I got back from holiday and found my central heating had
gone off in the middle of the snow

I have a Trianco 25/45 gas boiler. Holding the ignitor
in for about five minutes gets the pilot light on. Turning
the control on fires the boiler and the pump runs. After
about two minutes the boiler shuts down. I thought it
might be the overheat cut-out, but I can re-ignite it
without resetting the cut-out.

While the boiler was running for the couple of minutes
it ran the flow pipe didn't seem to be getting warm, so
I diagnosed a dead pump. Being 4:30pm on Easter
Saturday, and with snow building up, I rushed out
to get a replacement pump. Taking the old pump out
showed it to be full of crud, so that could have been
the/a problem. However, with the new pump in place
it hasn't fixed the problem. If I can manage to get
the pilot lit the boiler runs for maybe a minute before
turning itself off.

I had planned to have the boiler replaced this summer
anyway, so if it's a dead duck that just brings it forward.
Any suggestions meantime?

Thanks.

jgharston wrote in


I got back from holiday and found my central heating had
gone off in the middle of the snow

I have a Trianco 25/45 gas boiler. Holding the ignitor
in for about five minutes gets the pilot light on. Turning
the control on fires the boiler and the pump runs. After
about two minutes the boiler shuts down. I thought it
might be the overheat cut-out, but I can re-ignite it
without resetting the cut-out.

While the boiler was running for the couple of minutes
it ran the flow pipe didn't seem to be getting warm, so
I diagnosed a dead pump. Being 4:30pm on Easter
Saturday, and with snow building up, I rushed out
to get a replacement pump. Taking the old pump out
showed it to be full of crud, so that could have been
the/a problem. However, with the new pump in place
it hasn't fixed the problem. If I can manage to get
the pilot lit the boiler runs for maybe a minute before
turning itself off.

I had planned to have the boiler replaced this summer
anyway, so if it's a dead duck that just brings it forward.
Any suggestions meantime?

Diverter valve? The valve that sends water to either hot tank or central
heating. If it fails, you get symptoms much as described.

Many valves have an easily replaceable motor - cheaper than replacing the
whole thing though the crud that filled the pump may also have done for the
valve itself.

--
PeterMcC
If you feel that any of the above is incorrect,
inappropriate or offensive in any way,
please ignore it and accept my apologies.

PeterMcC wrote:
I have a Trianco 25/45 gas boiler. Holding the ignitor

Diverter valve? The valve that sends water to either hot tank or central
heating. If it fails, you get symptoms much as described.

It's an on/off valve as http://mdfs.net/Docs/Plumbing/Heating.gif
so if the valve if stuck the heating water would still flow through
the hot water tank heating coil, just as though I'd selected
'HW only'. The HWC is about six months old, so I'd be surprised
if that had failed.

With the boiler off and the pump on, pressing an ear to the
pipework suggests water is flowing.

--
JGH

jgharston wrote in


PeterMcC wrote:
I have a Trianco 25/45 gas boiler. Holding the ignitor

Diverter valve? The valve that sends water to either hot tank or
central heating. If it fails, you get symptoms much as described.

It's an on/off valve as http://mdfs.net/Docs/Plumbing/Heating.gif
so if the valve if stuck the heating water would still flow through
the hot water tank heating coil, just as though I'd selected
'HW only'. The HWC is about six months old, so I'd be surprised
if that had failed.

With the boiler off and the pump on, pressing an ear to the
pipework suggests water is flowing.

There is a feedback cable from the valve to the boiler control - if the
valve has failed, water may still flow through it but it may be sending to
the control to shut down.

--
PeterMcC
If you feel that any of the above is incorrect,
inappropriate or offensive in any way,
please ignore it and accept my apologies.