' sensor the LR riser was giving nice even waves of heat, and after it was placed the peaks were equivalent and nearly simultaneous. Then about 9 AM on the 16th that front riser just shuts down for 19 hours! There's 2 rads on that line with very open MoMs on them. After that event, the heat in front peaks higher than it did before. Now, the LR thermometer was sitting on top of the valve handle and the FBR is actually on the riser pipe, but its an odd artifact.

My biggest question is what can cause a whole line to miss entire boiler cycles like this does in several episodes, some only a cycle or 2 but the big one for 19 hrs.

I think I need several more of these thermometers to place on the other risers and perhaps rads. Even at $30 they're cheaper than getting in a 'pro' and more likely to result in success. I just can't see a steam pro taking the valuable time to really figure this out.

FWIW here's the layout of the place. There's no 2nd BR on the 1st floor.

Jamie Hall

I have to admit that with my complete lack of confidence in modern gadgetry, my first question would be... is this an artifact? If that radiator/riser had been off for 19 hours, that radiator should have been stone cold. Was it?

There are some other curious features. During the longer quiet interval in the middle of the graph, the reported number does have the cycles, but at very much reduced amplitude, and does track the minimum of the other sensor. Is this real? There is also the 10 degree (more or less) offset in the peak temperatures reached by the living room sensor starting near the beginning of that gap and continuing after that.

Further, since this is steam heat, the sensors -- neither of them -- can be reading the actual temperature of the pipe or the radiator -- the reported temperatures are much too low for that.

Bottom line -- first thing I'd check is whether those sensors are lying to you or not. Then I'd verify that that bedroom radiator is, in fact, completely failing to heat (even for one cycle, never mind 19 hours). Then I'd start looking for why that could be.

Jells

The tenants complained the heat was off in that room! They think I have the heat on timers and turn it off at night, I keep having to explain it's just an unprogrammed thermostat in the 2nd fl LR.

I don't think the sensors are lying, but obviously the temp is relative to placement. I'm going to be careful from now on to make equivalent placements. However he beginning of the graph is pretty confidence inspiring, very in synch and similar temps.

That said, I do think more sensors would help. There's just so many 'artifacts'. Yesterday I noticed the 1st floor BR rad cold but the riser hot, and the cycle had started 45 min earlier. Obviously I'm at a disadvantage not actually living there. I'm currently renovating the 1st floor which makes it great for access to those rads and risers.

What I don't have is a good idea of what would cause these missed cycles. What would cause a vent valve to just lock up? I think my next tweak is to use a 1/8" tee and double the MoM on the 3rd fl BR rad.

Jells

Here's another possible issue, am I overpressure and why? I had it services and cleaned by a pro last year, but I have never dived into the pressure settings and all the issues around it. Can overpressure cause the vents to lock up?

neilc

ding, ding, ding, ding, ding, ding,
I think you found a winner,
if that gage is reading correct, then you better get to checking the pigtail for clean and clear back to the boiler,
which might be problematic as it looks like the skim nipple(?) is installed to interfere with removing the pigtail,
remove the Ptrol and see if you can blow thru the pigtail back into the boiler,
and yeah, if that pressure is that high you could be jamming up vents all over the place.

Jells

neilc said:

ding, ding, ding, ding, ding, ding,
I think you found a winner,
if that gage is reading correct, then you better get to checking the pigtail for clean and clear back to the boiler,
which might be problematic as it looks like the skim nipple(?) is installed to interfere with removing the pigtail,
remove the Ptrol and see if you can blow thru the pigtail back into the boiler,
and yeah, if that pressure is that high you could be jamming up vents all over the place.

OK, thanks. Does this pic help tell if the skim is interfering? I've never messed with the pigtail.

neilc

time to mess with, or replace the pigtail,
from the first picture it looked like the pigtail would hit the large nipple as you unscrew it from the boiler, and you would have to remove the large nipple first.
this last picture looks like it may miss as you turn it out,
without being there , , , I am not sure.

but before dealing with the pigtail, just remove the Ptrol and see if you can blow thru it back to the boiler, the pigtail loop must be clear.

Jamie Hall

As @neilc says, if that gauge is even remotely correct, that could well be it. A vent is supposed to close when either water or steam hits it. It will not reopen, in general, until the pressure drops to zero or very nearly to zero. Further, some vents -- most, in fact -- have a maximum working pressure of 3 psi. Over that, and they can and do close -- and simply won't reopen. They get stuck. Sometimes, after a few cycles, they relent. Sometimes not.

Furthermore, vents from different manufacturers behave differently in that regard.

Jells

So if the tube is clear is there anything else that could be causing the over pressure? I guess when I get back there tomorrow I need to open it up and see what the inside differential setting is as well as clear the tube.

neilc

Ptrol could be bad,
Gage could be bad,

have you seen the gage read 0 when the boiler has been off, or cold ?

ratio

Are the sensors …uhhh… firmly attached? I can't help but think that if I were suffering from under heating because of a "money grubbing heartless landlord", I might be tempted to tamper.

mikespipe

Just want to add a question. Are your pipes insulated? long runs with pipes that have had the insulation removed are very problematic with steam condensating well before it gets to the end of the run. also shrink the first floor MOM air valve down to a 5 or 6. that may help the steam reach further

mikespipe

Also I don't see pipe insulation on the header . every pipe is a radiator I recommend !1 inch thick fiberglass insulation on every steam and return pipe in the furnace room and in any room that is not occupied. the savings on your heating bill more than covers the cost of the insulation. and it pays for itself probably every year.

