boiler design and zones

TerrS

@neilc I am actually trying to figure out how to do that and infrared scanning. It's not apparent apparently.

neilc

as someone above suggested,
check with your electric utility suppliers,

hot_rod

https://www2.illinois.gov/sites/KeepWarm/Pages/Audits.aspx

It would still be nice to have an accurate heat loss calc done, we are all speculating on that number

Possibly some of the energy audit companies do that?

pedmec

does anybody know what boiler this is? i cant find whether she has indicated oil or gas. nothing here makes any sense. reread some post. 45-50 minutes to heat 52k BASEBOARD to 180 with a 115k btu output boiler

hot_rod

It had been a bit confusing to follow. Early in the thread there was 115’ of fin tube total
Now it has panel rads and a kick space heater also, hard to pin down the amount if radiation connected to the 113k boiler

If the boiler shuts off on design days then it is larger than the connected load.

But it struggles to get to 180 with the circ not running??

Sounds like a hydronic twilight zone

pedmec

Sorry, missed the pics. Might be on here too much. Everything is starting to look the same lol

TerrS

@hot_rod lol. As I learn and miss things I add them. But I can guarantee there is no more as I walked my whole house as of writing and measuring.

So the boiler is a carrier PW51 - 150k input, and 113output, according to the boiler plate.

And your right, how long does it take to make 13.8 gallons of water 180 degrees. My current is 40 minutes as follows..

Attic run..

30ft of fins to the attic and its a 70ft round-trip of piping which in a 3/4 pipe. Is 2.3 gallons.

2nd floor

41 ft of fins and 58ft of round-trip piping of that 3/4 pipe is. Still 2.3 gallons.

So 4.6 gallons

First floor

33ft of fins, plus a 3' buderus and kick and only 30ft rt but most of this is 1" pipe, so right around 2 gallons. 1.2 gallons in the 30ft of pipe and .75 gallons in the fins, etc.

Basement

20ft of fins plus 30ft of 3/4 pipe is 1.2 gallons.

So yes I forgot about my basement because I removed 10ft at one point.

So 124ft total fins plus all the supply/return lines.  Obviously I can't measure all this but I know my 3rd floor is 35ft up from basement and subtracted 11ft every floor I dropped. Plus some run my length of my house before they go up/down. But there are in the ballpark.

But even still what you are telling me, you say doesn't make sense. As I asked before. I have a big pot of water that starts at 6 gallon from the only spec I found for tank size. Then I add in the 7.8 gallons in my runs, because my circulator only has a 2minute delay before everything starts mixing. So 64degree water slowly being heated. Like I said before it's around 25-30 minutes to get to 120 degrees and the reason I know that is because the kick starts running at that temp. It takes another 15-20 minutes to get to the 180.

TerrS

PS I live in PA. And we don't have a keepwarm site. And I messaged my gas company, but it seems they might only help low income household.. so I am still looking

hot_rod

Sorry, I had Chicago on my mind. You should be able to find an energy auditor, at the very least some one that does thermal scans
or get an IR adapter for your phone

So many to do’s on this challange

pedmec

its not about the amount of water. its about how much water you can move (gpm) with a 20 degree design average thru your baseboard.

But i'll play along. Riddle me this.

one gallon of water requires 8.33 btus to raise that water 1 degree. so now we start from room temperature boiler water, we will call it 70 degrees, and bringing it up to 180 degrees. 110 degree temperature rise.

gallons x weight/btus x delta t

13.8 x 8.33 x 110 = 12,645 btus (cold start)

boiler input 150,000 boiler output 113,000

113,000/60 = 1883 btu's/minute boiler output

12,645/1883= 6.7 minutes

6.7 minutes to heat boiler water from 70 degree to 180. That's just to heat the amount of water you claim in your system. that's what it takes to raise the temperature of all the water from a cold start. now when you reach 180 and you have 160 return you are adding even less to the boiler water.

13.8 x 8.33 x 20 = 2299 btus/minute

And this why the amount of water doesn't really matter in a baseboard system. Only when it comes to large radiator system does the amount of water matter. And for other reasons we can't discuss right now.



