Radiator on ground floor not heating up

[meanwhileinhell]

Hi all,

I have a radiator on our ground floor that never gets beyond luke warm. I live in a three storey Victorian end terrace and the problem radiator is on the front outside wall. The boiler is outside at the back in a boiler house. All of the other radiators in the house are on an inside wall.

There is a radiator in each of the two rooms on the top attic floor, which get roasting hot, even when only opened a quarter. The first floor radiators get good and hot too. on the ground floor there is only one radiator in the dining room (which is at the back of the house) and two in the living room (the front of the house) and one outside the living room in the hall.

Neither of the two radiators in the living room get overly hot, especially the one on the outside wall. The only time i have ever felt it roasting is when we removed the dining room one during decorating. The bizarre things is that i cant touch the lockshield valve for more than a second as its very hot, but the radiator isnt. The pump is set to about 1.5 bars (a plumber friend said that usually you set 0.5 bars per floor of house).

I have also tried to balance the radiators on each floor using the rule of top floor open a quarter, first floor open half, and ground fully open, but this doesn't change this particular radiator. I'm hesitant to increase the pressure anymore in case something blows.

 

[Blagard]

The bizarre things is that i cant touch the lockshield valve for more than a second as its very hot, but the radiator isnt. The pump is set to about 1.5 bars (a plumber friend said that usually you set 0.5 bars per floor of house).

If you have thermostatic rad valves fitted it could be they are the type that should only be fitted on the Flow. A very hot lockshield valve suggests to me that is on the Flow and with thermostatic valves I have mentioned it can't open with a reverse flow. Albeit a little may creep through allowing the hot to get to the lockshield. A faulty (stuck) thermostatic valve can have the same effect

The alternatives are airlocks or blockages.

You could try turning off the valves to the rad. Remove the rad, get a bucket and open each in turn to check active flow into the bucket.


When you get two very hot radiators that are clearly passing plenty, don't be afraid to turn them down by an 1/8 turn if even only open a quarter.

 

[meanwhileinhell]

Thanks for your reply Blagard.

None of the radiators in the house have thermostatic valves fitted (yet). What I find strange is that with the dining room radiator removed from the loop entirely, the radiator got as hot as you'd expect (incidentally, both of the radiators in the living room are the only double paneled radiators in the house and I would think are the newest). When this happened, the tops were as hot as the bottom, so am I right in thinking that this would suggest that there is no airlock, or sludging in that rad? And also rules out a blockage?

When we first bought the house, I bled all the radiators in the house, but the little square bleed valve on the front panel of this particular radiator snapped off. It didn't open so there is no leak. Plus this happened before we removed the dining room rad.

Could it be that there isn't enough water in the system to fully fill all the radiators, and only when one has been removed, does enough become available to heat the living room ones? Could this explain why the valves get hot, but the radiator doesn't? More to do with the heat traveling up the pipe, rather than the water within it (conduction rather than convection)?

 

[jackthom]

Are the pipes on both sides of the radiator and the bottom of the radiator itself hot? If that's the case it has to be almost full of air.