DIY Doctor

Pro Combi Boiler Advice

Postby tomonl » Tue Nov 01, 2011 12:27 pm


Im currently having a central heating system installed in my house and the Pro combi boiler was installed yesterday.

The boiler has 6 input/outputs on the bottom and as im abit of a worrier (especially when it comes to gas and electrics) i was just wondering what these are for. When i asked my installer he just told me they were, gas, cold water in, hot water out and the flow and return for the central heating. Yet there is a 6th valve that he didnt explain. As all pipeworks currently exposed i wouldnt mind checking it before my installer comes back on thursday just for piece of mind.

Im sure its all fine and safe but as i said i worry about these things!

thanks for any help.
Rank: Labourer
Progress to next rank:
Posts: 3
Joined: Tue Nov 01, 2011 12:17 pm


Simply Build It

Postby plumbbob » Tue Nov 01, 2011 4:01 pm

I am sure you don't need to worry about this as your installer will be well aware of which pipe is which and what they do. He wouldn't be Gas Safe registered if he didn't.

In fact there are seven connections to the boiler not six. Apart from the five you have mentioned, there is a connection to a safety relief valve which is to vent excess pressure should the boiler develop a fault.

The final connection is a white plastic pipe to drain any condensation which forms in the heat exchanger and flue.
Rank: Project Manager
Posts: 1891
Joined: Wed May 07, 2008 9:59 pm

Display posts from previous
Sort by
Order by

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics