Possible blockage for one (or more) radiators - how safe is this?

[larkim]

One of our radiators singularly fails to heat up. The pipe to it is appropr= iately hot, but the rad never gets anything more than tepid. I've tried a = bit of balancing (trial and error rather than with a thermometer), but I'm = wondering whether there is some sort of blockage in that rad so want to try= a sledgehammer type approach.

The rad is on microbore.

If I were to turn off (either via the TRVs or valves on the non-trv'd rads = in the rest of the house), am I likely to do any damage to the pipework or = the boiler by just trying to force a flow through just one micro-bore radia= tor?

Firstly I'd want to see if it heated up, and then secondly (if it didn't he= at) I'd try opening the bleed valve to check that some pressure / flow is w= orking there.

Any thoughts?

Thanks!

Matt

[John Williamson]

appropriately hot, but the rad never gets anything more than tepid. I've tried a bit of balancing (trial and error rather than with a thermometer), but I'm wondering whether there is some sort of blockage in that rad so want to try a sledgehammer type approach.

the rest of the house), am I likely to do any damage to the pipework or the boiler by just trying to force a flow through just one micro-bore radiator?

I'd try opening the bleed valve to check that some pressure / flow is working there.

I'd have opened the bleed valve before doing anything else.

[larkim]

ropriately hot, but the rad never gets anything more than tepid. I've trie= d a bit of balancing (trial and error rather than with a thermometer), but = I'm wondering whether there is some sort of blockage in that rad so want to= try a sledgehammer type approach.

ads in the rest of the house), am I likely to do any damage to the pipework= or the boiler by just trying to force a flow through just one micro-bore r= adiator?

t heat) I'd try opening the bleed valve to check that some pressure / flow = is working there.

Done that, no significant flow. No air either.

[Phil L]

Just turn off all the other radiators and open this one fully, then create demand, no harm will come to your boiler if this is blocked as it will effectively be all rads off, IE no demand for heat. My bet is that it will heat up if it's just a circulatory problem, if not, it's either sludged up (in which case you can take it off and flush it through in the garden with a hosepipe) or one of the valves is knackered

[larkim]

That was my hope / expectation! Pipework around the house is a complete ho= tpotch of routes / "normal" bore / microbore and there are massively differ= ent thermal properties in different parts of the house - front is single sk= in brick, single glazed with suspended floors and poorly fitting (but aesth= etically pleasing!) floorboards, back is 1990s built, cavity wall, double g= lazed, solid floors with carpet covering. Wouldn't mind cool radiators if = it weren't for the fact that the ones at the front (cold) part are the trou= blesome ones!!

Cheers!

Matt

[Alan]

If you are able to remove the radiator thermoset you will find a metal pin stuck in the down position. Give it a sharp tap and an application of graphite powder.

Alan

[larkim]

Looked at that initially, the pin seems to be correctly placed and moves properly as it should.

Thanks

[Tim+]

Sometimes the pin moves freely but the valve jumper sticks to its seat. Again, a sharp rap with a hammer to the side of the valve body (not the pin) will sometimes release a stuck valve.

Tim