How to Plumb a Harman VF3000 Boiler

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Thu. Mar. 06, 2008 6:29 pm

Sting wrote:The only way to understand the difference between moving sufficient GPM [SUCCESSFULLY] is to read the books I have listed. We cannot go into the detail it will take here. I understand your doubt and please don't take offense at my persistence. Read the books and gently learn why.
I'm getting mad at you. :x I want to see a full size picture of the monster in your avatar. 8-)

Let's you and me go into detail, shall we? I challenge you and all the other board members to show me how this won't work. And if it won't, how you can make it work. We need to define a totally auto setup. You light the fire and walk away. When the coal boiler is up to temp, it takes over. When the coal boiler dies, gas/oil takes over. No valves to touch, no switches to throw. No temp switches, relays, interfacing control wiring. Just plug and play. And it minimizes losses.

I do not in any way doubt that this will work as I described it. I don't have time for reading any of your recommended books, that would cut into my time here.

While I am not a licensed Professional Engineer, I have been employed as the Chief Engineer for the Cintas Corporation's facility in Branford, CT for the last 15 years. I was not new at this when I got there either. I have over 80 pumps ranging from small fractional HP to twin 60 HP pumps running in loops and fed by twin 25's in a Ultrafilter of my own design. In my tenure here, I have processed, reused, cleaned and sanitized over 150 million gallons of wastewater.

This design will flow water exactly as the gas boiler sees it now, if you don't believe it please describe how it fails. If it won't work at the flow rate now, it will not satisfy the demand if the gas boiler was removed and installed in it's place exactly as shown in his drawing. Your asssumption of demand is correct if all four zones call for heat continuously. If that were the case, do you really think that beer keg size gas boiler could keep up with the same demand? When his house calls for heat from one zone, that zone pumps at the pump's rating through a 3/4" pipe, when it calls for heat from four zones, it pumps the same volume of water through four 3/4" pipes at the pump's rating. If the flow rate is the same, you are moving the same mass of heat. If I pump 200 gallons a minute through a three inch pipe, and I pump 200 gallons a minute through a six inch pipe, how much water comes out of each in a minute? I say it will keep up and it will do a better job heating the house than if it stood alone as it has almost twice the mass of heated water. How does the heat loss figure in here?

The ancient Greeks purposely tipped the Parthenon's roof supporting columns to lean inward so that when you stood at the base it would not appear to be falling down on top of you. While not a great engineering principle or making the strongest support, it is truly a magnificent building. You might also note that it is in fact about 2,500-3,000 years old. Sometimes you just don't need perfect.

So I'm calling bull crap on the pipe size. Prove me wrong. And bring a big picture of that traction engine. :)
Last edited by coaledsweat on Thu. Mar. 06, 2008 8:39 pm, edited 1 time in total.


 
User avatar
Scottscoaled
Member
Posts: 2812
Joined: Tue. Jan. 08, 2008 9:51 pm
Location: Malta N.Y.
Stoker Coal Boiler: EFM 520, 700, Van Wert 800 GJ 61,53
Baseburners & Antiques: Magic Stewart 16, times 2!
Coal Size/Type: Lots of buck
Other Heating: Slant Fin electric boiler backup

Post by Scottscoaled » Thu. Mar. 06, 2008 8:09 pm

Coaledsweat!! That last post was particularly powerful stuff! I agree with your method as that is the way mine is hooked up. It's outside also. But all things being even with the different ways of piping ,and there are many more than the few just argued, would't the system that has the additional pump be at a disadvantage simply for the additional 8 - 10 dollars in electricity it consumed every month? That's almost a ton of coal. The 3/4" pipe will flow the same as the 1 1/4" as you stated. Scott

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Thu. Mar. 06, 2008 8:39 pm

stokerscot wrote:Coaledsweat!! That last post was particularly powerful stuff! I agree with your method as that is the way mine is hooked up. It's outside also. But all things being even with the different ways of piping ,and there are many more than the few just argued, would't the system that has the additional pump be at a disadvantage simply for the additional 8 - 10 dollars in electricity it consumed every month? That's almost a ton of coal. The 3/4" pipe will flow the same as the 1 1/4" as you stated. Scott
I'm not sure how much juice it will use, but the circulator will last just about forever running continuously. It may consume a little more juice, but what is a totally auto system worth? It can't be an oppressive amount of money to run continuously as homes with modulating heating systems have pumps that run all the time. A lot of coal gasification boilers have hot to cold side return loop and a nightmare of valves and other devices to temper the incoming cold water return so the temperature isn't rapidly reduced and effect the gasification process. Some of these contraptions and heat storage systems run two or more pumps all the time. So I don't think the pump always running is a big deal.
One thing about this setup, I would think the coal boiler would run flatter because of the additional water volume. In other words, the high and low operating temperatures would be further apart in time. That in itself may save you more than the cost of running the pump in the first place. Matching firing rate to load demand is the most economical way to operate a boiler.
No one has brought this up so I will. The only place I can see how this wouldn't work is if the return water went to the gas boiler instead of the coal boiler. I can't see how that could happen as the gas boiler is under pressure from the coal boilers pump. When the zone valve opens and the pump starts,the hot water is pushed through the heating loop. Once it passes the zone circulator it will turn to the coal boiler as the gas boiler is already under pressure. It has to if it is going to satisfy it's circulator's suction demand. Yes/no?

