question about hooking up a VF 3000 boiler

question about hooking up a VF 3000 boiler

PostBy: syncmaster On: Wed May 07, 2008 10:58 pm

I will be ordering a VF3000 boiler.
This is how I think I should hook it up.
I have a 2400sqft ranch , weil mclain oil hot water P68 boiler with 5 zone valves, 30 gal superstore indirect hot water heater,

I think I should buy another taco007 cirulator pump mount it to the VF3000 and circulate the water between the Vf3000 and the P68 boiler.
set the aquastat on the P68 to 170* and the aqua stat on the VF3000 to 190* and let the new taco007 run 24/7

the P68 will handle all the calls for heat (5 zones) just like it did before.

I read someplace that when there is a call for heat you want to start the stoker rather than allow the vf3000 water temp to drop and the vf3000 aquastat to start the stoker.

Can someone clarify how to get the stoker stoking earlier?

Also, in the owners manual on the aquastat wiring layout (page21) it says "24v ac to overheat circulator or Zone valve"
OR 120v ac to overheat circulating pump. What does that mean?
It sounds like I need a run of baseboard to dump excess heat.... is this a safety to keep the water from boiling?


Thanks for your help.

Sync
Last edited by syncmaster on Thu May 08, 2008 4:15 am, edited 1 time in total.
syncmaster
 
Stoker Coal Boiler: harmanVF3000 Coal/oil option
Coal Size/Type: Rice
Stove/Furnace Make: VF3000
Stove/Furnace Model: Harman VF3000

Re: question about hooking up a VF 3000 boiler

PostBy: LsFarm On: Thu May 08, 2008 1:28 am

I don't see any problem with plumbing it the way you describe,, but you will loose some heat up the flue of the oil boiler, unless you have an electrlcly closing damper in the flue.. the heat from the warm boiler will heat the flue and chimney, creating a draft, and pulling heat out of the boiler..

The temp of the oil boiler should be set lower,, more like 150*... You want your oil boiler to only kick on if the coal boiler is out of service.. a coal boiler can take 10+ minutes to ramp up to a full fire... if it has burnt back to low idle,, the fire is very small, and if the house zones all call for heat at once,, the water temp WILL drop alot.. so if you are trying to eliminate oil use,, you may have some lag in the heating response of the coal boiler,, but at least you won't be burning oil.

I have my propane boiler set at 150*, just warm enough to keep the house at around 55-60*, if something happens to the coal boiler.. I can always turn it up.

Greg L
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: question about hooking up a VF 3000 boiler

PostBy: coalkirk On: Thu May 08, 2008 7:46 am

The way you are planning to plumb it is fine. That's how I installed mine. Once you are comfortable with the VF3K, you will probably just want to turn the oil burner off entirely. I'm heating 4,000 sq. ft. with my boiler and didn't burn a drop of oil this past season. Greg is right about the heat loss up the oil burner chimney. I disconnected a burner control wire so that my oil burner couldn't possibly fire and disconnected the flue pipe from the oil boiler to eliminate this problem.
Also, the first year I ran the VF3K, I kept the water at 180 just like the oil burner was. You burn alot of coal doing that. I think you will find it does the job with a lower water temperature and you'll burn less coal. I'd start out at 160 and see how it does.
The dump zone control is just what you thought. I'll admit I've never hooked mine up. Never had a need for it so far.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

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Re: question about hooking up a VF 3000 boiler

PostBy: coaledsweat On: Thu May 08, 2008 9:31 am

A stack damper will stop most of the heat loss from the oil burner. Keep in mind, the heat loss discussed is already present with the oil burner as is (if there is no stack damper), so switching to coal will be a huge savings whether that is addressed or not.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: question about hooking up a VF 3000 boiler

PostBy: Coalbrokdale On: Fri May 09, 2008 7:56 am

The dump valve is a good idea. The leads coming out of the control box are 110 volts, so if you pick up a 24 volt transformer then you can wire the 24 volt output to 1 of your zone valves which should also have a lead running to the cir pump relay. What this does is opens the zone valve and flips the relay to automaticly turn on the circ pump.

You can also adjust the "off-set" in the control box to allow the boiler to over shoot the set temp by a certain amount before dumping heat. This comes in handy in warm weather when just idiling in pilot mode before a call for DHW. I would not run extra baseboard for a dump zone, just use an existing zone.
Coalbrokdale
 
Stove/Furnace Make: Harman \ Coalbrookdale
Stove/Furnace Model: VF3000 \Darby

Re: question about hooking up a VF 3000 boiler

PostBy: syncmaster On: Fri May 09, 2008 8:52 am

Coalbrokdale wrote: I would not run extra baseboard for a dump zone, just use an existing zone.


If you dump to a zone in the house and it is summer and you have the central AC on it could be costly energy wise.

my boiler room is insulated and no AC so I might have to put in some baseboard in there and let it dump the heat there.
I will have to circulate fresh air from outside using 6" ducts and a small fan.

OR do you think this Overtemp doesen't happen in the summer?
syncmaster
 
Stoker Coal Boiler: harmanVF3000 Coal/oil option
Coal Size/Type: Rice
Stove/Furnace Make: VF3000
Stove/Furnace Model: Harman VF3000

Re: question about hooking up a VF 3000 boiler

PostBy: coalkirk On: Fri May 09, 2008 9:01 am

Probably more likely to happen in summer with low demand.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

Re: question about hooking up a VF 3000 boiler

PostBy: Freddy On: Fri May 09, 2008 9:38 am

Back up and run over me again? If everything is working properly, why would I need a dump zone? I thought they were only for solar panels. You can't shut the sun off and sometimes things will overheat. Other than that, I see no reason for a heat dump zone.....unless there's something I don't know (which is real possible! LOL)
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: question about hooking up a VF 3000 boiler

PostBy: syncmaster On: Fri May 09, 2008 10:09 am

Freddy wrote:Back up and run over me again? If everything is working properly, why would I need a dump zone? I thought they were only for solar panels. You can't shut the sun off and sometimes things will overheat. Other than that, I see no reason for a heat dump zone.....unless there's something I don't know (which is real possible! LOL)


Yes, Just like you can't shut the sun off, you can't shut the burning coal off either so the max temp is going to over shoot your max setting and you might want to dump the extra heat someplace.
you'll see there is a control on the VF3000 that puts out 24v and 110v to energize what ever you have hooked up to dump the extra heat.

