Looking at getting a bigger radiator, anything i need to know?

Hi, we live in a house that’s 3 years old, the first winter we got the impression that the radiators in the living room didn't seem enough to heat the room properly as the rest of the house is always really warm but the living room is always pretty cold.

There are 2 radiators in the living room and was maybe thinking or replacing 1 with a bigger radiator to get that room warmer.

We did mention this to the housing developer at the time, we also said is there a way of knowing if the walls have been sufficiently been filled with insulation which they said they have no way of checking but they would have been.

As for the radiators they said they do meet the specs for the room and in their opinion the radiators should be enough to warm the room.

I guess that’s hard to challenge as i guess technically they do heat the room as it would be much colder if they were off but in our opinion they don't heat the room to the same standard all the other radiators in the house do.

The living room we have big French doors and skylight windows so this probably lets a lot of cold in i would guess. i don’t know if that’s something the developer hasn't really taken into consideration when deciding what heating they would put in as the radiators in the living room aren’t exactly that big, each is only 70cm wide and 60cm high.

It's been too long to challenge the developer now anyway.

I mainly just need to know am i able to just buy any bigger radiator or are there different fitting radiators or types?

I will be getting someone qualified to do it or cause.

I guess it would be good if someone could also give me an idea how much I’d expect to pay someone to replace 1 radiator? so i have an idea and not getting ripped off if anyone has an idea?

Thanks

James

is your old radiator fully hot all over? Top, bottom, middle and sides?

Is the Flow pipe "too hot to hold?" And is the return pipe "too hot to hold for long?"

Is the room stat in this room?

Does the radiator have a TRV? What is it set to?

Is this room open plan, or is the door left open so warm air can escape?

What temperature is your boiler set to?

You are right, builders frequently fit rads that are too small. Perhaps they are very hardy, or perhaps the housebuilders want to maximise their profiits by fitting rads that are small and cheap. Two radiators each 70cm wide and 60cm high sound very small unless it is a small room. My bathroom has one that size (it is ample).

Do the radiator pipes come out of a concrete floor (i.e. cannot readily be moved)?

Just put a bigger rad in with a thermostat on it.

Expect to pay £80-100 + rad.

Hi thanks for both replies, can you get radiators that have their own individual thermostats on? and would that tell the boiler to just send how water to that 1 radiator that’s asking for it or the whole system?

At the moment the TRV's are set to full for both radiators.

The boiler is set to 72c for radiators.

The radiators are also hot all over and are very hot to touch so are working to their capabilities, i think it’s just the size of the room and amount of windows in the room just makes it all colder than what it should be.

I don't really want to set any temps higher as the rest of the house is really warm and don't want the rest of the house unbearably hot compared to the living room.

The main thermostat is in the hall.

Modern boiler should modulate i.e. turn up/down automatically to suit demand, it does this by measuring the temperature of the return water, so any radiator returning hot water can turn down the boiler, and so first job is to ensure all radiators as set correctly so the cold room radiators can run as hot as possible for as long as possible.

We have two controls, the lock shield valve, and the thermostatic radiator valve, (TRV) in the main the lock shield controls speed and the TRV room temperature and when target temperature is approached the radiator should cool, the TRV controls room temperature not the wall thermostat (in the main) the wall thermostat should never turn off in the winter, it is only there to stop cycling.

There are fan assistance units that should boost the radiator output, but never tried them, only tried proper fan assisted radiators, but most likely is the boiler is shutting down early because the other radiators are not set.

It may be the radiator is too small, however I suspect more down to balance. In theory one should remove all TRV heads so the radiators have no temperature control, and shut down the lock shield valve until 15°C temperature drop across each radiator, that requires a differential thermometer, which most don't have, so I close the lock shield fully, then open 1/4 turn at a time until the feed gets warm, then stop, once all roughly set, then I adjust by opening cool rooms at little more, not how is should be done but it seems to work.