Radiators... Talk to me - Please

Gimpymoo · 23 Jan 2017 at 18:35

What does one need to look for when buying a radiator?

More fins the better?

Thanks.

Dis86 · 23 Jan 2017 at 18:38

Are the pipes fastened in to the wall? How big is the room? Any aesthetic considerations?

koolpc · 23 Jan 2017 at 18:53

http://www.gasboilerforums.com/radiators.html

http://www.bestheating.com/info/blog/2016-bestheating-radiator-buying-guide/

FerretBoy · 23 Jan 2017 at 19:16

Check out the BTU rating and double check the Delta they used to calculate it, they like to cheat.

koolpc · 23 Jan 2017 at 20:19

Try BTU at different sites on the net to get an average reading. Thats what i did.

Gimpymoo · 23 Jan 2017 at 20:38

Dis86 said:
Are the pipes fastened in to the wall? How big is the room? Any aesthetic considerations?

Pipes are coming up from the floor so will be replacing like for like size wise.

Replacing very very very old single panel radiators.

Will post sizes later but they are very wide. Is a Victorian semi, front and rear living rooms with high ceilings.

Assuming I know the BTU values etc, what design of rad is most efficient?

Are vertical radiators efficient?

Also, if mounting a radiator ABOVE french doors, is this even a sensible option? Physics tells me not but you never know

I thought new rad designs pushed warm air through the top and bottom?

Bobmunkhouse · 23 Jan 2017 at 22:12

If current radiators are really old it will all be Imperial so none of the pipes will match the metric size radiators but I'm sure if your ok at plumbing you can sort...

Gimpymoo · 23 Jan 2017 at 22:30

The required BTU for the back room is about 7500 BTU.

2 external walls.
2.6m window space

That limits my rad choice unless I want to have 2 radiators.

Hedge · 23 Jan 2017 at 22:30

Ive replaced a few old radiators with new and just used extensions to make up the difference in sizes. I appreciate its not ideal but they look fine for now. It's usually about a 60mm difference.

In fact I'm replacing my hallway single panel with a new double one this week. Again I'm just using old valves and extension piece.

Saves ripping up my hallway flooring anyway!

SPG · 23 Jan 2017 at 23:34

Whatever the calculators say double it,

Stelrad or Barlow are the makes to go for and get your plumber to balance the system properly and forget about all this TRV nonsense everyone has fallen for.

robj20 · 24 Jan 2017 at 07:34

FerretBoy said:
Check out the BTU rating and double check the Delta they used to calculate it, they like to cheat.

Its not really cheating i'm pretty sure they all calculate to T50c, which in my opinion is too high for a condensing boiler. I'm sizing mine to T35C will ensure the boiler is always able to run in condensing mode.

Psycho Sonny · 24 Jan 2017 at 09:37

SPG said:
Whatever the calculators say double it,

Stelrad or Barlow are the makes to go for and get your plumber to balance the system properly and forget about all this TRV nonsense everyone has fallen for.

What exactly does balancing the system involve and it's purpose?

I've been learning bits and pieces about central heating and this is something I've not quite gotten into my head yet heard it mentioned several times.

robj20 · 24 Jan 2017 at 09:50

Psycho Sonny said:
What exactly does balancing the system involve and it's purpose?

I've been learning bits and pieces about central heating and this is something I've not quite gotten into my head yet heard it mentioned several times.

Not all radiators will get the same flow, due to pipe length and any bends. So you use the valves to allow the flow on the faster radiators.

An easy way to do it is each time you turn the heating on fine the radiator that gets hot first, turn the valve down a bit.
Keep doing this until they all warm up about the same time.

It's best to balance using the TRV valve settings, you need to take the head off to access this and usually need a special tool. Using the lockshield works but it's a pain if you ever need to remove the rad in the future.

Balancing isn't as big an issue these days with trvs anyway as each room warns up the TRV shuts down the flow and other radiators get a boost in flow.

Psycho Sonny · 24 Jan 2017 at 10:28

robj20 said:
Not all radiators will get the same flow, due to pipe length and any bends. So you use the valves to allow the flow on the faster radiators.

An easy way to do it is each time you turn the heating on fine the radiator that gets hot first, turn the valve down a bit.
Keep doing this until they all warm up about the same time.

It's best to balance using the TRV valve settings, you need to take the head off to access this and usually need a special tool. Using the lockshield works but it's a pain if you ever need to remove the rad in the future.

Balancing isn't as big an issue these days with trvs anyway as each room warns up the TRV shuts down the flow and other radiators get a boost in flow.

I have all of mine on max, would this cause any issues?

robj20 · 24 Jan 2017 at 11:24

If your rooms are warming up to your satisfaction then no.

roadie · 25 Jan 2017 at 13:50

I'm in the process of replacing mostly 1970s single panel radiators with new type 11 radiators of similar dimensions. They should kick out a lot more heat...

robj20 · 25 Jan 2017 at 14:17

roadie said:
I'm in the process of replacing mostly 1970s single panel radiators with new type 11 radiators of similar dimensions. They should kick out a lot more heat...

To keep your condensing boiler happy maybe even go bigger.
In one room I have gone from a 600x1400 (approx) type 10 to a 600x1800 type 21. Bigger the better with modern boilers.

Felix · 25 Jan 2017 at 14:22

It appears BTU calculating is a black art! No website says the same!

robj20 · 25 Jan 2017 at 14:48

Felix said:
It appears BTU calculating is a black art! No website says the same!

http://www.homesupply.co.uk/radiator_output_calculator.php

That one is well regarded as being pretty accurate.

Felix · 25 Jan 2017 at 15:12

robj20 said:
http://www.homesupply.co.uk/radiator_output_calculator.php

That one is well regarded as being pretty accurate.

That's give the lowest out of all the BTU calculators I have tried, I've basically taken a value from each one and gone for average and gone for the nearest radiator size above that BTU. I'd rather oversized than under!