As a certified plumber, you may write the interprovincial exam to qualify for the interprovincial standards’ red seal with a red seal, you can work as a plumber anywhere in canada. Based in london or berkshire? come to our windsor office to see the boilers in action. Dyno-rod have been unblocking drains nationwide for nearly 40 years dyno-rod cannot be matched by any other company in this regard we’ve seen it all, we’ve cleared it all! Have you reviewed this troubleshooting guide from the manufacture?.