(btu output @ 110 degrees x amount of elements divided by 60 minutes= btu per foot/minute

150 btu' @ 110 degrees
(150 x 124)/60 = 310 btus per minute output from element

boiler output per minute

113000/60 = 1883 btu's per minute almost 5x the amount of heat into boiler than the element can reject into the house. water temperature has to rapidly increase due to left over btu's.

200 btu's@ 120 degree
(200 x 124)/60= 413 btu' s
1883-413= 1470 btu's remaining. stays in the water and increases temperature to boiler

250 btu's@ 130 degree
(250 x 124)/60= 516 btu's
1883-516= 1367 btu's remaining. Boiler temperature till increasing fast. you can't dissipate heat fast enough for boiler to not short cycle. i adjusted everything for minute so you can get an idea of whats happening and why the boiler temperature should not take 45 minutes to get to 180. Its like the train analogy. You just keep picking up passengers but rarely anyone's getting off.

I would, if possible, clock the meter. see if you are getting the correct output. Ill bet the the second valve in the reduntant gas valve is not opening. I had plenty of honeywell rv8400's failure on the second opening.

SuperTech

I've been following along. Obviously tightening the home up will always help but the next step should be to get a knowledgeable technician who is familiar with combustion analysis to check out the operation of the boiler.  Check draft, inlet and manifold gas pressure, combustion efficiency and delta T.

TerrS

@pedmec thank you not that I completely understand all that. But I agree something is seriously wrong. I just had my boiler serviced. 1 month ago after my new SS flue liner and my chimney was clogged I found.

I will attach 2 more pictures but I only have one gas valve. And 4 burners. I can tell you last year the times I quoted were true, I am not lying as I am looking for help!!  He did test the gas valve and it was like .2 something lower than he expected but within range is what he told me.

I have not turned on my boiler yet this year so I don't know if the boiler was starved for air or not, or how long it takes now, next week it's going to get colder in Pittsburgh.

psb75

TerrS, you are getting some fantastic information here. However, there are too many "moving targets" for folks to "zero in on." It's time that you get a live body standing on site and bringing together "the whole picture." It is frustrating for you, to get contractors on site and then having them tend to their specific tasks. And then leave. They are only dealing with one part of a problematic "whole." The infrared camera is a great suggestion, but even that is only a start. Its worth your time to identify a good knowledgeable person to come on site and map out a plan. Use this feature of the forum:

Click here to Find a Contractor in your area.

KC_Jones

By her description the pump is starting 2 minutes after the burner. She said it takes 30 minutes and the toe kick turns on, that means the pump is running, as far as I can tell. So it’s not the time to heat, it’s the time to heat the water while heating the house at the same time. The 30 minutes starts making more sense if that’s happening. It also shows a potential control problem I believe.

I thought it was supposed to get up to temperature, then start the pump. In that scenario the time to heat the boiler water would make sense.

If the pump is running at those low temperatures condensation could be a real concern.

TerrS

@psb75. No contractors found within 100 miles, so it's been a challenge to find people. And most are worth 0, they come in answer nothing. Say everything is fine and leave. It's just like the 3 new boiler bids. Can't answer any questions. Just spend $$$$$ and be happy. This is for everything I ask about boilers. Seems everyone only knows forced air!! 

psb75

You are in Pittsburgh. I'll bet there is at least ONE good "wet-head" in the area. Find that person! Yes, most of North America is still hooked on forced air. The "core" of this website is steam and hot water heat. Really good experts inhabit this site, but there is NOTHING better than "eyes and brain"....at YOUR site.

WMno57

@captainco do you know of anyone in Pittsburgh, PA that owns a combustion analyzer and knows how to use it?

pecmsg

Bayside Heating and Air Conditioning
22085 U.S. 19
Zelienople, Pennsylvania 16063

Pennwood Heating & Cooling
625 Macbeth Dr
Pittsburgh, PA 15235-4613

pecmsg

Options For Healthy Living
Fort Cherry Rd
McDonald, PA 15057

KMS Heating & Cooling
12490 Adams Drive
North Huntingdon, PA 15642

WMno57

As @SuperTech said, the next step is have a tech do five things. The tech must leave you a written report documenting these five things.

