plumbing coal boiler to oil boiler

plumbing coal boiler to oil boiler

PostBy: wilder11354 On: Tue Jul 19, 2011 9:49 pm

going to be getting coal boiler in another week (handfired). Going to do some replumbing of exsisting oil boiler(new watts AS-MB 1 1/4" seperator,watts B911 combo fill/BF valve,watts RBFF ResBoilFill Fitting) reposition the exspansion tank off the top of boiler to seperator unit where it should be, and put a pressure gage just above exspansion tank between it and the RBFF valve.

i am going to put duplicate setup on the coal boiler for water supply,backflow and airtrap/expansion. the 2 units will be in seperate parts of house, looking for a pump to run at a low speed continually to keep water circulating between the 2 units to maintain constant temp, and when there is a demand for heat to run pump at a higher GPM flow.

Zones are individual taco pumps, honeywell R845A controlled, zone calls for heat it turns on pump, and draws off common manifold for supply side off boiler, return from zone go to common return manifold then to boiler.
So my hooking up to exsisiting boiler will be rather easy using the common manifolds, and some valves, and "T" and 90's fittings in return/supply side feeds before commonon manifolds.

question is????.....is the duplication of cold feed,exspansion stuff appropiate? and who knows of a pump with a continual low flow/speed variable motor and what contoller to use for the 4 inputs from taco pump controllers?

Coal boiler will still be independent of oil furnce controls for its aquastat/draft controls.
wilder11354
 
Hand Fed Coal Boiler: Harman SF260
Coal Size/Type: nut or pea, anthracite
Other Heating: crown oil boiler, backup.if needed

Re: plumbing coal boiler to oil boiler

PostBy: Rob R. On: Tue Jul 19, 2011 10:03 pm

Handfired!? I thought you were "sold" on a Keystoker?

In any case, I don't understand why you want to duplicate the fill valve, BPV, etc? Connect the two boilers however you want, and increase the expansion capacity as needed. Unless you intend to run the coal boiler "valved off" from the oil unit, I see no need for the redundancy.

How far apart are the two boilers? How much heat do you need to move? Taco makes circulators that ramp up or down based on delta T or a temperature setpoint.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Coal Size/Type: Rice/buck
Other Heating: Dad's 1953 EFM Highboy

Re: plumbing coal boiler to oil boiler

PostBy: wilder11354 On: Tue Jul 19, 2011 10:22 pm

there going to be about 25 feet horizontally, but connecting plumbing will go underneath structures, and back up to each unit. still going to redo exsisting boiler setup, water is hard on components, have corrosion issues with some parts now, and there 6 years old. But seperate fill/BF/exspansion appeals to me because if oil unit furnance box itself needs to be isolated while in service coal unit will still operate fine. Oh yea there will be a dunp zone added on to this, for the oh what the heck type stuff.

Cost between hand fired and stoker units are quite a bit. And i don't mind doing what it takes to feed, besides still have to do the ash pan check daily.
wilder11354
 
Hand Fed Coal Boiler: Harman SF260
Coal Size/Type: nut or pea, anthracite
Other Heating: crown oil boiler, backup.if needed


Re: plumbing coal boiler to oil boiler

PostBy: Sting On: Tue Jul 19, 2011 10:46 pm

You can add as much or as little redundancy to the system as you wish

There is no correct answer for this except "IT DEPENDS!"
Sting
 
Other Heating: BurnHAM=NG-gas

Re: plumbing coal boiler to oil boiler

PostBy: Freddy On: Wed Jul 20, 2011 7:22 am

Sounds like you have things under control. Just get 'er done!
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: plumbing coal boiler to oil boiler

PostBy: steamup On: Wed Jul 20, 2011 7:52 am

Cross connecting two independent systems, each with expansion and fill points will create the potential for a lot of pressure fluctuation problems.

One fill and expansion point for the system, or separate the two systems with a plate and frame heat exchanger.

