Really hope someone can help as I can't afford to tear any more hair out!
The problem
Boiler cuts out and comes back on every 55 seconds
4 (out of 8 ) downstairs rads are lukewarm at best
The situation
Large house with 16 rads, 8 upstairs 8 downstairs. System is about 25 years old including the boiler which is a gloworm (forget the model). Radiators upstairs work ok (not great) and downstairs there are 4 rads which are poor. The 4 poor rads are all connected with microbore all others are 15mm. 2 bypass, one to bathroom rad other direct back to boiler.
Work done so far
New two way port valve (hot water) installed.
Bypass valve installed (only service valve before, which was locked open)
Boiler serviced
Chemical flush, 6 downstairs rads removed and flushed with hose
Pump checked and is fine
Room thermostat is fine
After this there was still little or no improvement so I bought a power flushing machine and gave a it a good flush through, all rads seemed to work for 48 hours then the 4 bad ones went stone cold.
I have also balanced and rebalanced several times.
What now?
When I was doing the power flush I did suggest that if it still didn't work we could try replacing one rad to see if that helped but the client and myself are a little reticent to do this when one day a rad works and the next it doesn't....why did it work in the first place and now why doesn't it? The water ran clear on every rad when power flushing and also had flush buddy attached - there was no sludge left in the system and all other radiators work great now.
I have suggested all along that he could well need a new boiler, but not sure that would cure anything and the client likes the idea of ruling out cheap possibilities rather than try a $1700 (sorry no pound sign) new boiler installation. However we seem to be running out of ideas.
Also I know that microbore is pants but short of a replumb what else can be done?
I'm sure I've left out lots of info that people will need to help, so just ask.
Thanks
The problem
Boiler cuts out and comes back on every 55 seconds
4 (out of 8 ) downstairs rads are lukewarm at best
The situation
Large house with 16 rads, 8 upstairs 8 downstairs. System is about 25 years old including the boiler which is a gloworm (forget the model). Radiators upstairs work ok (not great) and downstairs there are 4 rads which are poor. The 4 poor rads are all connected with microbore all others are 15mm. 2 bypass, one to bathroom rad other direct back to boiler.
Work done so far
New two way port valve (hot water) installed.
Bypass valve installed (only service valve before, which was locked open)
Boiler serviced
Chemical flush, 6 downstairs rads removed and flushed with hose
Pump checked and is fine
Room thermostat is fine
After this there was still little or no improvement so I bought a power flushing machine and gave a it a good flush through, all rads seemed to work for 48 hours then the 4 bad ones went stone cold.
I have also balanced and rebalanced several times.
What now?
When I was doing the power flush I did suggest that if it still didn't work we could try replacing one rad to see if that helped but the client and myself are a little reticent to do this when one day a rad works and the next it doesn't....why did it work in the first place and now why doesn't it? The water ran clear on every rad when power flushing and also had flush buddy attached - there was no sludge left in the system and all other radiators work great now.
I have suggested all along that he could well need a new boiler, but not sure that would cure anything and the client likes the idea of ruling out cheap possibilities rather than try a $1700 (sorry no pound sign) new boiler installation. However we seem to be running out of ideas.
Also I know that microbore is pants but short of a replumb what else can be done?
I'm sure I've left out lots of info that people will need to help, so just ask.
Thanks
