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.
The average price of a new gas combi boiler including installation is around $3,700 (Â£2,300). The final price of the combi boiler cost includes: 1  Cost of the boiler. 2  Cost of installation. 3  Cost of fittings and Accessories. 4  Cost of removing old tanks or old systems.