According to the manufacturer's information OV PULSAcoil thermal stores are primarily designed for use with on/off peak electricity but also have two open pipe spigots (NO internal coil) for flow and return from an additional heat source e.g. a heat only boiler. The 180 store comes with a manually filled circular feed and expansion tank that fits directly on top of the store together with all the fittings and preformed piping required to connect the tank to the store. Consequently the expansion tank is only sized for the thermal store and due to its design cannot be fitted with a ballcock for automatic fill. Those wishing to have the additional heat source spigots connected to the flow and return of the boiler serving their existing OV system must purchase a replacement expansion tank sized for the store, the boiler and radiators, etc., and install it above the highest point in the system.
Based on the above I presume I'm looking at the end result being similar in nature to the attached diagram (DHW plate heat exchanger omitted) where the existing boiler feed and vent pipe are relocated to the new tank along with the new store fill and vent pipes or is there a better alternative? I note that most thermal store vent pipe rise and enter their feed and expansion tank at the top side whereas the boiler vent rises so that the top of the pipe is 450 mm above the level in the tank before bending down to just enter the tank. If the criteria is the height above the water level before entering the tank can't it be treated in a similar manner and enter into the top side of the tank?
Thanks in advance for any comments.
Based on the above I presume I'm looking at the end result being similar in nature to the attached diagram (DHW plate heat exchanger omitted) where the existing boiler feed and vent pipe are relocated to the new tank along with the new store fill and vent pipes or is there a better alternative? I note that most thermal store vent pipe rise and enter their feed and expansion tank at the top side whereas the boiler vent rises so that the top of the pipe is 450 mm above the level in the tank before bending down to just enter the tank. If the criteria is the height above the water level before entering the tank can't it be treated in a similar manner and enter into the top side of the tank?
Thanks in advance for any comments.
