Radiator pipe extension = cold Rad

[cravenbiker]

Hi

I extanded the pipes from the main flow and return to my radiator (the pipes that branch off to the rads- lets call them mini F & R for tihs post) by about a meter and added an elbow on both mini f & R and now the mini flow gets hot all the way up to the rad but rad doesnt get hot & obviously neither does the mini retrn pipe.

I have bled the rad fully and there is water in it .
s it possible i have extended the mini f&r too much and now its too far from the Main f&r to get water pushing through it?

any way i can test this?

If it is too far is there some sort of inlie pump i can get for that rad only?

Thanks

Tris

 

[TicklyT]

Sounds like a blockage. Are both the wheelhead/TRV and the lockshield valves open? Have you bled the radiator?

Have you tried disconnecting the valves from the rad. and running water from them into a bucket? Water should run freely from both the feed and return.

What size is the pipework? 15mm or microbore?

 

[jim80]

Hi cravenbiker,

I think from your post that you have moved an existing rad which meant you had to lengthen the pipes and turn a corner which needed a new elbow on each pipe. Yes?

Ok the info we know.

Heated water is reaching the rad valve. Yes?

No heated water is getting into the rad. Yes?

No heated water is leaving the rad. Obviously Yes.

Normally if the pipe gets hot and stops at the rad - we go straight to the valve to make sure it is open or has opened by itself if its a TRV.

Check this first, also the valve at the other end (return end) of the rad.

Make sure they are open. Your rad will fill up and can be bled with one valve closed - being full of water doesn't mean it should work.

Are the valves new or old ones? Are they sticking/ dirty? If these questions check out ok, then it may be a balancing issue - although moving a rad by 1 metre shouldn't affect the balancing.

An air lock created by not fitting the pipework horizontally could affect the flow as well but I think I'm straying away from my main point that heated water is already flowing to your rad.

Check the valves first.

jimbo

 

[cravenbiker]

Sounds like a blockage. Are both the wheelhead/TRV and the lockshield valves open? Have you bled the radiator?

Have you tried disconnecting the valves from the rad. and running water from them into a bucket? Water should run freely from both the feed and return.

What size is the pipework? 15mm or microbore?

Thanks for the reply, all 15mm copper

Trv & Locksheild fully open, Rad bled

I will take the rad off today and see if there is water coming from f & R
I didnt think that there would be water from the return too but thinking about it, it makes sense.

I thought maybe there was access solder from when i welded the elbow that is blocking it but there woud need to be a serious amount of solder to create a blockage. If it is blocked, could i flush it chrough with a hosepipe? is the a way of flushing the pipes through without taking the rad off? ie shutting the trv and putting some sort of fitting onto the bleed valve that i can stick a hosepipe on?

Thanks again.

 

[cravenbiker]

Thanks for your replies guys, the rad is miraculously red hot now.

God knows why? do you thnk it could have been a sticky trv? it is brand new or something in the return pipe from when i extended it. i remember putting some blue roll in the pipe to stop excess water coming out. i cant remember if i took it out or not so im a bit woried now that it'll get stuck in the pump if that was the case. guess only time will tell ) bloody amatures

Many thanks again

 

[cravenbiker]

Jst out of interest, whas the maximum distance that you shoud have a rad from the main pipework if using 20mm-15mm or does it all depend on pump, size of house, no. f rads etc?

Any rough ideas for a normal 3 bed house with 8 rads and a 20 year old vented system?

Thank you