Adding Radiator to existing radiator with 10mm pipe

[jona476]

Hi

I want to add a radiator in my conservatory. I have a Biasi condensing combi boiler which is 12 months old and more than capable.

The closest existing radiator to the conservatory is about 6ft away in the dinning room. From what I can see the flow & return pipes to this radiator
are 15mm in the floorboards but are reduced down to 10mm on the drop down the wall to the radiator.

I was wondering if I could tee off the flow & return pipes at the back of this radiator (10mm pipes) or will I have to go back to the 15mm in the floorboards. ie would teeing into the 10mm pipes be too much of a flow resriction.

Also I believe I have to put isolator values before the pipes exit the house.

Thanks

 

[gas4you]

In theory a conservatory rad needs its own time control, room stat and zone valve to make it totally independent from the main building heating system.

However if your conservatory is a few years old then new regs MAY not apply to it.

Go back to the 15mm pipes to T into these.

 

[nashville]

I've just done exactly what you are planning to do and wish I hadn't.

I tee'd off the 10mm pipes on dining room rad, and ran new 10mm pipe to a new large rad in the conservatory a few feet away.

Flow to the new larger rad was v. disappointing, won't fully heat up.

Like yours, my 10mm pipes drop down from above. It seems the water takes the easy route through the existing smaller rad, and doesn't really like going through the bigger rad which requires more effort.

If the new rad in your conservatory is to be the same size or smaller than the existing one, teeing off might work. But fitting a small rad in a conservatory won't be enough to heat it.

I'm now going to run dedicated 15mm pipes to my new rad from the main pipes in ceiling to improve things, you may want to think about doing this too!

 

[gas4you]

I've just done exactly what you are planning to do and wish I hadn't.

I tee'd off the 10mm pipes on dining room rad, and ran new 10mm pipe to a new large rad in the conservatory a few feet away.

Flow to the new larger rad was v. disappointing, won't fully heat up.

Although you shouldn't have teed off the 10mm pipe, this will at best only carry about 3kw, have you balanced down the lockshield of your existing rad?

 

[jona476]

Thanks for your quick replys & advice.

 

[jona476]

Hi

Although you shouldn't have teed off the 10mm pipe, this will at best only carry about 3kw, have you balanced down the lockshield of your existing rad?

gas4you - You say 3Kw at best. The rad I am putting in is 1.7kw (5700btu). Although going back to the 15mm is the proper way to do things, do you think at 1.7kw and also balancing, it may work?

I'm looking at all alternatives before going back to the 15mm as this will involve taking up the laminated floor in the bedroom and also because the house is only 11 years old it has got those crappy chipboard floorboards, which are a nightmere to get up.

I did the same thing in a house a lived in a few years ago. This worked for the first winter season but when I switched the heating on for the next season the radiator in the conservatory and the one I tee'd off only got luke warm with thermo at 20-22. The other rads in the house where ok. But if you turned the thermo above 26 all rads where red hot. I just put this down to the boiler not being man enough (old glow-worm system with water tank) or the fact I never balanced the rads.

Thanks

 

[chrishutt]

You could upgrade the drops from the floor above to 15mm without actually going into the floor. Just connect new 15mm pipes to the 10mm pipes poking down through the ceiling. Although this will leave short sections of 10mm in the run, the flow resistance from these will be greatly reduced (in proportion to their length) compared to the existing situation.

 

[jona476]

Thanks for the reply Chrishutt.
Something I didn't think about, good idea, but I would still have to go into the floor as the pipes run down the back of the plaster board.
Thanks