1. Check draft
   
2. inlet gas pressure
   
3. manifold gas pressure
   
4. combustion efficiency
   
5. delta T
   

pecmsg

https://www.myhomecomfort.org/find-a-contractor/

NoelAnderson

I don't know if it has been asked, but what is your system cold fill pressure? Since I see now you are heating an attic that would be three stories tall. Your initial cold fill pressure should be @ 18 PSI. and not the typical 12PSI. along with the air charge on the diaphragm expansion tank. If your fill pressure is not high enough you will not have any water circulation on the third floor attic.

psb75

She indicated that there is radiation on FOUR levels. And...three different kinds of radiation.

pedmec

I'm still sticking with my gas valve problem. Did he measure inlet gas pressure or did he measure manifold gas pressure. Big difference. If you ain't running with the design gas pressure your just simmering the water. And its not an uncommon problem. You don't realize it until the temperatures start to really drop outside. You should really try and get that info.

TerrS

@KC_Jones that 2min delay has only been introduced since adding the Beckett 7610. This helped only a little, it also runs the circulator after the t-stat is satisfied for 3 minutes because I was wasting spent energy in the boiler if it just got to 180 and the t-stat said I'm good, shut off. Again it's been this way forever, because as a homeowner I didn't know better. Now getting higher bills means I am taking a serious look at why and this thread has really shed light on potential issues.

@pecmsg thanks I will contact 2 of those clos

NoelAnderson said:

I don't know if it has been asked, but what is your system cold fill pressure? Since I see now you are heating an attic that would be three stories tall. Your initial cold fill pressure should be @ 18 PSI. and not the typical 12PSI. along with the air charge on the diaphragm expansion tank. If your fill pressure is not high enough you will not have any water circulation on the third floor attic.

Its at 20psi.

TerrS

pedmec said:

I'm still sticking with my gas valve problem. Did he measure inlet gas pressure or did he measure manifold gas pressure. Big difference. If you ain't running with the design gas pressure your just simmering the water. And its not an uncommon problem. You don't realize it until the temperatures start to really drop outside. You should really try and get that info.

All I can tell you. He took something off the valve and put some type of Guage that read and don't quote me here. But I think it was either 2.8 or 3.8.  He gave me no other printouts or information

KC_Jones

TerrS said:

@KC_Jones that 2min delay has only been introduced since adding the Beckett 7610. This helped only a little, it also runs the circulator after the t-stat is satisfied for 3 minutes because I was wasting spent energy in the boiler if it just got to 180 and the t-stat said I'm good, shut off. Again it's been this way forever, because as a homeowner I didn't know better. Now getting higher bills means I am taking a serious look at why and this thread has really shed light on potential issues.

@pecmsg thanks I will contact 2 of those clos

NoelAnderson said:

I don't know if it has been asked, but what is your system cold fill pressure? Since I see now you are heating an attic that would be three stories tall. Your initial cold fill pressure should be @ 18 PSI. and not the typical 12PSI. along with the air charge on the diaphragm expansion tank. If your fill pressure is not high enough you will not have any water circulation on the third floor attic.

Its at 20psi.



Just to be clear, you don't want the circulator running based on time, it should run based on water temperature, in your case that should be ~180° before the circulator turns on.

Everyone stating it should take 7 minutes to heat the water is assuming the circulator is not running until the water hits 180°, which is how it's supposed to work. If it's running long before it hits 180° that would definitely help explain the long time to get up to temperature because you are heating the house with that relatively low temperature water, basically shedding the BTU's that everyone is assuming are going into the boiler only.

That is unless I'm missing something in your description of operation.

pecmsg

For the record those contacts came from the HVAC-TALK Web site contractor locator.

TerrS

@KC_Jones

Just to be clear, you don't want the circulator running based on time, it should run based on water temperature, in your case that should be ~180° before the circulator turns on. Everyone stating it should take 7 minutes to heat the water is assuming the circulator is not running until the water hits 180°, which is how it's supposed to work. If it's running long before it hits 180° that would definitely help explain the long time to get up to temperature because you are heating the house with that relatively low temperature water, basically shedding the BTU's that everyone is assuming are going into the boiler only. That is unless I'm missing something in your description of operation.

There has never been that option on my boiler. Even with the old Honeywell l8124. T-stat calls for heat, circulator starts, then the boiler fires. For 30 years it's been that way and many service technicians later it's still basically that way.

