Dafoss controlling an Ideal Classic Problem

[Nic]

Hi, I'd be grateful for ANY advice please!

We've not been in our house long and have had the system drained once or twice to replace leaky radiator valves. We had air in the system and the pump made a noise until the air worked its way out. We've also had one or two rads off to decorate.

Here's the technical bit:

Ideal Classic LXFF & FF Fanned Flue Gas Boiler controlled by a Dafoss FP715 control panel.

Problem:

Both heating and hotwater are timed to work twice a day but our boiler fires up throughout the day regardless. It has been firing up more frequently recently - it goes off and on all day long now and our water pump seems to be permantly on. Its like the system is trying to keep our hot water hot all day long. Is this right?

A friend as the same boiler but it only works during the 'timed' periods. Have we got a faulty Dafoss controller? Or is it our pump that is knackered? I am assuming that the boiler is only doing what the controller tells it to do...so guess it must be the controller but I'm not an expert!

I don't know if this is connected but our wall thermostat in the hallway 'clicks' at 10c - this doesn't seem right either. Is it connected to our problem?

Hope this is enough detail! Sorry if it is too much!
Many thanks, Nic

 

[oilman]

Your pump works so it's not knackered. The controller may be faulty, but the most likely problem is the 3-port valve (or 2-port if you have them)

What make valve have you got? If it's a Danfoss HSA3, or HPA2, (and you can't diagnose the fault) change the head, they fail often

 

[Nic]

Thank you for your reply. I've got two HPA2 Port Valves (white boxes). Sorry for my ignorance but when you say replace the head do you mean replace these valves (white boxes)?
Many thanks, Nic

 

[ollski]

Yes that's what he means..the heads are the valve actuators. It sounds like it is your hot water one that is faulty.

 

[Nic]

Just wanted to thank you both for yur advice. It turned out that one valve motor wasn't working and the other wasn't closing the valve properly either so I replaced both. The gas bill was huge when it arrived. I guess the boiler has been working overtime for many months! But its all working like a dream now! Thank you again!