Boiler's hot water mode only not working.

[RafeDonson]

I've moved into a new flat, and before I report this as a maintenance issue, I thought I'd run it buy the folks here to see if they can figure out if it's a fault or just me being dense.

I have a Heatline C24 or C28 condense/combi boiler, and the domestic hot water mode doesn't seem to work. If I flip the switch to the tap logo on the right, no matter how much I run a hot water tap, it doesn't heat up the water, and the gas light doesn't come on.

The workaround I've found is to put it into hot water / central heating mode, whereas the light kicks on when I run the hot tap. I can put the thermostat down to zero or the on-boiler radiator temperature down to zero, in which case it functions using hot water only.

So am I missing something, or is the hot water function not working as it should?

 

[plumbingservices]

If it`s working on ch/hot water sounds like the diverter valve which switches over from heating/hot water is stuck in mid position, and won`t switch fully across to hot water only.It`s probably faulty and needs replacing or repairing.

 

[DaveHannigan]

Sounds like the switch faulty if hot water ok in CH/HW with room stat turned down. Report as fault I think

 

[plumbingservices]

Sounds like the switch faulty if hot water ok in CH/HW with room stat turned down. Report as fault I think

He never mentioned roomstat,it wouldn`t make any odds anyway if it`s turned down,the only way to get hot water is to switch to ch and hw which suggests that if he wants hot water he has to put on his heating also, which points to faulty diverter valve. In other words it is stuck in mid position giving both hot water and heating only.

 

[DaveHannigan]

The workaround I've found is to put it into hot water / central heating mode, whereas the light kicks on when I run the hot tap. I can put the thermostat down to zero or the on-boiler radiator temperature down to zero, in which case it functions using hot water only.

This would suggest room stat to zero and boiler stat to zero. In this state boiler will only respond to hot water demand, which it does. If the boiler then supplies heating when stats are turned up the diverter valve must be working ok,

 

[plumbingservices]

I understand that with heating stat turned down and boiler set to hot water/heating,he would get hot water and no heating but doesn`t this just prove that diverter is only moving to mid position i.e hot water/heating? Still suggests that motor not moving to hot water only position or is it me?

 

[DaveHannigan]

The diverter is not a mid position, combis work on hot water priority. If it had failed mid way then the hot water would be lukewarm at best and the radiators would start to warm up as the hot water was being used and the OP does state this to be happening.

 

[plumbingservices]

If diverter is not midway, how can you have hot water only or heating and hot water S`cuse me ignorance Dave

 

[DaveHannigan]

S'cused

 

[plumbingservices]

Answer the question then! I`m a plumber with a gas certificate, doin me best, have a heart.

 

[DaveHannigan]

Sorry I misread your answer.

On heating & hot water the boiler will work on central heating only with the diverter in the central heating position. On turning on a hot tap the boiler senses the flow in the domestic circuit and switches the boiler and diverter over to hot water only. Were you to leave the hot water tap running long enough. The heating would cool down.

 

[plumbingservices]

Nice try but complete Mumbo Jumbo mate, that`s complete twaddle, wot you sayin??

 

[Dan Robinson]

You do realise this is a combi boiler don't you?

 

[RafeDonson]

Uh oh - what have I started?

Either way, thanks for the advice - I've reported it, and if I'm in when it's repaired, I'll tell you what the fault was.

 

[DaveHannigan]

Nice try but complete Mumbo Jumbo mate, that`s complete twaddle, wot you sayin??

Oh dear, late sunday evening after all day on the pop, look it up in the morning when you're sober.