Halstead Hi Ace constantly firing up then lockout

abankerbutnotafatcat

Hi,

We inherited this boiler with our new house 18 months ago and it's always had a problem of going into lockout roughly every 5th time it fired up when we have to reset it - awkward if you're in the shower but cope-with-able.

Once, last winter, the resetting wouldn't work and after consulting the manual I found there is an additional button on the underside of the boiler and this sorted the issue out.

However, for the last couple of weeks the boiler seems to be constantly firing itself up when the heating is on. So rather than just firing up and keeping on going until the set temperature is reached it fires up for a few mins, then stops, then fires up again. All this means that it's frequently going into lockout, a cycle that is broken for a few hours by pressing the button on the underside but then starts again later.

We are due an annual service soon from our boiler service agreement provider (Southern Electric). Has anyone any advice on what we could do or what we need to ensure the boiler engineer does during the service to resolve this?

blackshirtuk

I believe that your problem may be due to a scaled up heat exchanger.

The boiler fires, heat the water in the exchanger, but the flow of water is reduced due to the scale, meaning too much heat goeas into the water. The water heat sensor detects that the water is too hot so shuts down the burner, and the cycle starts again.

After several ignitions in a short space of time it will lock out.

The only long term solution is to either descale the exchanger or replace it.

A short term fix could be to turn the required temperature down, this will reduce the power of the burner, meaning less heat goes into the water, so the heat sensor won't trip as quickly.

I am by no means an expert, but had the same boiler and problems, this is how it was explained to me.

I am sure a gasafe engineer will be along shortly to tell you not to listen me!

abankerbutnotafatcat

blackshirtuk wrote: »

I believe that your problem may be due to a scaled up heat exchanger.

The boiler fires, heat the water in the exchanger, but the flow of water is reduced due to the scale, meaning too much heat goeas into the water. The water heat sensor detects that the water is too hot so shuts down the burner, and the cycle starts again.

After several ignitions in a short space of time it will lock out.

The only long term solution is to either descale the exchanger or replace it.

A short term fix could be to turn the required temperature down, this will reduce the power of the burner, meaning less heat goes into the water, so the heat sensor won't trip as quickly.

I am by no means an expert, but had the same boiler and problems, this is how it was explained to me.

I am sure a gasafe engineer will be along shortly to tell you not to listen me!

Thank you. Do you or does anyone else know whether descaling the heat exchanger is something we could expect as part of a service or is it a quite involved task?

diywhynot

abankerbutnotafatcat wrote: »

Thank you. Do you or does anyone else know whether descaling the heat exchanger is something we could expect as part of a service or is it a quite involved task?

No, it isn't part of annual service (see the installation guide). Best let a RGI diagnose the problem. As it is a Halstead, start saving. Expensive parts.

unclebulgaria

blackshirtuk wrote: »

I am sure a gasafe engineer will be along shortly to tell you not to listen me!

Nah you got that about right but, it could be a few different issues.
If it hisses like a kettle when its lit and maybe even pops then its a scaled up heat exchanger. If its not hissing and popping check the circulation pump is running all the time, it may be partially jamming due to debris or failing electrically this will cause over heating. Have a listen to it with a screwdriver handle pressed into your ear and the driver end pressed against the pump body.
How long ago did you last have it serviced?
Its all guess work without standing in front of it but to be forewarned...

abankerbutnotafatcat

unclebulgaria wrote: »

Nah you got that about right but, it could be a few different issues.
If it hisses like a kettle when its lit and maybe even pops then its a scaled up heat exchanger. If its not hissing and popping check the circulation pump is running all the time, it may be partially jamming due to debris or failing electrically this will cause over heating. Have a listen to it with a screwdriver handle pressed into your ear and the driver end pressed against the pump body.
How long ago did you last have it serviced?
Its all guess work without standing in front of it but to be forewarned...

Thank you. It doesn´t hiss or pop so we´ll try the other option. It was last serviced a year ago hence the annual review being due in the next few weeks.

abankerbutnotafatcat

Update: we reduced the heat of the c/h on the boiler and it does seem to have worked, the burner is no longer constantly switching itself on and off. So thank you for that.