When I had the Beckett installed we introduced those delays as to help. Remember boiler tank is only around 6 gallon. The systems zones make up the other 7.8 or so gallons.

So unless you can tell me how to change that or what to add, I can't even ask for it.

Again as a homeowner who has done some research is still very much lost.

pedmec

@KC_Jones The 7 minute was to point out that the volume of water in the system really doesn't matter. It takes barely any energy to raise the temperature of the existing water and that's from a cold start, which is really not whats going to happen. The boiler will be most likely warm on every heat demand if not hot. She stated that it took 30 minutes to go from a cold start to 120 degrees (@Terr, am i right on that?). Now with a time delay on the circulator it should raise the water in the boiler even faster as the water is not moving.

TerrS

@pedmec yes correct.  So I probably need to explain some more here. I stated it but didn't make it a point.

So I use a single programmable t-stat. From 5:30am to 9am I heat the house to 68 degrees. Then Everyone leaves for work, I set to 64, until 3pm -10pm it's back to 68. Then 10pm to 5:30am it's back to 64. Saturday and Sundays it's 68 degrees except from 10pm to 6am it back to 64.

This was because my bills and therm usage was even higher before this. So I will agree with you after the initial cold starts, and during those 68 degree time-frames the boiler probably doesn't start at 64 degrees like it's sitting at right now, if I was to turn on the boiler.

So following my logic two cold starts a day, unless it's really cold and my house drops lower than 64, the boiler doesn't fire. And following everyone's thoughts as to really how long it should take would make great sense. But taking 40 minutes gets lost in the logic.

And I need to find that explanation

neilc

TerrS said:

@KC_Jones that 2min delay has only been introduced since adding the Beckett 7610. This helped only a little, it also runs the circulator after the t-stat is satisfied for 3 minutes because I was wasting spent energy in the boiler if it just got to 180 and the t-stat said I'm good, shut off. Again it's been this way forever, because as a homeowner I didn't know better. Now getting higher bills means I am taking a serious look at why and this thread has really shed light on potential issues.

@pecmsg thanks I will contact 2 of those clos

NoelAnderson said:

I don't know if it has been asked, but what is your system cold fill pressure? Since I see now you are heating an attic that would be three stories tall. Your initial cold fill pressure should be @ 18 PSI. and not the typical 12PSI. along with the air charge on the diaphragm expansion tank. If your fill pressure is not high enough you will not have any water circulation on the third floor attic.

Its at 20psi.



can we revisit this a moment?
are you seeing 20 with the boiler on? circ running ?
can you shut it all off a minute and check that pressure again ?

hot_rod

The key piece of information is still missing, the heat loss of the individual rooms or zones and the total. Only with that could we determining how much heat emitter is required, operating temperature, pump size, required, etc, etc.

It seem regardless of when the circ starts, a boiler twice the size of the radiation should catch that load quickly, depending of course on the heat load at the time. Certainly in days under design, 80% of the year, it should be minutes to get up above condensing temperatures.

Either the boiler output is constipated, or the connected piping and emitters and load is much larger?.

Here is an example of the proper design sim, enter the room loads in BTU/ hr and to program shows required fin tube, operating condition, etc..

Isn't Ray Wolfarth in the Pittsburg area. Maybe he could help, or know a local knowledgable hydronics person.

WMno57

Ray's profile page:
https://forum.heatinghelp.com/profile/raywohlfarth
Ray's website:
https://fireiceheat.com/
Ray's contact information:
email: ray@fireiceheat.com
phone: 412.343.4110

TerrS

neilc said:

can we revisit this a moment? are you seeing 20 with the boiler on? circ running ? can you shut it all off a minute and check that pressure again ?

Cold boiler it's sits at 20. Hot boiler sits at 25, a relief valve pops at 30

TerrS

@hot_rod agree in maybe the short-term and maybe long-term.

But when you say my 124ft of emitters, have you considered that 300ft of exposed un insulated supply and return 3/4 pipe running throughout my house?

We still don't understand, maybe, if I am heating 13.8 gallons of water while it's trying to also heat the house takes 40 minutes. But I  think that is the crux of the why. It's not just big pot, with 150k btus under it. It's 6 gallons always getting refreshed, until finally the return water is within 10-15 degrees  of the supply water, then the boiler is in control and not playing catchup.

