Hot water cutting out on combi boiler

[Stehuggey]

Hello all I've got a combi boiler and when I run the hot tap the boiler fires up for about 20 seconds then cuts out for about the same time and basically just running hot and cold not funny if you are in the shower ha ha . Any ideas what could be problem. Oh the heating is working ok. Thanks

 

[townfanjon]

Is it all hot taps or just the shower ?
What is the boiler ?

 

[AMGasServices]

Id say it’s an issue with the shower.

 

[Stehuggey]

Is it all hot taps or just the shower ?
What is the boiler ?

It's all hot water and it's a ace high halstead

 

[townfanjon]

It's all hot water and it's a ace high halstead

Job for a gas safe man then , sorry .

 

[AMGasServices]

The hot water is probably going down the central heating side. Does it fire up in hot water ?

If so check the central heating pipes see if they are heating up ?

 

[Stehuggey]

Job for a gas safe man then , sorry .

Ok cheers

 

[Stehuggey]

The hot water is probably going down the central heating side. Does it fire up in hot water ?

If so check the central heating pipes see if they are heating up ?

Yes it does fire up in hot water but cuts out after about 20 seconds so water starts running cold then kicks back in again

 

[Sparkgap]

If your flow rate is okay it could be the flow switch on the boiler. Get a gas safe bod to have a look.