Question regarding upgrading Radiators

[linuxbashshell]

Hi all
I'm looking to upgrade some regular old radiators ( 7 in total). The replacements are larger modern radiators. Two would be approximately 1600mm long by 600mm wide to hang on the wall. I've attached an image of old white radiator style and new radiator style (Grey) to give you idea of what I'm talking about.

I spoke to someone recently who told me you have to be careful when replacing smaller radiators with larger radiators as the boiler needs to be powerful enough to cope with the larger radiators. Is this the case?

And if this is important how would I calculate if my boiler is powerful enough to accommodate these larger radiators? Just slightly concerned the larger radiators may cause a problem if my boiler isn't powerful enough.

Any help is greatly appreciated. Thanks

 

[Terrywookfit]

Compare the sum of your radiators total output with the boiler output. Then compare it with the heat loss.

 

[Madrab]

Also be aware at how vertical tubular rads heat the space if your changing them all. Modern radiant tubular radiators aren't as effective at heating up larger spaces than convection type rads.

Cant count how many times I've been called back to change tall tubular rads to normal convection types, as they created too many cold spots.

 

[linuxbashshell]

Thanks for the feedback. How can I measure output of radiators?. I can find the boiler output but these radiators are 25 years old so no idea how to find out the spec. Thanks!