TerrS

WMno57 said:

Ray's profile page: https://forum.heatinghelp.com/profile/raywohlfarth Ray's website: https://fireiceheat.com/ Ray's contact information: email: ray@fireiceheat.com phone: 412.343.4110

Thanks just messaged him also

pedmec

The fill pressure won't matter. If you don't reach the top floor it just means you have less load on the boiler. you wont reach the top floor zone. That in turn will allow the boiler temperature to increase faster. I think we are forgetting the crux of her issue. Its the time (40 minutes on a baseboard system) it takes to heat the water from a cold start to 180 and why is does she need 180 to be comfortable.

I stand by what i said before until proven otherwise. Underfiring and not enough baseboard.

hot_rod

TerrS said:

@hot_rod agree in maybe the short-term and maybe long-term.

But when you say my 124ft of emitters, have you considered that 300ft of exposed un insulated supply and return 3/4 pipe running throughout my house?

We still don't understand, maybe, if I am heating 13.8 gallons of water while it's trying to also heat the house takes 40 minutes. But I  think that is the crux of the why. It's not just big pot, with 150k btus under it. It's 6 gallons always getting refreshed, until finally the return water is within 10-15 degrees  of the supply water, then the boiler is in control and not playing catchup.

If any uninsulated piping is inside the insulated structure, it is not heat loss, it is still adding to the space. So the structure needs to be as tight and insulated as possible. i'm assuming none of the piping is outside the home?

Don't get hung up on the gallons of water in the system or boiler. With 150,000 boiler of whatever the derate output is, that small volume of water will heat within a few minutes. Fresh cold water is not entering your system, so temperature rise should be instant when the burner turns on. 8.33 btu to raise 1 gallon of water 1°

So from 50F to 180F requires 1,082 BTU., Say 20 gallons total? Plug in whatever numbers you know. 20gallon X 1082= 21,658 btu. You have at least 113,000 btu to give. See the problem?

Either the boiler is only producing a fraction of its rated output, you don't have enough heat emitter to distribute that much, or some unexplainable combination of the above.
pipe size in basement looks adequate to move what the boiler produces.

If the heat emitters are inadequate, or the piping not able to move the 113,000 the boiler would race to the 180F setpoint.

Consider a gas fired, tank type water heater holding 50 gallons, it will heat from 50° - 140 in under 30 minutes with 30,000 btu burner, 1/5 the size of your boiler.

So the heat output issues are not at all related to how much water your system contains.

If you have open stairwells, remember heat will travel up and down those openings, going from the higher temperature to lower.

So the second floor at 64F and lower at 70F will cause some of that heat energy to travel up, and the cooler air upstairs to fall down.

You have plenty to digest, understanding thermal equilibrium my be too much right now, here is a graphic showing the relationship between what a heat source can provide and how the attached heat emitters control that heat source. A pic of high output baseboard.

TerrS

@pedmec totally agree! I thought we already sortof determined based on a few factors like total house envelope insulation, I am under size in emitters, and I have scoured the web looking for better emitter options but there really are none for my design.

Which means

1.  if I drop water temperature with the amount of fins currently, I freeze.

2. Installing more emitters is impossible as I have no more walls, plus getting supply lines to them, again might as well rip down the house.

3. Upgrade to all panel radiators, this actually gives off very similar heat but at lower water temperature. This comes at a major cost!

So then we have to ask, what are we trying to accomplish. Don't try and put me in that condensing 95% - 140 degree water boiler. It will never ever work in this current design. Unless we want to live in parkas!! 

So we have to live with how I can overcome some of the issues we know.

Why the lag in coming to temp, I have contacted 2 companies to come and see the issues like everyone suggested.

Eventually increase the homes insulation efficiency, as increasing emitters is more costly.

Lastly and I am still leaning, zone the upstairs because it's colder. Maybe because of design or maybe if just never gets to temperature because the thermostat is so far away. It has way more ft of fins, compared to the rest of the house, like 42ft in the 4 bedrooms and hallway and most rooms have been insulated and remodeling. Except for the ceilings in each room which is below the heated attic. So another areas to look at.