How to stop oil boiler from short cycling

[iceguy4]

I plumbed my boiler in series with my oil boiler. I am using my zone pumps to feed the system using all my existing hardware to regulate. I want to keep my oil burner ready incase my wood boiler goes out. I'd rather not add yet another circulator to the 6 I already have (6 zones)
Thanks in advance

 

[peakbagger]

My wood boiler was in parallel with the oil boiler (sort of). I circulated water into the top of the oil boiler via a T on the oil boiler relief valve line and pulled the water off the return header from the circulators. When the wood boiler is running its keeps the wood boiler hot. I obviously am sending some heat up the chimney from the oil boiler but it made the controls easier.

I set up my wood boiler so that if its over 140 degrees F which is the point where I have my wood boiler circulator pump set to come on, I pull in a Normally Closed relay on the power supply to the oil burner. The oil boiler controls remain as before and runs all the zones, it just wont fire the oil boiler. If the power to the wood boiler is turned off, the relay is normally closed and the oil boiler works like it used to. When the wood boiler goes out and drops below 140 the oil boiler kicks on.

I now have a large storage tank that futher complicates the controls but this was how I did it before storage.

 

[iceguy4]

My wood boiler was in parallel with the oil boiler (sort of). I circulated water into the top of the oil boiler via a T on the oil boiler relief valve line and pulled the water off the return header from the circulators. When the wood boiler is running its keeps the wood boiler hot. I obviously am sending some heat up the chimney from the oil boiler but it made the controls easier.

I set up my wood boiler so that if its over 140 degrees F which is the point where I have my wood boiler circulator pump set to come on, I pull in a Normally Closed relay on the power supply to the oil burner. The oil boiler controls remain as before and runs all the zones, it just wont fire the oil boiler. If the power to the wood boiler is turned off, the relay is normally closed and the oil boiler works like it used to. When the wood boiler goes out and drops below 140 the oil boiler kicks on.

I now have a large storage tank that futher complicates the controls but this was how I did it before storage.

My boiler uses a Taco SR 506 6 zone controller...

 

[iceguy4]

My wood boiler was in parallel with the oil boiler (sort of). I circulated water into the top of the oil boiler via a T on the oil boiler relief valve line and pulled the water off the return header from the circulators. When the wood boiler is running its keeps the wood boiler hot. I obviously am sending some heat up the chimney from the oil boiler but it made the controls easier.

I set up my wood boiler so that if its over 140 degrees F which is the point where I have my wood boiler circulator pump set to come on, I pull in a Normally Closed relay on the power supply to the oil burner. The oil boiler controls remain as before and runs all the zones, it just wont fire the oil boiler. If the power to the wood boiler is turned off, the relay is normally closed and the oil boiler works like it used to. When the wood boiler goes out and drops below 140 the oil boiler kicks on.

I now have a large storage tank that futher complicates the controls but this was how I did it before storage.

Peek,
As for sending heat up the chimney...Field controls has a jim dandy elertric vent damper for oil units. Its a well built unit with stainless "fingers" that is purpose built for oil. Mine has been on for over 2 years and works very well Its in this picture. It wont let the burner fire till its open and remains open for 3 min after the burn.