Stacy, the bathroom project looks great, thanks for all your help! Emergency or not, we want you to have complete confidence in the work our plumbers do that's why we've created the aspect.co.uk guarantee. I don't understand much on how the plumbing appliances work kurt explained the appliances to me! i highly recommend him for your plumbing and heating needs! The deg flue elbows are suitable for condensing boilers only. Thanks for printing! don't forget.