Radiator/ heating help!

[Andrew Massey]

Hi! Hoping someone might be able to give me so pointers.

I have an Ideal Classic FF350 boiler with Drayton thermostat and a Megaflo tank, 10 radiators throughout house. System works pretty much perfectly apart from one radiator. Itbis the biggest in house and on ground floor. It is cold at bottom, warmish at top. I have take it off and flushed though, put back on and same problem, maybe a bit warmer. I have just turned all rads off apart from problem rad and it has got much warmer. When i crank boiler to highest it is even warmer( but only to same level as all other rads on lowest temp)

I have read a lot of forums but i am totally out of ideas

Cheers

 

[PhoenixServices]

Sounds like the system needs balancing. Some where on the forum there is a thread for how to balance a system.

 

[ShaunCorbs]

Croppie's Balancing Thread.

 

[townfanjon]

Has it always been like this ?

 

[Andrew Massey]

It has for a couple of years but we have put up with it. The smae radiator has been flushed previously, when i did it today nothing came out really. One thing i have noticed is that one pipe is warm the other stone cold ?

 

[ShaunCorbs]

I would whip the rad off and check your getting good flow from both rad valves

 

[Andrew Massey]

Thanks Shaun

Thats a pic of the cold pipe valvenot sure if anything looks untoward

 

[ShaunCorbs]

That's closed I take it ?

Don't open it without a hose pipe connected

 

[Andrew Massey]

Sorry yes closed, rad back on at moment, will check flow nxt wkend.

Thanks for all your help

 

[Allgoode]

Hi,

Your supply pipe looks about 8mm, maybe 10mm diameter.

You might find that it is carrying as much heat through as possible to the rad which might have a higher heat displacement capacity than the pipe can carry for the water flow.

Depending on age of rad & how clean the system is it might pay to change rad to a lower water capacity & more efficient variant & also fit a magnetic filter to your system to take some of the crud out of it.

As mentioned above balancing the system will also help with even heat distribution in the system,

Thanks,

Andy

 

[Ric2013]

Andy, surely if the OP fits a lower water content radiator with the same heat output, and the pipe bore is restrictive, then the only advantage is that the radiator will warm up more quickly, but the flow will still be insufficient? So:

You might find that it is carrying as much heat through as possible to the rad which might have a higher heat displacement capacity than the pipe can carry for the water flow.

would still be the case?

 

[fixitflav]

Hi! Hoping someone might be able to give me so pointers.

I have an Ideal Classic FF350 boiler with Drayton thermostat and a Megaflo tank, 10 radiators throughout house. System works pretty much perfectly apart from one radiator. Itbis the biggest in house and on ground floor. It is cold at bottom, warmish at top. I have take it off and flushed though, put back on and same problem, maybe a bit warmer. I have just turned all rads off apart from problem rad and it has got much warmer. When i crank boiler to highest it is even warmer( but only to same level as all other rads on lowest temp)

I have read a lot of forums but i am totally out of ideas

Cheers

Do you have TRVs? If so you could try throttling down some or all of the rads other than the problem. Need to take off the thermostatic head to access the adjustment. Gives better control than throttling on iso valves, but could try that if you don't have TRVs.

 

[Ric2013]

Hi Fixitflav, what you say is true, and I agree that balancing on TRVs is better than using lockshields, but I think it's worth mentioning that most TRVs do not have an integral balance device and, if so, balancing on lockshields is the only option.
But I would agree that the first step is to get that system as balanced as possible before taking further measures.

 

[fixitflav]

Hi Fixitflav, what you say is true, and I agree that balancing on TRVs is better than using lockshields, but I think it's worth mentioning that most TRVs do not have an integral balance device and, if so, balancing on lockshields is the only option.
But I would agree that the first step is to get that system as balanced as possible before taking further measures.

My TRVs are Honeywell, and there's a plastic adjustment thingy with a screwdriver slot offset from the operating stem. I assumed all TRVs have it but clearly not if yours don't. Good luck!