VF 3000 Distribution Timer

I also took advantage of this unused timer by useing it to power a small pinball machine fan to extend my off time and a more complete burn of coal before it goes to the ash pan.I rigged this up for summer DHW and am useing it now with a better burn.The ash tells the story on the warmer days already.While the small fan is blowing there are very small blue flames dancing above the coals on the stoker off time thus making useable BTU's rather than unburnt and half burnt coal being pushed front to never be ignited.Here is the crude set up as I will need to make a decent installation after more testing on hot summer days.Keystoker thought of this with their small fan.

Fun project! Thanks for sharing.

Neat! Very creative!

How does it work when the full blower comes on?

Couldn't that small fan be a bottle neck for the full sized blower since you've hooked it into it's air inlet?

I'm just thinking outloud.

Beatle
Both fans run together while stokeing with the restrictor plate wide open.When the water temp is satisfied and the boiler goes to idle the small auxiliary fan [ controlled by the distribution timer ] will continue to run for 13 minutes.The air blows through the main stoker fan squirrel cage and goes under the hot coals just enough to keep small blue flames.

I gained a half of a point of draft during idle that will be welcomed in hot summertime as I have a short chimney.

I will be able to extend my off time as much as 9 minutes during summer operation.I can squeeze more BTU's out of all the coal before it gets pushed away from the burn zone. I see a difference in the ash pan.

Downside is the little fan will use a bit more electric.But I hate seeing black in my ashes.

hey stevey thanks for sharing, I thought about doing what you did , I agree when the VF3000 idles you end up with alot of partially burnt coal and adding another fan or as some have done is put a dimmer in line with the blower when it is in off mode and setting the dimmer for a slow speed will burn to coal better.... but I think you will end up just blowing the extra heat up the chimney .
I was going to burn coal all summer for DHW but since I see how Idle mode dosen't fully burn the coal and fuel oil is $1.50/gal
(cash) I will be switching over to OIL in another week or two. Then I won't have to deal with over temp dumping.

a good test to see if you gain anything would be to watch how many times your VF3000 goes into over temp with the extra fan and then without the extra fan running.

Hi Sync,was wondering how your doing.

I considerd the dimmer to operate the combustion fan on the off time but didn't want to buy the controls as I had the fan sitting around and the Harman timer was already in place.

My boiler went on line September 1'st last year and I made DHW for two months with a very small fire and never even came close to an overheat,the temps held at 150 to 160 with a two inch fire on the grate.Still had 80 plus degree days in there too.
The only overheat I have had yet was deliberate and artificialy created by swinging the A350 control to a lower setting to run the dump zone circulator and the Modine once and awhile.I adjust my feed rate often as outside temps dictate.

as far as useing the oil in summer,I worry about condensation and corrosion developing with the oil gun only fireing only two or three times a day to maintain DHW in a boiler that was useing coal in the winter.No matter how clean you get the unit I think it will draw moisture from coal usage.

Sure some extra heat created from the small auxiliary fan will go up the chimney but some of it has to go to maintaining or increasing the water temp a bit as it goes through the boiler chest to exit.