Boiler (glow worm ultracom hxi 24) only turns on briefly and doesn't get past 60degs

dc197

Hello
Could I please ask for some advice about the above boiler, 8 years old, in a house we bought last week.
I turned the heating on this week to test it oit and although the boiler fires it only stays on for less than a minute. The temperature display rises to around 60, then it stops burning and the temperature drops. It repeats every few minutes. The rads only get warm, never hot.
I have tried the boiler with its max temp of 82 and with a more modest 50, same results, although the cycle is more frequent with the lower setting.

My last boiler stayed on for minutes on end and the rads got very hot. The new house's boiler seems odd.

The same things seems to happen when I demand an hour's DHW.

I have tried resetting, no effect. No fault code showing.

Any tips on what to try next it what I should expect to see?

Thanks

southcoastrgi

Faulty pump, no water in the system, a blockage

cyclonebri1

Sounds like a pump failure to me, would it kick in at all with low pressure SCR?

Pump need bleeding?

dc197

Thanks guys. I will check the pump, although it does seem to whir (quite loudly actually).

southcoastrgi

cyclonebri1 wrote: »

Sounds like a pump failure to me, would it kick in at all with low pressure SCR?

Yes because the boiler hasn't got a pressure switch

dc197

I tested out the hot water last night. It seems to behave a lot better: boiler gets up to max 82 degs, then the burn drops to a lower setting to keep the temp up there. Taps are nice and hot.
So I hope this means I can rule out a boiler problem.

Tell me, please, does the central heating pump also lift the water from the boiler through the hot water cyclinder? Because if so it would appear that the pump is OK.

Thanks

cyclonebri1

southcoastrgi wrote: »

Yes because the boiler hasn't got a pressure switch

Cheers fella, so it just shuts down on over temp?, as it would if the pump wasn't cooling?