Draining heating system

[GR8GUY]

Hi all, This is probably an easy question but Im puzzled and need some advice.
The pics are of my upstairs radiator pipe which has started to leak into my dining room. The plumber who fitted this intended to take a feed from this and run it into extension. He changed his mind and took a feed from another room instead but left this little mess for me.
It is now leaking from bottom part of the main tee connected to radiator.
I intended to drain my system and replace with just a straight tee and new bottom olive and nut onto a new peice of 8mm pipe. I opened the outside drain cock and the radiator air vents.The system was draining fine but after about 20 mins the water coming out was hot. Why can this be as the heating has been turned off for a week or so ? Ive stopped mid job as I cant work out whats going on. I think this is a an indirect system as the loft has a large tank and smaller one on top for radiator filling. Can you help ?

[htg engineer]

I don't believe a plumber has done that work, basically take the tee out completely as teeing into 10mm and increasing to 15mm to feed another radiator will never work.

You need to take the flow and return to the extension directly from the manifolds or 22mm flow and return.

Turn off cold water, drain system. Take tee out and re-connect existing radiator.

If you're getting hot water it's possible the tank coil is damaged- you'll be draining the domestic hot water tank.

I'd ask for a refund, because he's not a plumber.


htg

[GR8GUY]

Thanks htg ! Yes I totally agree the guy certainly turned out to be a cowboy. I hadnt realised he left it like that as it was behind a bed.
I replaced the tee with a straight connector this evening and refilled the system. The heating all works fine now with no leaks. I'll not to be so trusting next time :x

[plumbbob]

The system was draining fine but after about 20 mins the water coming out was hot. Why can this be as the heating has been turned off for a week or so ?

I assume you have turned the boiler off so it is not heating the hot water??
The coil in the cylinder will contain a small amount of hot water so you might find a small quantity of hot water during the draindown.

After the drain has been running for 10 mins or so, check the header tanks in the loft. Take particular note of the larger one. If it is filling up, you may have a faulty cylinder coil.

[GR8GUY]

Hi Plumbob,
Yes I think thats exactly what was happening.The heating was turned off but the hot water was still on and i was just getting some heated water as last of it was being drained. Every day is a school day!
Thanks :D

[TheDoctor4]

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