Which is flow and return ?

[colin H]

I`m just about to replace a radiator in my hallway , but not sure which pipe is flow , and which is return . The current rad has 2 identical valves , with no thermostat .

Ive tried holding the pipes when the heating kicks in to see which heats up first , but there doesn`t seem to be much between them . Its a vertical type rad , 450mm wide , by the way .

However , I have noticed that after about 15 mins , the left side of the rad is considerably warmer than the right . Is it safe to assume that the left is the flow , side ? I`d rather avoid taking up any floors to investigate further , if possible .

Thanks , Colin .

 

[ianmcd]

wont matter which is which, if you are planning on installing a TRV just get a Bi-directional one most these days are anyway , if you are keeping the same valves and not fitting a column rad it wont matter

 

[colin H]

Thanks Ian - much appreciated !

 

[Razor900]

If you really need to know start with the system cold, close the valves off to the rad and run the heating system for half an hour then open the valves. The flow will now be considerably hotter than the return - but not for long!

 

[colin H]

Thanks , I`ll try it - just out of curiosity

 

[D_Hailsham]

Its a vertical type rad , 450mm wide , by the way .

If you are replacing it with another vertical rad, it may be important to know which is flow and which return as some radiators need to be connected in a specific way. It's due to internal baffles to ensure the water rises up the rad.

 

[durhamplumber]

Thanks , I`ll try it - just out of curiosity

Jeez.Gan to the pub instead Colin,,ffs.

 

[BigClick]

If you are replacing it with another vertical rad, it may be important to know which is flow and which return as some radiators need to be connected in a specific way. It's due to internal baffles to ensure the water rises up the rad.

I understand you can see or feel the baffle on a vertical radiator from the inlet point of the vertical radiator

 

[ivixor]

The baffle just determines which way up the radiator is. You can still feed it from either side.

 

[D_Hailsham]

The baffle just determines which way up the radiator is. You can still feed it from either side.

If you are correct, why do some vertical rads have there connections specifically marked Flow and Return? There have been several topic, on this forum and others, about the problem of incorrectly piped vertical rads.

 

[gasbusters]

Just fit bi-directional valves, you wont have any issues.

 

[dilalio]

All of the vertical rads I've fitted have to have correct orientation to the flow and return, as marked on the rad with little yellow stickers. On a double column rad this is easy to resolve. Not so on a single column.

 

[colin H]

I cant see any markings on the new rad , and the instructions only describe the wall mounting procedure .

I vaguely remember fitting one a while ago which came with a blanking plug , which had to be fitted somewhere to determine flow and return ( if this makes sense?) . There`s nothing like that with this one , though .

 

[terryplumb]

Without knowing the actual make / model / design of the rad one can not tell if it has to go a certain way up ,or if it has to have flow / return to specific ports. Like Dilalio said above , I too have fitted quite a few that have to be in a specific orientation ,but have also fitted some that don't. I would suggest you contact the manufacturer to ascertain their recommendations for your model. A picture of your rad posted on here may be useful.

 

[colin H]

Without knowing the actual make / model / design of the rad one can not tell if it has to go a certain way up ,or if it has to have flow / return to specific ports. Like Dilalio said above , I too have fitted quite a few that have to be in a specific orientation ,but have also fitted some that don't. I would suggest you contact the manufacturer to ascertain their recommendations for your model. A picture of your rad posted on here may be useful.

Thanks . Its a Milano Alpha from Best Heating . Ive just had a look at the website , and there`s a fitting guide on there (yes, I should have looked earlier!!) It recommends the use of a baffle , on the flow side - so I will need to find out which side it is after all . Good job I looked , as it doesnt mention this on the paper instructions or on the product description . I bet loads of folk have fitted them without the baffle !