Jells

@ratio The sensors are in the 1st floor that I'm renovating.

@mikespipe The headers right above the boiler aren't insulated but the rest of the mains are. Fact is the warm basement acts as effective radiant for the 1st floor. I'm OK with the heat bill I have. When I bought the place in 2012 the seller said this 3 unit rowhouse plus a basement apt was burning $12k in oil a year! I figured that they were doing something wrong, converted to gas with a new boiler by former HH member J-Star, and have it under $3k.

I think they were keeping it tropical too, that 1st winter after the new boiler a tenant calls saying they're freezing. I ran up there thinking something failed, but she's standing there in a 70 degree apt in shorts and a tank top. When I tell her it's winter and maybe she should put on some clothes, she screeched "THAT'S ****!!" Landlording is fun.

Jells

So more progress but not definite solution yet. I get there and it seems to be in early cycle. I shut it down and watch the gauge. No movement. I try and blow the pressure relief, no hiss! I close the sight glass valves, pull the sight glass that needs cleaning and crack the valve...nothing. The gauge still reads 12psi! The gauge is toast.

I pulled the gauge and tried to rinse it out with vinegar, no dice. Going to buy a replacement tomorrow. I pulled the pressure control, cleaned its port and cleaned out the pigtail with an 18" flexi test tube brush I found in my archives. So it's now clean & clear. The 'difference' inside was set to 1.

I also managed to break the damn sight glass. Grrr. So I skimmed it and turned off the autofill, figuring it'll be fine till tomorrow.

Question: Would a 15 psi gauge be better than a 30?

neilc

with no sight glass, how do you know your water level right now?
kinda critical , , ,

you need the 30 to keep code and insurance people happy,
you should add a low pressure gage to the mix,
a 15 is ok, but most here will say a 3 , or I found 5s I like.

could you tell if the pigtail was clogged or not?

Jamie Hall

You're not the first to break a sight glass. Why people learn to always have a spare before they mess with it.

Follow @neilc 's comments on the pressure gauges.

Jells

neilc said:

with no sight glass, how do you know your water level right now?
kinda critical , , ,

you need the 30 to keep code and insurance people happy,
you should add a low pressure gage to the mix,
a 15 is ok, but most here will say a 3 , or I found 5s I like.

could you tell if the pigtail was clogged or not?

I'll see if I can do that dual gauge setup. It was a little hard to push the brush through, but I couldn't say for certain if it was clogged. As for level, it was at skim level when I left, and should be good just for overnight. If it lost that much water I'd have other problems!

Jells

Jamie Hall said:

You're not the first to break a sight glass. Why people learn to always have a spare before they mess with it.

Follow @neilc 's comments on the pressure gauges.

I'm probably not the 1st to think a system just with plugs to enable cleaning of the glass in situ would make more sense, huh?

Jells

Sight glass and spare purchased, along with new sealing gaskets and a 30 psi gauge, my local heating supply did not have 3 or 5.

So now after watching an entire heat cycle I can't register any pressure at all! I double checked that the port was clean & clear, and even check the gauge was working by blowing in it, I can produce 3 psi. Lifting the pressure relief produces no hiss either, there is really no detectable pressure, though the radiator are getting hot. Is that a bad thing, do I have too much venting going on?

Jamie Hall

You're just fine. A reasonably closely sized, properly vented boiler will produce at most a few ounces per square inch pressure until all the radiators are filled -- and then it's time to turn it off.

That's why you have to have a 0 to 3 psi gauge -- 0 to 30 is never going to even flicker.

Jells

Jamie Hall said:

You're just fine. A reasonably closely sized, properly vented boiler will produce at most a few ounces per square inch pressure until all the radiators are filled -- and then it's time to turn it off. That's why you have to have a 0 to 3 psi gauge -- 0 to 30 is never going to even flicker.

Thanks. I guess we'll see if I get any more stuck vent artifacts in the heat cycles. Tracking down a 3 psi should be interesting, even Supplyhouse.com only has 5 psi.

Jamie Hall

Amazon is your friend...
https://www.amazon.com/Kodiak-Controls-KC25-3-Pressure-Gauge/dp/B00H9ZWLZG/ref=sr_1_3?crid=R0969251O0T3&dchild=1&keywords=0-3+psi+pressure+gauge&qid=1608591211&sprefix=0+to+3+psi+p,aps,506&sr=8-3

Jells

So, it looks like clearing the pigtail Sunday afternoon may have done the trick! The rads seem to be behaving. But can someone explain why? How was it ever getting overpressured if it can't even get the 3psi gauge I added to budge off it's pin?

neilc

if that boiler was making 10 / 12 psi, vents were likely locking up, the pressure was too great to continue releasing the air ahead of the steam, and far radiators, or any of them for that matter, stayed cold, instead of accepting steam and making heat.

neilc

Or, , , ,
if that pigtail was clogged and the Ptrol was not reacting to the boiler pressure, and you were making that same big pressure , , ,
with the pigtail clear, are you cycling on the Ptrol ?
and running at 0.5 to 1.5 ?

Jells

@neilc Problem is I don't really know what pressure it was, the gauge was frozen at 12. But if the venting is so wide open the new 3psi gauge doesn't budge, how was it ever building up enough pressure to jam the vents? The Ptrol just cuts the flame if pressure gets too high, right?

Jamie Hall

I don't have a really good answer, but it is worth remembering that if a vent closes and is then subject to a pressure over its working pressure (usually 3 psi) it may lock shut -- and not open when the pressure drops back again. After a time, when it is really cooled, it may snap open again -- although sometimes a gentle (?) tap is needed.