Just wondering on the best way to go when getting rid of the boiler. Obviously we are set up for a condensing boiler so if we just lifted the old one off the wall and bolted a new one in place (simplification I know) would that be a good option or should we take the opportunity to replace with a combi. House is 1930's with 4 rads downstairs, heated towel rail in bathroom, 3 rads upstairs, house has electric shower. Thanks in advance