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Thu. Mar. 06, 2008 9:55 pm

Instead - lets just go drinking! This threading pipe stuff is only bound to bring out the band aids. Dead guy I learned wet work from used to tell me " You need to leave a little blood on every job!"

I would rather leave it on a shape fitting than disrupt you folks more :|

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Thu. Mar. 06, 2008 10:10 pm

A TACO 007 pump cost as much to run as an 80 watt light bulb. Just thought of that. :oops:

At $.13 cents a Kilowatt its $.25 a day. I believe the coal savings will match or better that.

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Thu. Mar. 06, 2008 10:12 pm

Sting wrote: Dead guy I learned wet work from used to tell me " You need to leave a little blood on every job!"
What happened to him? Did he leave a little too much blood on the job one day?

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Thu. Mar. 06, 2008 10:19 pm

hummmm

That doesn't sound pleasant or friendly.

I was told this was a friendly place.

:!:


 
User avatar
coalkirk
Member
Posts: 5185
Joined: Wed. May. 17, 2006 8:12 pm
Location: Forest Hill MD
Stoker Coal Boiler: 1981 EFM DF520 retired
Hand Fed Coal Stove: Jotul 507 on standby
Coal Size/Type: Lehigh anthracite/rice coal

Post by coalkirk » Thu. Mar. 06, 2008 11:23 pm

I'm not sure why you keep referring to the boilers pressure relief valve?? I'm sure it's 3/4". What difference does that make? It only comes into play if the boiler overheats or the pressure exceeds 30 psi. It has nothing to do with the amount of hot water being supplied to the gas boiler from the coal boiler or the heat loss to the zones. I'm not trying to be confrontational, I'm really trying to learn and understand. What is your concern with the pressure relief valve size?

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Fri. Mar. 07, 2008 7:27 am

coalkirk wrote:I'm not sure why you keep referring to the boilers pressure relief valve?? I'm sure it's 3/4". What difference does that make? It only comes into play if the boiler overheats or the pressure exceeds 30 psi. It has nothing to do with the amount of hot water being supplied to the gas boiler from the coal boiler or the heat loss to the zones. I'm not trying to be confrontational, I'm really trying to learn and understand. What is your concern with the pressure relief valve size?
My concern is not with the valve, but where it screws into the boiler. Most boilers always have reducing bushings installed in their threaded connections with the exception of the cold retun. My boiler has a 3/4" NPT PRV and the port it is in is bushed down from 1 1/4" NPT. Earlier in the thread there was mention of concern that a 3/4" pipe could not handle the heating demand. Since the flow design's we are discussing relies on the use of a second port at the top of the boiler, I would like to allieviate any concerns about that isssue (the inlet pipe size at the PRV). Most are bushed down and would be able to handle sizes larger than 3/4" NPT. I don't believe the pipe size would have any impact on the systems performance, some people have expessed concern.
Last edited by coaledsweat on Fri. Mar. 07, 2008 11:35 am, edited 1 time in total.

 
User avatar
Adamiscold
Member
Posts: 1116
Joined: Fri. Feb. 29, 2008 7:09 am
Location: Winchendon,Ma

Post by Adamiscold » Fri. Mar. 07, 2008 8:08 am

This may not have anything to do with your setup but I'll throw it out there to see if it helps a little bit. On my system I have my hot water flowing through a 1 1/4 inch pipe in the beginning of my manifold then it splits off into three separate zones with 3/4 inch pipe. By having the 1 1/4 pipe it allows me to have more heated water that can be more evenly displaced through each zone, it is not to increase the gpm. As long as there is no air in your system and you are not taking water away from your system then water pressure and gpm should not be effected. On my system if I have the pumps running and there is a call for water in the house somewhere (faucets, tub) then water pressure will drop a little because my system is now open, but the gpm doesn't change because the hot water that's being called to the house is made up by adding cold water to the heating system. Hence it's cooling off the heating system.

I have three variable pumps on my system which are used to adjust the returning heat temperature for each zone, unless you are trying to adjust the temperature I don't see why you would need an adjustable pump? When we first setup our system we were concern with the added cost of electricity for the running of the pumps but over the last three mouths our electric bill has gone down and it never spiked up with having the pumps running since they where turned on in November. I know my house needs a lot more attic insulation which we will address this summer, so this winter we have used a lot more oil and a lot more of the pumps then we would have if the house was better insulated.

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Mar. 07, 2008 8:33 am

You fellows keep banging your head into the same ports on these boilers - now for what 2 - 3 pages - obviously I have hit a nerve. I don't need challenges and I hate to make enemies but I just reread coalkirks signature and I also enjoy Churchill's quotes.

So read the books

Tell me when your finished

There will be a quizz following

variable speed pumps - manual blending valves - correct size piping - are all installed to enhance system performance - You can heat the bathroom with a couple of candles if that is enough to keep the dumper from freezing. There is no right and wrong - mostly - but there is better!

 
User avatar
coalkirk
Member
Posts: 5185
Joined: Wed. May. 17, 2006 8:12 pm
Location: Forest Hill MD
Stoker Coal Boiler: 1981 EFM DF520 retired
Hand Fed Coal Stove: Jotul 507 on standby
Coal Size/Type: Lehigh anthracite/rice coal

Post by coalkirk » Fri. Mar. 07, 2008 8:43 am

coaledsweat wrote:
coalkirk wrote:I'm not sure why you keep referring to the boilers pressure relief valve?? I'm sure it's 3/4". What difference does that make? It only comes into play if the boiler overheats or the pressure exceeds 30 psi. It has nothing to do with the amount of hot water being supplied to the gas boiler from the coal boiler or the heat loss to the zones. I'm not trying to be confrontational, I'm really trying to learn and understand. What is your concern with the pressure relief valve size?
My concern is not with the valve, but where it screws into the boiler. Most boilers always have reducing bushings installed in their threaded connections with the exception of the cold retun. My boiler has a 3/4" NPT PRV and the port it is bushed down from 1 1/4" NPT. Earlier in the thread there was mention of concern that a 3/4" pipe could not handle the heating demand. Since the flow design's we are discussing relies on the use of a second port at the top of the boiler, I would like to allieviate any concerns about that isssue (the inlet pipe size at the PRV). Most are bushed down and would be able to handle sizes larger than 3/4" NPT. I don't believe the pipe size would have any impact on the systems performance, some people have expessed concern.
Sorry, I'm still not following your point. Agreed, the PRV is 3/4". Most boilers this port is actually 3/4", not 1 1/4" with reducing bushing. It also should not be removed, altered or its port used for anything else. The feed from the coal boiler should go into the return manifold of the gas boiler (1 1/4") and the water from the gas boiler back to the return of the coal boiler should come off of the supply manifold of the gas boiler (1 1/4") The PRV does not change, get moved or it's port used or shared by anything else.

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Fri. Mar. 07, 2008 9:33 am

While I admire your strict adherance to engineering principles and agree that what you describe will work, I have two problems with it. One is the coal circulator will have to run continuously whether you are heating with coal or gas. When you are heating with gas you will be circulating water to the coal boiler to keep its mass up to temperature. In doing so, you will have a continuous heat loss up the chimney. Both of these scenarios are efficiency losses. If I am wrong, please explain what I am missing here.

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Fri. Mar. 07, 2008 9:36 am

coalkirk wrote:I'm not sure why you keep referring to the boilers pressure relief valve?? I'm sure it's 3/4". What difference does that make? It only comes into play if the boiler overheats or the pressure exceeds 30 psi.
A PRV will not go off on temperature, only pressure. The temperature listed on it is its safe operating limit, not a relief point.

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Mar. 07, 2008 10:06 am

coaledsweat wrote:While I admire your strict adherance to engineering principles and agree that what you describe will work, I have two problems with it. One is the coal circulator will have to run continuously whether you are heating with coal or gas. When you are heating with gas you will be circulating water to the coal boiler to keep its mass up to temperature. In doing so, you will have a continuous heat loss up the chimney. Both of these scenarios are efficiency losses. If I am wrong, please explain what I am missing here.
http://www.houseneeds.com/shop/heatingproducts/he ... ermain.asp

Add as many boilers as you like to this design - just put the close spaced Tees of each boiler 18 inches apart on piping of same size as the largest (supply/return) port of any one of the boilers in the team.
operate them alone or in any sequence of team you want or need to heat the load - a Teckmar multi boiler control can do that the best.
Only the pumps you want to run will - there is no heat loss up the chimney of the cold boiler and boilers not running will not be heated by its team member to cause a loss- only the return leg of the current house system needs to be opened to install - there is no loss, only gains because each boiler can be balanced to run at correct delta T without the issues of series looping them together -

I have told you several times - the explanation to ALL you doubts and questions is documented in the literature I posted - sorry you have to buy it - my books found new homes by folks that forgot to return them long ago or I would send you mine.

If you still wish to "challenge me" or make me prove to you how and why - there I have - read


Post Reply

Return to “Stoker Coal Boilers Using Anthracite (Hydronic & Steam)”