VF3000 Coil Question

Hello all. About 1 month ago I had my VF3000 delivered. This past weekend we moved it into my house. I plan on making another thread on that, but it was a bear.
Anyway, I have it in the basement, all level and ready to go. I am going to be tapping into my existing oil boiler piping. There are no shut off valves, so I spent the night draining the system.
When I purchased the VF3000 boiler (back in May), I didn't go for the coil option. I figured that it wouldn't be worth my money at the time. Fast forward a few months, and I am in my basement figuring out the piping down in my basement, and I realize that there is a DHW coil in our existing Crown oil boiler. I was surprised to find that. From that point on I was thinking of ways to plumb both boilers so I could use the existing coil in the oil boiler for DHW in the winter.

Fast forward to about 2 weeks ago and I discovered that both coils attach to the boiler with identical flange patterns. Hmm.... maybe I can just swap the coil and be done with it? Then I could just isolate the oil boiler and only use it emergencies. I did not plan on using it as an active backup.

Tonight I got to tearing the coil out of the oil boiler and slapping it in the VF3000.
Check out the attached pictures. Do you think I will be alright with this coil in my VF3000?
It is a little long. Definitely longer than the Harman coils I have seen in other threads.
There are side pictures of the length of the coil into the boiler.
I figure that I could plumb the PRV into the port directly above the coil, then the next 3 ports would be free and clear of the coil. Then I could install the temp gauge, aquastat and supply piping.
Let me know what you think. Thanks.

here are some other pictures of the coil.

I say it should work just fine.

No problem! Make sure the mixing valve is below the coil... I can't remember... I think 12" was the rule... don't forget the pressure relief for the coil. If you have the extra $20 install two boiler drains and two valves on the coil so it can be segregated and acid flushed when needed.

Do you plan on leaving the oil boiler empty?

Couldn't you get a gasket and solid steel plate to seal it off? That way, "in an emergency", you don't have to drain, the VF3000, pull the coil...blah blah..... you get the idea....

I would think the cost for the plate and gasket should be minimal.

I am a little confused as to what your are doing.

Are you hooking the VF3000 in series with the Crown boiler so the crown can take over if the coal goes out?

If that is the case you should leave the coil for DHW in the crown boiler and just let the VF3000 heat the Crown.

Are you replacing the Crown boiler totally with a VF3000 with oil burner option?

Syncmaster... No. The oil is just going to sit there, valved off until I decide to go away for a few days. My main source of heat will be the VF3000. The oil boiler will not turn on if the coal fire goes out because the oil will be valved and turned off.
I will not have an oil burner option. Coal only.
The Crown boiler is only a few years old. But I don't care if it just sits there. If oil prices go back to where they were last winter, I will still be spending approx. 1/3 to heat the house on coal vs. oil.

Beatle... The oil will be filled and ready to go, just valved off. I still have allot of oil left over from last year. We have 2 oil tanks in the basement, and they are 3/4 full combined.
I do have a plate that I will put on the Crown. It's the one from the VF3000. I just have to get a coupling welded in it for the aquastat. Originally the Crown had the aquastat in the coil plate.

You still should heat the crown to about 140* so it dosen't rust out.
does the crown boiler have it's own chimney?
Or are you using the chimney for the coal boiler?

If you think you might switch back to oil (like going away for 2 weeks).
You should leave the crown boiler alone.
put a cirulator between the Vf3000 and the crown and let the vf3000 keep the crown hot.

If you are using the chimney for the VF3000 then you should disable the crown from firing.
but when you want to go to oil then you would reconnect the crown to the chimney and enable the crown.

If you are using the chimney for the VF3000 then you should disable the crown from firing.
but when you want to go to oil then you would reconnect the crown to the chimney and enable the crown.

Thats what I planned on. I only have 1 chimney, and don't know if I could find a place to direct vent the Crown. Just disable the Crown and disconnect the flue.

Do you really think I will have an issue with the Crown not being heated? It sits there all summer not heated.

I am gonna try to pipe the thing with only 1 circulator total. Keeping it as simple as possible.

When I installed a Solar hot water system on my house.
!20 gal tank and 2 - 4X10 flat plate collectors on the roof, I planed on shutting off my oil burner (weil Mclain P68 oil)
And I was told without a doubt it will turn to rust and the seals between the plates will start leaking.

So I leave my oil burner on , just cut back the temp to 150* from 180* and I end up using about 1 gal of oil per day just keeping it hot in the summer.

The easiest way to hook the vf3k is as follows:
disable the gun on the crown and disconnect the chimney pipe and keep it on the side.
cut the return line from the crown and connect it to the return line input of the VF3k(1-1/4" hole by the stack pipe)
pipe the output of the VF3K (top 1-1/4" hole) to a air trap,air vent,expansiom tank and to return line of the crown.

Now set the crown to 140* , set the VF3k to 160*
when the house calls for heat the circulator on the crown will start, the cold water from the baseboard will return to the VF3k, the hot water will feed from the VF3k to the crown.

The VF3k will start stoking coal and the crown will sit there hot and happy but not burning oil.

I think that is the simplest hook up.