mysterious airlock and other problems

natnifnolnacs

Hi, I'm looking for a bit of advice! 2 story house(1970's), 9 rads (all old, no trv's). crappy microbore pipes, tank fed system. The circulation pump was replaced 6 months ago (although I've been told it isn't a great pump)I've had a plumber out who power flushed the system and fitted a balancing valve to the cylinder. This now means the rads that were working are fantastic...but it hasn't fixed the original problem!

I have a rad downstairs which gets barely warm....it's enough to take the chill of the rad but doesn't actually heat up. I have another rad upstairs which used to heat up, but now doesn't (there is some heat to the pipes but doesn't translate to the rad itself), and I have another rad that works brilliantly but is constantly airlocking. I have to bleed it every 48 hours.

Where do I start?! Get a better pump? new rads? Burn the house?!!The plumber balanced the system when he was here but I'm going to shut off some rads completely today and see if it makes any difference. When he was here he did get a bit (only a bit) of heat to both rads and I'm fairly sure this was by having other rads turned off... Any help would be greatly appreciated!!

Dtp1979

natnifnolnacs wrote: »

Hi, I'm looking for a bit of advice! 2 story house(1970's), 9 rads (all old, no trv's). crappy microbore pipes, tank fed system. The circulation pump was replaced 6 months ago (although I've been told it isn't a great pump)I've had a plumber out who power flushed the system and fitted a balancing valve to the cylinder. This now means the rads that were working are fantastic...but it hasn't fixed the original problem!

I have a rad downstairs which gets barely warm....it's enough to take the chill of the rad but doesn't actually heat up. I have another rad upstairs which used to heat up, but now doesn't (there is some heat to the pipes but doesn't translate to the rad itself), and I have another rad that works brilliantly but is constantly airlocking. I have to bleed it every 48 hours.

Where do I start?! Get a better pump? new rads? Burn the house?!!The plumber balanced the system when he was here but I'm going to shut off some rads completely today and see if it makes any difference. When he was here he did get a bit (only a bit) of heat to both rads and I'm fairly sure this was by having other rads turned off... Any help would be greatly appreciated!!

How many rads?
How long did he take flushing the system?
Any idea what machine he used?
Did he put chemical cleaner in a few days before the flush?
And what brand of chemical was used?

natnifnolnacs

Dtp1979 wrote: »

How many rads?
How long did he take flushing the system?
Any idea what machine he used?

9 rads I think. He was here all day, probably 5 hours doing the flush. No idea of the machine. I'm confident he did what he was supposed to do, the thing now is what to do next?I'm happy to tackle most problems myself but don't want to go replacing radiators for no reason, or buying a new (better) pump and it not make a difference.

Dtp1979

natnifnolnacs wrote: »

9 rads I think. He was here all day, probably 5 hours doing the flush. No idea of the machine. I'm confident he did what he was supposed to do, the thing now is what to do next?I'm happy to tackle most problems myself but don't want to go replacing radiators for no reason, or buying a new (better) pump and it not make a difference.

Not being smart but your not to know if he used a good machine or bad machine.
He could have used cheap chemical.
What chemical was used?
Did he use magnets with his machine?

natnifnolnacs

Dtp1979 wrote: »

Not being smart but your not to know if he used a good machine or bad machine.
He could have used cheap chemical.
What chemical was used?
Did he use magnets with his machine?

If I knew all of that I probably wouldn't have needed a plumber in the first place:D

I have no idea but he flushed the system through several times, and brought me out to show it running clear compared to what I had seen a few hours previous.

If we can assume he flushed the system properly, what do I look at next? The pump?

Dtp1979

natnifnolnacs wrote: »

If I knew all of that I probably wouldn't have needed a plumber in the first place:D

I have no idea but he flushed the system through several times, and brought me out to show it running clear compared to what I had seen a few hours previous.

If we can assume he flushed the system properly, what do I look at next? The pump?

If it was flushed properly then maybe the pump. Maybe airlocks, maybe kinked pipes.
The only reason I'm focusing on the flush is because they'res chemicals you can buy for 6 euro or 35 euro. Needless to say you get what you pay for. Same with cheap machines. It sounds to me like sludge because your plumber has tried balancing and so on

natnifnolnacs

Dtp1979 wrote: »

If it was flushed properly then maybe the pump. Maybe airlocks, maybe kinked pipes.
The only reason I'm focusing on the flush is because they'res chemicals you can buy for 6 euro or 35 euro. Needless to say you get what you pay for. Same with cheap machines. It sounds to me like sludge because your plumber has tried balancing and so on

Thanks for the input. I get what you mean alright, and I guess you could be right but I reckon he did what he was supposed to do. Also the fact that there was a bit (not much) heat to both rads when he was starting to balance the system means that with more flow, they are getting something.

I think I'm going to risk a new better pump and see what that brings.

If that doesn't work, I'll probably remove the offending rads to make sure they are cleaned properly...after that I'm not sure!

Wearb

natnifnolnacs wrote: »

Where do I start?! Get a better pump? new rads? Burn the house?!!The plumber balanced the system when he was here but I'm going to shut off some rads completely today and see if it makes any difference. When he was here he did get a bit (only a bit) of heat to both rads and I'm fairly sure this was by having other rads turned off... Any help would be greatly appreciated!!

Did that make any difference?

If it did, then maybe a stronger pump. If not, a stronger pump is unlikely to sort it.