Combi Boiler - Re routing Radiators

[chapmandb]

Hi

I have a combi boiler system (baxi 105HE), which was installed using the original gravity fed system pipe work. unfortunately, the system is depressurising (from 1 bar to 0 in 1 hour). Turned flow and return taps off and checked the pressure; held but when taps turned on again, pressure went to zero indicating a leak in the pipes. No obvious leaks up stairs, but all ground floor pipes are embedded in the solid floor (1975 plumbing), and therefore can't see a leak.

Looks like I have to drop down flow and return from the upstairs bed room radiators to the downstairs radiators (3 radiators), and feed the remaining two downstairs radiators from the main flow and return pipes from the boiler which is also downstairs. Will need to isolate the feed return that go under the solid floor.

Are there any issues in doing this, is it just a simple job, must I be aware of any flow considerations.

Thanks

 

[Andy165]

Do your drops in 15mm pipework and the combi will work nicely. Sounds like you'll need to flush out your pipes aswell to clear any possible sludge from the buried pipework now defunct

 

[bengasman]

Might be worth isolating downstairs pipes to make sure the leak is not somewhere in the old pipes upstairs. Would be a bummer if you found out you were wrong after doing all the work

 

[chapmandb]

Thanks. Wanted to isolate the downstairs, but the way the pipes are configured, would need to do some rerouting anyway, as the feed and return go under the floor and then rise on the other side of the house to the upstairs.

When the boiler was originally commissioned, I had an under floor leak which was easy to spot. When I dug it out, there was a fracture on a 90deg bend. The pipes where just rapped in plastic sheet, with concrete poured over. Just have to take the plunge and reroute so all pipes are above the floor.