Connecting two boilers remote from each other must be done carefully.
steamup
 
Stoker Coal Boiler: Axeman-Anderson AA-130, Keystoker K-6
Hand Fed Coal Boiler: HS Tarm 502 Wood/Coal/Oil
Coal Size/Type: pea, buck, rice

Re: plumbing coal boiler to oil boiler

PostBy: wilder11354 On: Wed Jul 20, 2011 9:43 pm

i don't see where pressure fluctuation will be a problem it both fill/regulator/BF valves are set at same pressure settings, and exspansion tanks set same pressure. boilers will be on same horizontal level to each other, Still using same domestic cold feed supply for each, both will be feed by same size feed lines. system should be balanced. Yes there will be possible pressure bleed off in E tanks but can easily isolate and check them with the RBBF valve, or the pressure regulator setting same way, without shutting down entire system.

Just worry about getting correst flow rate on pump interconnecting the 2 units, compared to the individual zone pump flow rates when on demand. want an equa tl or slightly higher flow rate for connector pump when demand is called for compared to individual zone pumps flow on demand. yes theres (head) pressure in system but still pumps create a suction when on and if interconnect pump isn't flow equal to or greater then suction it will be like a restrictor orfice being in the line.

lets see, 4 zone pumps.. wil be more suction applied than one, 2 or 3. I got some figuring to do, and system(pump) contol/pump products to read a bit more about.
wilder11354
 
Hand Fed Coal Boiler: Harman SF260
Coal Size/Type: nut or pea, anthracite
Other Heating: crown oil boiler, backup.if needed

Re: plumbing coal boiler to oil boiler

PostBy: Sting On: Wed Jul 20, 2011 11:30 pm

wilder11354 wrote:i don't see where pressure fluctuation will be a problem it both fill/regulator/BF valves are set at same pressure settings,


and there lies the real issue here


wilder11354 wrote:correst flow rate


corectus -- ???? Humungus


wilder11354 wrote:I got some figuring to do, and system(pump) contol/pump products to read a bit more about.


start with a book on primary-secondary piping in heating systems - or simply use the fine search engine on this web site for detailed spewing from folks who already took the arrows in their back -- you know the pioneers - the old dead plumbers assistants or simple wannabeeeeeeeee's

:roll:
Sting
 
Other Heating: BurnHAM=NG-gas

Re: plumbing coal boiler to oil boiler

PostBy: blrman07 On: Thu Jul 21, 2011 7:18 am

From a boiler inspector and operator you do not need to have a fill valve with a bfp, and expansion tank on each boiler. The boilers do not need to be next to each other to function properly but it helps. You DO need to have a circ pump large enough to handle flow to both boilers at the same time, a makeup line large enough to handle both boilers, and one expansion tank large enough for the entire system. When you start making systems with multiple boilers, the function of the system becomes the most important part, not the individual boiler. With the boilers separated from each other you may need to throttle valves to balance out the flow to and from each boiler.
blrman07
 
Hand Fed Coal Boiler: Bucket a Day
Hot Air Coal Stoker Furnace: Leisure Line Econo 1 stove
Coal Size/Type: Rice in the LL and anything that will fit in the Bucket a Day. It's not fussy.

Re: plumbing coal boiler to oil boiler

PostBy: wilder11354 On: Thu Aug 04, 2011 8:22 pm

I will be using a Taco VS Delta T 0012 circulator pump between the 2 boilers for circulating the water between them. 1; it will have a hgher GPM flow then the 007 pumps that control individual zones in system now (when they run) 2; the speed will be controlled by return/feed side pipes temp differential between 2 boilers and when the demand for heat is called from individual zone thermostats.


Taco 0012-VDTF3
wilder11354
 
Hand Fed Coal Boiler: Harman SF260
Coal Size/Type: nut or pea, anthracite
Other Heating: crown oil boiler, backup.if needed