Cannot get new radiator to heat up?

[mbc0]

Hi,

I have just replaced an old radiator with a new Revive 500h x 1100l Double Premium Radiator (P+) but cannot get it to heat up? The right hand pipe gets very very hot but it does not flow through the radiator.

when I drained down the system (I had other radiators to replace and pipework to move) I installed isolators on the pipes coming from out of the floor to allow me to install it at a later date but keeping the other radiators on in the house. I removed the radiator checked for blockages, tested the isolators and valves and found that the water flow from the pipe on the left is very powerful (think garden hose) but the pipe on the right is approximately 20% of that pressure, is this normal? is it because it is the return?

The TRV is uni-directional and removed to be fully open for the moment.

I have turned the other 8 radiators off on the ground floor & the 3 upstairs just leaving this one and left the bleed valve open running into a bucket for about 20 minutes. This results in the rad getting hot but it cools down again after a while when I shut the bleed valve off.

Do I have an issue with the pipework possibly? Any ideas?

Picture in the link belowMany Thanks in advance.

20190130_164436.jpg

 

[Harvest Fields]

Did the old radiator get hot or did you have the same issue?

 

[Riley]

could you post a pick of it?? Is it a column style rad?

 

[SJB060685]

It sounds like you have a restriction on right pipe (return I presume) drastically reducing flow through radiator and when the bleed is open this is allowing flow? This could be caused by a number of things

 

[SimonG]

Kinked pipe under the floor.

Oh and get them isolators removed. Looks gash and not rated for central heating.

 

[snowhead]

If the isolators are just standard ones and not full bore, then they are the problem.
If you look inside they reduce to about 8mm.

 

[mbc0]

Did the old radiator get hot or did you have the same issue?

Hi,

I have removed and reinstalled again today (because of the isolators I installed) but cannot seem to get it hot at all (just red hot on the right pipe which has the very weak flow)

I do think it did work when I first installed it but as it is a spare room it was not monitored, so cannot be 100%

 

[mbc0]

If the isolators are just standard ones and not full bore, then they are the problem.
If you look inside they reduce to about 8mm.

Hi, With the isolator removed on the right side pipe the water just dribbles out but with the isolator installed on the left the water is powerful like a hose so surely the isolator wouldnt cause an issue? I was trying to find out if this was normal having one pipe so powerful and the other not?

 

[mbc0]

If the isolators are just standard ones and not full bore, then they are the problem.
If you look inside they reduce to about 8mm.

Hi, With the isolator removed on the right side pipe the water just dribbles out but with the isolator installed on the left the water is powerful like a hose so surely the isolator wouldnt cause an issue? I was trying to find out if this was normal having one pipe so powerful and the other not?

 

[mbc0]

could you post a pick of it?? Is it a column style rad?

Hi, the pic is linked at the bottom of my original post

 

[Riley]

Well as we said. Isolators are not for central heating so could very well be the problem

 

[mbc0]

Linked pipe under the floor.

Oh and get them isolators removed. Looks gash and not rated for central heating.

Hi, what do you mean by linked pipe? I have those isolators on 2 other radiators that work perfectly. I do hear what you are saying and will replace them all for full bore but the other 2 rads are working fine with those isolators.

 

[Riley]

No don’t replace them take them out they aren’t for central heating

 

[Riley]

Plus it doesn’t mean the one on the other pipe isn’t clogged

 

[mbc0]

Well as we said. Isolators are not for central heating so could very well be the problem

Hi, I do understand and will remove them but the pressure does not change with them on or off, the right hand pipe is merely a dribble. The other 2 rads with isolators have been working perfectly since October 17.

 

[SimonG]

Hi, what do you mean by linked pipe? I have those isolators on 2 other radiators that work perfectly. I do hear what you are saying and will replace them all for full bore but the other 2 rads are working fine with those isolators.

Kinked, bloody predictive text.

It's not a case of them working. It's a case of them not being rated for central heating installation.

 

[mbc0]

Plus it doesn’t mean the one on the other pipe isn’t clogged

Hi, I changed the isolator today from a Plumb base to a peglar, even with the isolator removed the pressure does not change, it is still a dribble

 

[mbc0]

Kinked, bloody predictive text.

It's not a case of them working. It's a case of them not being rated for central heating installation.

Ah, I see.. I will remove them it is not a problem, I was just thinking I was being savvy for the future! The pipes are bedded in concrete for this room long before I came along so don't think they could be kinked.

 

[SimonG]

Why are there two sets of pipe coming out the floor?

 

[SJB060685]

I assumed he re did so to have right centres lol

 

[mbc0]

Why are there two sets of pipe coming out the floor?

ah, the other pipe on the left that you see is a pipe for the garden hose, it is connected to the mains, nothing to do with this. for the radiator there are two pipes, 1 each side of the radiator.

 

[mbc0]

is everyone saying don't use isolators or don't use the ones I have used? I see plenty of radiator pipe isolator's at screwfix/victoria plum etc.

 

[SJB060685]

Screwfix and Victoria Plum says it all lol

 

[Riley]

Don’t use isolators. They aren’t designed for the heat or for the crud that goes round in the pipes

 

[snowhead]

And they always leak when you come to turn them off /on