I also have a hot water solar system, 2- 4x10 flat plate collectors and 120 gal tank. But I set mine up as a drain down system
when the max temp is reached (150*) the pump shuts off and all the water in the collectors drains back down into a tank.
The collectors are now dry and heat up to about 275* and at that point they are heat radiators. The excessive heat dosen't hurt them.
But if you allow the hot water tank to exceed 150* it will stress the welds and it will have a shorter life span.
since that solar tank costs over $1000.00 that short life would be very costly.

I would expect the same holds true for the welds in the VF3000, it probly shouldn't be allowed to get too hot if you want it to have a long life.
syncmaster
 
Stoker Coal Boiler: harmanVF3000 Coal/oil option
Coal Size/Type: Rice
Stove/Furnace Make: VF3000
Stove/Furnace Model: Harman VF3000

Re: question about hooking up a VF 3000 boiler

PostBy: coalkirk On: Fri May 09, 2008 10:11 am

You can't shut off coal either, unless you put it out. It is much easier to control than a wood boiler and lends itself to idleling much better than a wood boiler, but in times of low demand you can exceed your set point. I never have a problem with that because I keep my boiler temperature much lower than most, generally around 140 degrees. I also have a constant demand because of the way i use my boiler. It would be wize for most boiler users to hookupthe dump zone.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

Re: question about hooking up a VF 3000 boiler

PostBy: Richard S. On: Fri May 09, 2008 10:26 am

Overshhoots are common in the spring/fall and can actually cause the furnace to go out unless the timer is set to run regardless of temperature. What will happen is the nighttime temps drop, you'll get demand for heat sometime in the early morning and it has to stoke for quite a long time to get up to temp, the demand for heat will end but by that time you have raging inferno.... In the meantime it heats up outside and no more calls for heat and it will sit there for hours not running because the water temp is so high.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: question about hooking up a VF 3000 boiler

PostBy: Freddy On: Fri May 09, 2008 11:08 am

"Yes, Just like you can't shut the sun off, you can't shut the burning coal off either so the max temp is going to over shoot your max setting and you might want to dump the extra heat someplace."

Doesn't the aquastat stop the call for heat when the boiler reaches set point? Like... the boiler is at 140, you get a call for heat, it stokes until either A: the heat call is satisfied, or B: the boiler reaches set point. At either point, stoking stops. You're saying that now there is so much coal burning it will go over 220 degrees and blow off the pressure reflief if not for a dump zone? If there's enough coal in there left to burn that it'll go from 180 to over 220, how come it doesn't happen all winter?

Let's have a survey. How many of you have dump zones on your coal boilers?
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: question about hooking up a VF 3000 boiler

PostBy: Sting On: Fri May 09, 2008 11:21 am

Freddy wrote: Let's have a survey. How many of you have dump zones on your coal boilers?


Maybe this should be in another topic

but Ill play

I have a two stage over temp dump - with at tattle tale so if it launches when I am not around I can keep informed. It has only been used once and that was operator error issues! :cry:
Sting
 
Other Heating: BurnHAM=NG-gas

Re: question about hooking up a VF 3000 boiler

PostBy: coaledsweat On: Fri May 09, 2008 11:28 am

It doesn't happen in winter because there is always some demand for heat even if infrequently. A gas/oil unit will not fire above its max setpoint, a solid fuel appliance will always make heat if it is still burning, even if the Aquastat is satisfied. The solid fuel device has a minimum firing rate to keep the fire going (usally a timer on stokers, draft settings on hand fireds), oil/gas units just shut down until demand is renewed, a solid fuel device can't do that............ yet.

I am still running my hand fired boiler with highs in the 70s and lows in the 40s. Even with the draft closed way down, it is not uncommon to find the boiler at 200-220*. No, I never wired a dump zone for it, it just stores the heat until evening and after the boilers temp returns to normal, I open the draft before bed a little bit for the increased heat demand.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: question about hooking up a VF 3000 boiler

PostBy: Richard S. On: Fri May 09, 2008 11:39 am

Freddy wrote: If there's enough coal in there left to burn that it'll go from 180 to over 220, how come it doesn't happen all winter?


Ours is set for 160 hi in the summer, and yes there is enough to shoot it up to 220. I've seen ours hovering in that range at times even in the winter. Generally though when you get this large overshhoot the boiler has been idling along since the morning before. Then all at once it gets a very large demand for heat, then nothing afterwards. For example if you have an electronic thermostat that has different setting for the day... It gets to 6 in the morning and all of sudden it has to heat up the whole house 10 or 15 degrees from a very low water temp point. You'll make more than enough heat long before either the house gets warm enough or you hit the aquastat limit.

It doesn't happen in the winter or the summer (at least not for me) because you have a steady demand for heat. The furnace is going to run (or not run in the summer) in very consistent manner.

FYI we don't dump it at our house because this has never been a problem here. However at my Grandmother's who has a much smaller house with a boiler much larger than it needs to be its a problem. Same thing with another house next door, try explaining to the tenant that you want them to use as much free hot water as they can between 8 and 10 in the early morning. :lol: Typically it might go out one or two times a year.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

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