Just a Dribble...

[Chris_E_Dub]

We had a Halstead Ace High Comi installed just over a year ago in an upstairs bedroom and have had absolutely no problems with it whatsoever. But recently there are two things which ahve occurred on which I wouold like some advice.

• Firstly, when the boiler clicks on to start heating, whether for general water, or heating, for the duration of the time it is on, a regular 'sparking' sound can be heard coming from near the top of the unit. Halstead sent an engineer out to look at it, but they said there was no problem – this has never affected performance, but I would just like to set my mind at rest!

• More recently (and I think, unconnected) the water from the hot bath tap (in room next to where boiler is located) has intially started runnning fine, but then reduces gradually to a sorry dribble. The sink next to the bath is fine, however. My old man seems to think this is due to an airlock, but he didn't know it was a combi boiler – surely it isn't safe to remedy this (i.e. force air back through the system) in the normal way, in the case of it being a combi?

Any help very much appreciated!

 

[oilman]

If it's a combi, airlocks will not be a problem. The hot tap sounds like it is slowing down as it heats up. Does it do this if it is fully open? Try turning the bioler off and then running the hot tap so that cold water runs out. Does the flow gradually slow down then?

 

[MANDATE]

The hot water is from the same source as the cold water, the incoming main supply, ie cold goes to cold tap and cold goes to hot tap via the boiler making it hot. So you cannot get an air lock on the hot water side and you cannot force air back against the mains pressure.
You only force air back in systems where there is a water tank and a expansion/overflow pipe and you use mains pressure to achieve this.

 

[Chris_E_Dub]

I turned off the boiler, and the water flow was exactly the same, just ran to a dribble again. Surely this must be something more mechanical to do with the tap itself then?

 

[oilman]

How fast does it take before it dribbles? There is probably a blockage in the pipe, so when the tap is off, pressure can uild up. When you open the tap, the water starts off at full pressure and then reduces until it can only get out as fast as the blockage will let it.

 

[Chris_E_Dub]

Okay, this will no doubt sound like a right old bodge, but I thought it could either be the pipe of tap itself, so I thought I would swap the taps around. Unfortuantely my adjustable wrench wouldn't open wide enough to release the taps from below, so I removed the 'innards' of the two taps (hot and cold) and swapped them over.

Now the hot works fine, so that ruled out the possibility of it being a problem with the pipe. However, the cold tap is now not working properly (or rather the mechanism within it isn't). I believe you can buy replacement inners (sorry for the lack of technical speak) for taps – is this the case? Or am I better off jsut replaceing the entire tap?

 

[oilman]

If you can buy the inners, great. If not how about a tap that has the same inside dimensions and swap the inner over. That way it will save a lot of thankless work trying to change the body.