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.
Unlike conventional boilers, combi-boilers donât need a tank to store hot water, instead they heat on demand and come in gas, electric, and oil-fired versions. The cost of a new combi-boiler will vary depending upon how large your system needs to be and where you purchase it from. For instance:1  A Vaillant combi boiler purchased straight from the producer prices between GBP725 and GBP910.his guide is going to cover the costs involved when installing various types of boilers, including combi, gas, oil and electric boilers. Weâll also give you tips for finding a boiler engineer and we will also supply you with all the information on related installation grants.