Hi all, I'm at a loss now and could really do with some suggestions please.
My boiler was working fine previously (should have left it alone!). I recently ran X400 around the system with a Magnacleanse attached to pick up the crud. I have drained down, flushed through, cleaned the F&E tank and refilled, adding x100.
Since then I noticed my boiler runs up for about 2 and a half minutes increasing the flow temperature by 5 to 10 degrees, then cuts off for about 2 and a half mins, before restarting, heating up a bit more and so on. (The cycling time makes sense as it apparently has a 5 minute anti cycling limit)
Once the flow reaches above 50 (close to the set flow temp), the cycling stops and it runs steadily. I presume this is due to the boiler modulating down?
I like to run it with a low set flow temperature of 55 (unless it gets really cold outside) gently heating the house up to 18 or 19.
When it cuts out, the status is 2967 "Temperature differential between flow temperature sensor and heat exchanger temperature limiter is too great"
I'm assuming I can eliminate it being a circulation issue in the central heating as I've the same happening when heating the water cylinder. I've bled all rads and made sure there's no air in the valves and the pump by cracking the nuts on the fittings slightly.
In an attempt to slow the heat increase down, I've set the boilers maximum output to 50%, but it makes no difference.
I've exhausted my limited knowledge and could really do with some ideas. Thanks in advance.
Worcester Bosch Life 8000 40KW regular Boiler -2 years old (not in warranty as supplied on the ECO scheme!)
Grundfoss Alpha 1 running in CP2 mode (though changing speeds makes no difference)
Open vented S Plan system
15 radiators, balanced with all but 2 having TRVs fitted. (same issue if wide open)
55 degree flow temp - 19 degree room temp
My boiler was working fine previously (should have left it alone!). I recently ran X400 around the system with a Magnacleanse attached to pick up the crud. I have drained down, flushed through, cleaned the F&E tank and refilled, adding x100.
Since then I noticed my boiler runs up for about 2 and a half minutes increasing the flow temperature by 5 to 10 degrees, then cuts off for about 2 and a half mins, before restarting, heating up a bit more and so on. (The cycling time makes sense as it apparently has a 5 minute anti cycling limit)
Once the flow reaches above 50 (close to the set flow temp), the cycling stops and it runs steadily. I presume this is due to the boiler modulating down?
I like to run it with a low set flow temperature of 55 (unless it gets really cold outside) gently heating the house up to 18 or 19.
When it cuts out, the status is 2967 "Temperature differential between flow temperature sensor and heat exchanger temperature limiter is too great"
I'm assuming I can eliminate it being a circulation issue in the central heating as I've the same happening when heating the water cylinder. I've bled all rads and made sure there's no air in the valves and the pump by cracking the nuts on the fittings slightly.
In an attempt to slow the heat increase down, I've set the boilers maximum output to 50%, but it makes no difference.
I've exhausted my limited knowledge and could really do with some ideas. Thanks in advance.
Worcester Bosch Life 8000 40KW regular Boiler -2 years old (not in warranty as supplied on the ECO scheme!)
Grundfoss Alpha 1 running in CP2 mode (though changing speeds makes no difference)
Open vented S Plan system
15 radiators, balanced with all but 2 having TRVs fitted. (same issue if wide open)
55 degree flow temp - 19 degree room temp
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