Can anyone help me with my Myson Apollo 50Si boiler?

[ormus]

I have been experiencing difficulties with my Myson Apollo 50Si boiler recently which are more than a little mysterious. If anyone is able to offer some help, I would be most grateful.

When the system is cold, the boiler starts normally and will run continuously for approximately half an hour, heating all of the radiators to quite a high temperature. It then switches itself off, and will not start until the radiators are cold again. When the boiler switches itself off, it is not possible to switch it on again by turning the thermostat to a higher setting.

 

[namsag]

Might be the motor in motorised valve on its way out and breaking down under use.
Does the fan run
Does the pump also stop running or carry on
Is it just the heating or heating and hotwater that plays up

 

[Agile]

So many questions!

But to diagnose a fault thats whats needed, lotsof information!

Even when its known its not clear what the OP is going to be able to do about it. You dont push a button to repair a fault. They need new parts or and adjustment of the settings and usually both.

Tony

 

[libby lou lou]

Your drunk to night

 

[ormus]

Hello folks,

Many thanks for your replies, I will try to determine the answers to these questions in the next few days! For now I also have a wood burning stove so at least I'm not freezing to death...

 

[markymark1234567]

Probably the high/ low / limit thermostats faulty changed loads of these for the fault your describing

 

[ormus]

So, some observations

When the boiler turns itself off, the fan does not run. The pump keeps running. This affects both heating and hot water. I've looked at the wiring diagram, so I have some ideas of what could need replacing, but I will keep them to myself for the moment...

 

[ormus]

Anyone prepared to chip in? My thinking is that it might be worth replacing the hi-low and limit thermostats and seeing if that helps...

 

[Agile]

Thats odd! Was that your original thoughts because Mark has already suggested that.

I dont just blindly replace parts!

I use measurements to identify exactly whats wrong.

But it does sound like those stats and they are not so expensive.

Tony

 

[ormus]

Hello Tony,

I understand what you're trying to get across. Really it's my mother who is trying to avoid parting with too much money. Yes, my thoughts are informed by the suggestion of Mark, as well as by looking at the schematic for the boiler. Thankfully ideas are not yet subject to copyright law! Thanks to all for your help, I have now tried to convey this information to my mother.

A.

 

[Agile]

This is now quite an old boiler although the efficiency is quite good.

Overdue for replacement.

Tony