halstead finest platinum hot water switches off after 30secs

[TIMSKIER]

I have a Halstead Finest Platinum Combi boiler. The central heating works ok but when turning the hot water on the water heats for about 30 seconds and then goes cold with the reset light turning to Red. I have had 6 call outs by an engineer and nothing has been resolved. The engineer has replaced the following items: Diverter Valve, pump and the central heating sensor but I'm still left with the initial fault. Any ideas what the fault is?

 

[transam]

I am not that familiar with this model , but it sounds like your boiler is going to overheat lock out on h.w ??? I assume that u do not have a seperate overheat reset button ?????

 

[petit_pablo]

Plate heat exchanger

 

[harold5]

what fault code are you getting on the LEDs

 

[TIMSKIER]

I am not that familiar with this model , but it sounds like your boiler is going to overheat lock out on h.w ??? I assume that u do not have a seperate overheat reset button ?????

Thanks for the info. Checking the diagnostic LED's it appears that the overheat thermostat is activated.

 

[TIMSKIER]

what fault code are you getting on the LEDs

.

Thanks, The over heat thermostat is activated.

 

[TIMSKIER]

Plate heat exchanger

.

Thanks for the info. If it is this, what is the cost for repair? It's strange that the central heating is fine.

 

[transam]

Plate heat exchanger

.

Thanks for the info. If it is this, what is the cost for repair? It's strange that the central heating is fine.

When your boiler is in the h.w mode , the heated water from the boiler is pumped around a plate exc , e.g it short circuits around the boiler , as petit pablo indicates if your h.w plate exc is restricted , than there is a possibility of the boiler over heating , also when your boiler is in the h.w mode it is (probably) under the control of a seperate stat/ sensor (thermistor), these can be checked by your rgi .

 

[TIMSKIER]

Plate heat exchanger

.

Thanks for the info. If it is this, what is the cost for repair? It's strange that the central heating is fine.

When your boiler is in the h.w mode , the heated water from the boiler is pumped around a plate exc , e.g it short circuits around the boiler , as petit pablo indicates if your h.w plate exc is restricted , than there is a possibility of the boiler over heating , also when your boiler is in the h.w mode it is (probably) under the control of a seperate stat/ sensor (thermistor), these can be checked by your rgi .

Thanks again, this does make sense.

 

[Agile]

They dont have to be replaced.

We generally clean them but where possible bring a ready cleaned one for a quick changeover on site. In out local area we charge £136.

They get blocked by dirt from the radiators. If its taken several years to get blocked this time then it would be about the same length of time before it blocks again.

The non invasive test is to measure the flow and return temperatures at the plate. It should normally be about 15-20°. Much more and its getting blocked or already blocked.

Fitting a magnetic filter or even a gauze strainer will usually trap most of the dirt before the boiler but then they have to be regularly cleaned.

Tony