Think I have blocked pipes in my radiator circuit.

[stormyuk]

Hi,

I have been trying to get two radiators working for what seems like an age now. A bathroom one (upstairs) and the hallway one (downstairs).

I have a total of 5 radiators in my house, bathroom, bedroom 1 and bedroom 2 (all upstairs). A living room one and a hallway one (downstairs).

I fitted a thermostatic valve on both bedroom radiators about 2 years ago and that's all been fine. So I fitted one on the bathroom one about 6 or 8 months ago and since then, the radiator has never worked properly, it never gets any more than very slightly warm (and not much at that).

At the same time I replaced both old downstairs radiators for new Stelrad ones.

I thought originally that the TRV on the bathroom was faulty but couldnt explain the fact the hallway radiator used to be fine before the new one although it looked past its best hence the replacements.

So today I took both the suspect radiators off, flushed them through a number of times, some rubbish came out but they seemed to fill and flow ok under pressure from a garden hose so both radiators I think are fine.

But when we opened the valves on the radiators, the TRV on the inlet to the bathroom radiator dribbled, while the return valve flowed freely with water.

Same on the hallway radiator, the inlet valve (non-TRV) dribbled while the return valve flowed fine.

So we risked taking the TRV off although looking inside the valve seemed to operate fine. With the TRV off the pipe dripped, nothing more grrrrr.

So looks like I have blocked pipes. I drained down and flushed through the system a few times with the radiators back on, but noticed that water was not free flowing like it had been in the past when I had drained down.

The system is a thermal store btw. Open system with F/E tank above the main tank in the airing cupboard. 2 pumps, one to the conventional boiler to the tank and one to the radiator circuit to the tank.

So after my Dad kindly took a trip to B&Q while I was messing around for some Sentinel X400 (last hope now, before I either get someone to powerflush or some expert in).

So put that in and opened all the valves and lockshields fully with the pump on full speed after the tank was up to temp and same so far, 3 radiators blistering hot, the hallway and bathroom actually stone cold now.

I tried closing the 3 good radiators off for a while but no joy on that either, the other 2 just dont want to play.

Any one got any other ideas?

Thanks very much.

 

[seco services]

if you've only just put the x400 in leave it for a while it won't perform 100% in a few hours. can be left in system up till 4 weeks.

http://www.sentinel-solutions.net/en/heating/X400/questions

 

[stormyuk]

Yes, it says upto 4 weeks but is it likely to make much impact on a blockage, its not a complete blockage but it seems like it almost is.

 

[shambolic]

You will need to cut and section pipework to clear it as 400 will not clear a blockage.
I would first try at the manifold where the pipes join in (if 8mm) they are known to choke here!

 

[seco services]

you'd been better with x800

 

[stormyuk]

Hmm, looks like I will be leaving it broken then lol. No way I will be able to lift my floors and locate the blockage. Its laminate in the bathroom for a start.

Pipes to the hallway are behind my plasterboard so thats a no no too without ripping my house to shreds.

Its 10mm plastic.

Ah well.. bugger.

x800 seems to be for advised for use with powerflushing.

 

[seco services]

still can use it without a powerflusher. i use both sometimes without the flusher and its been successful. powerflushing is over rated.

 

[JPC]

i that case leave the x400 in for 4 weeks and see if it gets better.....then try x800 for 4 hrs / day...(with system running) and see if thats dislodges your blockage.....

if you are running on microbore, you will most probably have a manifold. the manifold can get clogged up with crap and stops flow

is it open vented ?...check your over flow is ok. connect a hose to a tap and then to the radiator valves that dont work...poss with help, open the rad valve, then the water to the hose...the mains water in the hose will push out any crap and hopefully overflow into the f and e and into the overflow......this method would struggle to remove lime build up will will move poss blockage in manifold

just some poss solutions

 

[malkie]

Why not try connecting a hose to the pipe that you say is just dribbling out and close the other rads and see if it can push any crap up and out the expansion,with it being 10mm it doesnt need much to stop the flow and it may move enough to allow circulation. There isnt a anti grav valve anywere is there its a long shot but you never know.

 

[JPC]

malkie...what a good idea!

 

[malkie]

Is that a hint of sarcasim Jamie,anyhow i tried this on a system that had a couple of cold rads and forced mains through the pipes and it forced enough to allow heat to get through,i still would let the x400 have a gom as well if this isnt a sucsess

 

[stormyuk]

Thanks for the suggestions guys, I will leave the X400 for a while then try the connecting a pipe trick.

Is it ok to pipe mains pressure water into my open system, yes it does have an expansion tank in the airing cupboard above the main tank. (where I loaded the X400, and of course inhibitor in the past.

I have no idea what the setup of the piping is or if there is a manifold etc.

I dont even know what an anti-grav valve is.

Here are pics of the main tank and header tank.

Mike

 

[stormyuk]

Oddly, since putting the X400 in at lunchtime and running the system continuously, both of the radiators are completely stone cold now, lol worse than before! Nice!!!!

I guess I probably made the blockage worse when I drained down again. Grrrr.

 

[stormyuk]

Hmmm..

Is it ok to try using mains pressure through the pipes, with them being 10mm plastic fittings or is that asking for trouble?

Also is it worth me trying to turn my central heating circulation pump around and pump the other way? Is it possible? Will it cause me more problems?

The pump is the one on the bottom right hand side of the picture. Its a 3 speed circulation pump.

I really don't want to have to demolish my house.

 

[Jonnyboy705]

Hi I'm John first of all have u left 1rad with out a trv on as a bypass rad also have fitted the trvs on the right end of the rad is try draining down heating sytem and get a foot pump onto the end of the blocked pipe u might have to make a fixing etc to fit them try pumping air into the blocked pipe hope tis helps