Furnace with Manifold for Controlling Supply of Heated Liquid to Multiple Heating Loops

Abstract

A furnace includes a pump in a circuit through a heat exchanger and a manifold having a plurality of discharge openings in a first area and return openings in a second area connected by a transfer area with each discharge and return feeding a respective heat loop. A bypass in the circuit includes a temperature controlled protection valve connected between the bypass and the manifold. The heated liquid inlet of the manifold is connected to the manifold in the first area with the plurality of discharge openings at a position between the plurality of discharge openings and the plurality of return openings. The manifold is defined by a rectangular chamber divided longitudinally and diagonally by a transverse wall which terminates at one end at a position spaced from an adjacent end of the chamber to define an undivided portion of the chamber at the end which forms the transfer area.

1 . A furnace for heating a heat transfer liquid comprising:
 a furnace heat exchanger having a heated liquid outlet and a cooled liquid return so that cooled liquid returned to the return passes through the furnace heat exchanger to be heated and discharged through the heated liquid outlet;   a heating system in the furnace for applying heat to the furnace heat exchanger to heat the liquid;   a furnace pump for pumping the liquid in a circuit through the furnace heat exchanger;   a manifold connected in the circuit between the liquid outlet and liquid return;   the manifold having a heated liquid inlet for receiving the heated liquid from the heated liquid outlet and a cooled liquid outlet for supplying cooled liquid to the liquid return;   the manifold having a plurality of discharge openings and a plurality of return openings;   the discharge openings being collected in adjacent positions in a first area of the manifold and the return openings being collected in adjacent positions in a second area of the manifold with the first and second areas being connected by a transfer area of the manifold for transfer of liquid therebetween;   each discharge opening being associated with a respective return opening for connection to a respective supply loop including a respective loop pump and a respective output heat exchanger for heating a respective zone with liquid being extracted from the manifold by the loop pump through the respective discharge opening and returned to the respective return opening;   the heated liquid inlet of the manifold being connected to the manifold in the first area with the plurality of discharge openings at a position between the plurality of discharge openings and the plurality of return openings.   
     
     
         2 . The furnace according to  claim 1  wherein there is provided a bypass in the circuit for liquid to bypass the manifold and a temperature controlled protection valve connected between the bypass and the manifold, the valve being operated to control flow between the manifold and the bypass such that when liquid at the cooled liquid return is below a predetermined temperature the valve operates to halt passage through the manifold and, as a temperature of the liquid increases, the valve is opened to allow passage through the manifold dependent on the increasing temperature. 
     
     
         3 . The furnace according to  claim 1  wherein there is provided no temperature controlled protection valve in the loops. 
     
     
         4 . The furnace according to  claim 1  wherein the heated liquid inlet of the manifold is connected to the manifold in the first area separate from the transfer area between the plurality of discharge openings in the first area and the plurality of return openings in the second area. 
     
     
         5 . The furnace according to  claim 1  wherein cooled liquid outlet is connected to the transfer area. 
     
     
         6 . The furnace according to  claim 1  wherein a sum of volumes pumped by the loop pumps is different from a volume pumped by the furnace pump. 
     
     
         7 . The furnace according to  claim 1  wherein a sum of volumes pumped by the loop pumps is greater than a volume pumped by the furnace pump and allowed to pass through the manifold by the protection valve. 
     
     
         8 . The furnace according to  claim 1  wherein the protection valve is connected between cooled liquid outlet of the manifold and the bypass. 
     
     
         9 . The furnace according to  claim 1  wherein the protection valve controls discharge of liquid from the cooled liquid outlet of the manifold. 
     
     
         10 . The furnace according to  claim 1  wherein the protection valve is connected to the manifold at the transfer area. 
     
     
         11 . The furnace according to  claim 1  wherein the manifold comprises a chamber divided longitudinally by a transverse wall into the first area on a first side of the wall and the second area on a second side of the wall and wherein the transverse wall terminates at one end at a position spaced from an adjacent end of the chamber to define an undivided portion of the chamber at said end which forms the transfer area. 
     
     
         12 . The furnace according to  claim 11  wherein the heated liquid inlet of the manifold is arranged on one side the transverse wall in the first area. 
     
     
         13 . The furnace according to  claim 9  wherein the chamber is rectangular in cross-section to define four walls at right angles with the discharge openings in a first wall and the return openings in a second wall. 
     
     
         14 . The furnace according to  claim 11  wherein the chamber is rectangular in cross-section to define four walls at right angles with the discharge openings in a first wall and the return openings in a second wall at right angles to the first wall with the transverse wall arranged diagonally to the first and second walls. 
     
     
         15 . The furnace according to  claim 14  wherein the heated liquid inlet is located in a third wall. 
     
     
         16 . The furnace according to  claim 15  wherein there is a transfer channel for the heated liquid along the third wall for carrying the heated liquid to the inlet therein. 
     
     
         17 . The furnace according to  claim 15  wherein the cooled liquid outlet is in a fourth wall. 
     
     
         18 . A furnace for heating a heat transfer liquid comprising:
 a furnace heat exchanger having a heated liquid outlet and a cooled liquid return so that cooled liquid returned to the return passes through the furnace heat exchanger to be heated and discharged through the heated liquid outlet;   a heating system in the furnace for applying heat to the furnace heat exchanger to heat the liquid;   a furnace pump for pumping the liquid in a circuit through the furnace heat exchanger;   a manifold connected in the circuit between the liquid outlet and liquid return;   the manifold having a heated liquid inlet for receiving the heated liquid from the heated liquid outlet and a cooled liquid outlet for supplying cooled liquid to the liquid return;   the manifold having a plurality of discharge openings and a plurality of return openings;   the discharge openings being collected in adjacent positions in a first area of the manifold and the return openings being collected in adjacent positions in a second area of the manifold with the first and second areas being connected by a transfer area of the manifold for transfer of liquid therebetween;   each discharge opening being associated with a respective return opening for connection to a respective supply loop including a respective loop pump and a respective output heat exchanger for heating a respective zone with liquid being extracted from the manifold by the loop pump through the respective discharge opening and returned to the respective return opening;   wherein the manifold comprises a chamber divided longitudinally by a transverse wall into the first area on a first side of the wall and the second area on a second side of the wall and wherein the transverse wall terminates at one end at a position spaced from an adjacent end of the chamber to define an undivided portion of the chamber at said end which forms the transfer area.   
     
     
         19 . The furnace according to  claim 18  wherein the heated liquid inlet of the manifold is arranged on one side the transverse wall in the first area. 
     
     
         20 . The furnace according to  claim 18  wherein the chamber is rectangular in cross-section to define four walls at right angles with the discharge openings in a first wall and the return openings in a second wall at right angles to the first wall with the transverse wall arranged diagonally to the first and second walls.