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Low loss header for dual heat sources

aqueconick Member Posts: 1

First of all I should tell you I'm from England, so some of the terms might be unfamiliar (and I probably spell things funny too!). Please ask me to clarify anything that's not clear.

I have a customer who wants me to add an electric boiler to a system I installed a couple of years ago. It currently has a wood stove using gravity circulation to heat a thermal store, which also has the header tank above it. This is for hot water only (it has a heat exchange coil inside to give mains pressure hot water). The heating side is pumped from a connection teed into the primary flow and return from the stove to the thermal store. There's an injector tee where the two returns meet and a swing check valve on the primary flow to prevent reverse circulation from the store to the stove. Can I use a low loss header to get both heat sources (electric boiler and stove) to do the central heating? The thermal store has an immersion heater, so no need for the electric boiler to do that. How might a low loss header affect the gravity circulation if both heat sources working at once?

Many thanks,



  • SWEI
    SWEI Member Posts: 7,356
    edited April 2014
    If this is for space heat only

    I would pipe an electric boiler in series with the existing distribution system.  Head loss is minimal and it simplifies things quite a bit.

    What is the design-day heat loss for the building?  Thermolec makes the only electric resistance boilers I am aware of smaller than 10 kW with built-in ODR control.
  • heatpro02920
    heatpro02920 Member Posts: 991
    I normally

    Pipe dual heat sources primary secondary, makes thisgs work very well and pretty simple to do..