1 In the Format Cells dialog box, click Color, and then click the White square. 2  Click OK in the Format Cells dialog box, and then click OK in the Conditional Formatting dialog box. 3  Note Because you selected column A in step 2, all the cells in column A were formatted with this conditional format. In the Format Cells dialog box, click Color, and then click the White square. 2  Click OK in the Format Cells dialog box, and then click OK in the Conditional Formatting dialog box. 3  Note Because you selected column A in step 2, all the cells in column A were formatted with this conditional format.
With maintainance a boiler should last 15 years. A combo boiler is used more than any other boiler because of constant demand.A heat exchanger replacement you have to consider age and shape of unit.ith maintainance a boiler should last 15 years. A combo boiler is used more than any other boiler because of constant demand.
Some combination boilers don't operate when the pressure is below 1 bar, this is a safety device to stop any further problems occurring to the boiler, so always keep your combi boiler pressure above 1 bar and below 2 bars.