Do plumbers offer a written warranty? Boiler help, fixes, advice and buying guides. Really impressed with the efforts made by the company very clear pricing and excellent professional knowledge.”. Is your network connection unstable or browser outdated? That’s good news when it comes to both installation as well as servicing as it simplifies the process for the engineer and ultimately should cost you less in time and therefore money. At clas ohlson you can always shop securely and fast you always have a up to -day refund policy next day delivery available.