No central heating - disaster on a night like this!!

[homertimpson]

Attempted to change a radiator this afternoon.
Replaced it with a smaller one - it's microbore inlets.

Drained the system - removed the rad - put the new one on the wall, but I cannot get the 8mm elbows tight enough - they are just proving impossible

No heating for 6 hours - wife is going ballistic - we're in bed with a borrowed 10 year old single bar electric heater. I'm right in the doghouse.

Tomorrow I intend to cut away the existing couple of feet of 8mm that the builders soldered onto the 15mm pipe I can see below the floorboards.

Will it be ok to have one small rad fed by 15mm when the rest of the house rads are on 8mm?

I need to get the heating on ASAP tomorrow.

This will be transferred to DIY Disasters eventually - in 30 odd years of small DIY jobs this is the biggest cock-up I've made.

Homer

 

[bathjobby]

Will it be ok to have one small rad fed by 15mm when the rest of the house rads are on 8mm?

Yes, just use the rad valves to regulate it...

 

[chrishutt]

You should use soldered fittings with 8mm tube. Compression fittings don't work too well due to the softness of the tube.

 

[homertimpson]

Thanks guys - I survived the night!! Will not see another though if this isn't fixed by the time my missus gets home tonight

Thanks for the advice. 1st time I've tried to use 8mm. Not for the DIY man with compression - soldered if ever I need to try it again.

Will be out at lunch getting the required 15mm pipe and fittings - then a half day off work to get this done right.

Thanks again for the help.

Shivering Homer

 

[ChrisR]

but I cannot get the 8mm elbows tight enough

EH? are they leaking? -use compound.
Do you mean BENDS? Use elbows, solder ring, endfeed, compression..

wife is going ballistic - we're in bed with a borrowed 10 year old single bar electric heater. I'm right in the doghouse.

Your wife is airborne, but still in bed, with an electric fire. That sounds dangerous. And part of the bed is where the dog lives...

 

[nstreet]

Attempted to change a radiator this afternoon.

Out of necessity I hope, especially at this time of year.

 

[homertimpson]

I have heating

Replaced 8mm sections with 15mm and restarted feeder tank.

Small leaks from each elbow

Gave each a slight turn - leaking stopped

Bled system and turned on heating for 10minutes. [pump only]

Started boiler at low setting and eventually the heat came through.

A few airlocks were stopping the lounge and hallway from getting any hot water at all. 30 minutes later the house had warm rads with the exception of the same 2 that were still cold. Embarrisingly, I realised I'd missed the small rad in the ensuite - it was cold at the top and duly hissed when bled. Within minutes the 2 downstairs rads were heating up

2 hours later and the house is warming up very nicely

2 straights, 4 elbows and the new rad connections are still leak free.

Please let it be permanent.

I had hoped to fit TRV's to several of the rads whilst the system was drained but, as they are all 8mm valves, I think I shall have to reconsider a better approach to this. [I'd thought about fitting the new TRV to the rad, cutting out a small piece of pipe and then inserting a solder type straight coupler to take up the space. Does this sound feasible?]

This will be put on hold until the better weather!!


Thanks again for the replies.

Homer

 

[Paul Barker]

You can buy 8mm trv's.

Junior hacksaw olive until you can get small flat screwdriver in slot and ping it off, apply compound to pipe and new olive reassemble with new trv, repeat on each rad. Easy once you get into the swing of it.

My advice is don'tr buy the trv's with 10mm and 8mm options, get 8mm trv's.

 

[homertimpson]

Junior hacksaw olive until you can get small flat screwdriver in slot and ping it off

Sorry for being dense - but talk me through it again

Drain system.
Remove old trv - this will leave 'nut & olive attached to pipe'?
Hacksaw off this olive, remove nut, use new nut & olive with existing pipe and TRV along with compound.

Should I attach the TRV to the rad first before trying to tighten up the nut and olive?

Sorry for asking for step by step - but the past few days were a nightmare and I want to get it right when I try the TRV's.

Regards

Homer