Can anyone tell me if house radiators are generally all connected in series by one pipe, so if you take a rad out then the central heating won’t work? Or are there secondary pipes so you can still run the system with a rad taken out?

Reason I ask is that I had to take a radiator off a wall for some plastering. I can’t put it back on for a few days because the plaster won’t be dry and I’d need to re-mount the rack for the rad. Does this mean nae central heating till then, or am I going to be OK to turn it back on because the hot water will be routed round the missing rad?

Sry for the simple question – the central heating system is new if that makes a difference.

Pretty sure from my investigations under the house, that ours are in parallel. I suppose they would be seeing as we have wee thermo valve things on them.

Your house may differ though.

p.s how is life btw?

just make sure both rad valves are turned off and fill the system pressure back up if need be around 1.5 bar, both the rad pipes come off the circulating pipes flow/return, unless you have one pipe system which i doubt as you say the system is new you will be fine, also if you drained the system down completely make sure to add inhibitor after putting the old rad back on..

We did this a while back so memory of exactly what we did is fading. If your rad I’d off then there should be 2 pipes sticking up (vertically) which lead to the main circuit under the floor. If you put cap ends on the two sticking up pipes then you should be able to turn the rads on again. Pretty sure of you don’t cap it you will end up with a flooded room.

There’s a feed pipe and a return pipe to each rad, so you can close the valves to the rad, remove it and carry on with the job, not affecting the rest of the house.

Thks lads – central heating toastiness now back on.

The real answer is it depends on how your heating was plumbed.

i ve not yet seen a single pipe system although they may be out there..

Flow & Return (most common, more efficient):

Single Pipe (some older systems):

You often see single pipe systems in older schools/large office buildings etc. One big pipe with both ends of the radiator plumbed into it.

As the diagram shows. You can still use your heating with either type of pipe system. But you already know that cus you’re nice and toasty. 🙂 Incidentally, the item you refer to as the “rack” for mounting the rad to the wall? There should be at least 2, sometimes more on very long rads. They are simply called “radiator brackets.” I’d hate for your plumber to sneer should you call them racks in his presence.
Oh, and the item listed as “pressure relief valve” on the top diagram is incorrectly labelled. It is in fact a bypass. The pressure relief valve would be on the boiler and only if the system was pressurized as apposed to gravity fed.

i ve not yet seen a single pipe system although they may be out there..

Nope, I’ve never seen one either.

And I’ve seen a fair few central hearing systems 🙂

If you’ve ever been in an old school or public building, you’ve probably seen a single pipe system without realizing it.

I only did domestic when I was plumbing.

But I have been in a school (but I tried my hardest to avoid it 🙂 )

Plenty single pipe systems in house. Unless you can see the tees it can be hard to distinguish sometimes

totalshell – Member
i ve not yet seen a single pipe system although they may be out there..

POSTED 1 HOUR AGO #

Pretty much all of the old 1960’s leech houses (come through the door, floor to ceiling staircase with exposed staircase in kitchen) are one pipe systems, it’s just that most of them have a bypass under the floor* too. There’s not many that use the rad as part of the loop, with no bypass underneath.

The installers back in the day usually nipped the pipe here to balance the system.

The old Leech houses often have a valve to stop the upstairs rads heating from the gravity circs too.

There’s no need for a bypass on a one pipe system. As there are no TRV’s on the rads, circulation can’t easily be halted and only an idiot would put a bypass where it’s inaccessible in any case. Should it become inoperable at a later date, the whole place would need ripping apart in order to find it. Unless of course the bloke who put it in was around to tell you where it was. Unlikely!

Think by pass is not the right word. The pipe that goes beneath the radiators is just part of the circuit. Some of the water does “by-pass” the radiator but is is not a by-pass in the usual sense.

You can have TRV’s on one pipe systems too.

This could go on and on 🙂

There are two types of one pipe system. Those that loop the house and flow through the rads individually, if you turn off any radiator, then circulation is lost, and those that loop round the house and feeding both legs of the rad. The section of pipe between the flow and return of each rad has to be restricted quite often, so that the heat will pass through the rad, rather than just taking the easy route. Agreed, this is not a bypass, I was hoping to assists the guys above who have never seen one.

Just to be a further pedant, a bypass in the traditional sense has nothing to do with TRV’s.

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