Isar Information

Isar Combination Boiler

3 Models HE24, HE30 & HE35. These give different hot water outputs see flow rates

Sedbuk

Older Isar model m30-100 ceased production October 2003 can be distinguished by only has user control without gray panel across front.

Boilers can be fitted within cupboards with no ventilation, but minimum clearances must be maintained for service. See page 9 Inst & Serv

To confirm size of boiler or that correct PCB links for size of boiler, turn off power by on / off switch. When boiler comes back on it will briefly display a number

7 = isar HE24, 5= HE30, 4=HE35

 

 

 
isar cuir
OPERATION

With no demand for Heating, the boiler fires only when Hot Water is drawn off, or periodically for about 1 minute without any DHW draw-off, in order to maintain the DHW calorifier in a heated condition.
When there is a demand for CH, the heating system is supplied at the selected temperature of between 30oC and 82oC until DHW is drawn off. The full output from the boiler is then directed via the diverter valve to the
plate heat exchanger to supply a hot water. At low DHW draw-off rate the maximum temperature is limited to 65oC. Due to system variations and seasonal temperature
fluctuations DHW flow rates/temperature rise will vary, requiring adjustment at the draw off tap.

 

Flueing can be

Standard horizontal up to 6m HE24 & HE30, 3m max HE35, deductions must be made to maximum flue length for each bend (other than initial bend off boiler) 90 bend deduct 1m, 45 bend deduct 0.6m.

External plume management can also be fitted. see page 48 flue guide.

Vertical flues can be run to a maximum of 8m 24 & 30 and 5m HE35. Deductions as above.

Twin pipe flues are available in 60mm & 80mm diameters which allow for very long flue runs up to a maximum of 46m. See flue guide for full details