I was up-against-the-wall when temperatures dipped (with windchill) to -18C in winter 2017. My boiler outflow froze solid like many others on the street & ended up completely bursting my boiler. I had dc to care for and every bloody plumber the world over had a 3 week waiting list. I tried EVERYWHERE. In sheer desperation, I had no other option but to use a well known company I don't dare name. Today, I've found out what a shitey job they did. My boiler was serviced & the new local plumber showed me how the other company had substituted really excellent Vaillant seals for the poxiest shite you've ever seen! He was appalled & so am I. They had me over a barrel that winter. NEVER AGAIN. 