zone valves for boilers in series

[carbon neutral]

Hi all,
We are getting settled into our new (to us) home and I want to start on the wood boiler install. We have a oil boiler with coil in it for dhw, the boiler feeds three zones via n/c solenoid valves. I would like to install the wood boiler in series with the oil boiler, using a n/o solenoid valve to recirc the hot water coming from the wood boiler so the oil boiler will stay hot keeping the dhw hot. When a zone calls for heat the n/o valve will shut, the n/c zone valve will open, the entire time the hot water will flow through the oil boiler so dhw will always be available. So has anyone done an install like this and or can anyone recommend a brand model valve that is good for this application (1" n/o valve)? Is there a zone control relay block that is commercially available or will I need to make my own? If I make my own I imagine I will need diodes between the zone valves so power will not travel from one zone to the next.
Any help is appreciated!

 

[Jackpine Savage]

I'm using an Erie PopTop valve and Taco SR501 for the transformer and relay.

 

[Gooserider]

Don't have any advice on the zone valve question, but instead I would ask if there is any alternative method that doesn't involve trying to keep the dino-boiler hot all the time? What I keep hearing is that running the wood boiler water through the dino boiler tends to be a significant efficiency hit - among other things a lot of the heat gets convected up the flue, not to mention what radiates of the outside of the boiler. If you can set it up so the two boilers are in parallel then the dino boiler can sit there cold, and only kick in if needed for standby heat.

Might be worth looking at.

Gooserider

 

[carbon neutral]

I need to keep the "dino" boiler hot since that has the dhw coil in it, I acknowledge this isn't ideal. I will install heat storage and a indirect hot water heater when time and funds permit. This is a temporary arrangemnet that will let me get up and burning now.