Hot water problem

[RMG]

We have a Halstead Eden CBX32. The heating works just fine and we have loads of hot water downstairs. The problem is in the bathroom. The water is luke warm at best. Also the pressure gauge fluctuates from 1 bar to zero over a day or so.
Any help would be appreciated, apart from suggesting a new boiler

 

[Bahco]

the pressure gauge fluctuates from 1 bar to zero over a day or so.

You have a leak somewhere on the central heating somewhere which is why you are losing pressure.

 

[RMG]

You have a leak somewhere on the central heating somewhere which is why you are losing pressure.

Wonderful. All the pipes are under the floorboards.

Any thoughts on the lack of hot water in the bathroom?

 

[bengasman]

does it actually fluctuate, or go down and then you top it up?

 

[RMG]

It goes down and I open the valve a little to bring it back up. It can then stay stable for a few days before dropping again.

 

[blondini]

You have a leak somewhere on the central heating somewhere which is why you are losing pressure.

Wonderful. All the pipes are under the floorboards.

Any thoughts on the lack of hot water in the bathroom?

Could just be leaking from the pressure release valve on the boiler. Check outside to see if the vent pipe is dry.

Lack of hot water temperature on some taps could be due to higher flow rate than the boiler can cope with. Try closing the bathroom taps down a bit to see if it warms up.

 

[RMG]

Lack of hot water temperature on some taps could be due to higher flow rate than the boiler can cope with. Try closing the bathroom taps down a bit to see if it warms up.

Thanks, we'll give that a try.

 

[MANDATE]

If your expansion vessel is not functioning correctly cause it may have lost some of its air pressure, there is nowhere for the water to expand into. This will result in the water pressure exceeding the setting on the pressure relief valve. The relief valve will open and water will be forced out through the exit pipe (outside). I believe these valves once opened don't fully seal again.
If you tie a clear plastic bag on the end of the pipe, you'll be able to see if it collects water.

 

[RMG]

Mandate, the expansion vessel was replaced last year by BGas Homecare, and there is no outflow from the pipe. I can see it from where I sit. And besides, wouldn't that affect the whole of the system and not just the bathroom? I'm beginning to think blondini is right, the boiler just isn't man enough for the job, but at 32Kw it ought to be.

 

[blondini]

I'm beginning to think blondini is right, the boiler just isn't man enough for the job, but at 32Kw it ought to be.

Even 32kw won't cut it if the flow is too high. My mains water pressure and flow are pretty good but my combi could only deliver warm water on full bore. The cold water flow through the boiler needed to be restricted to bring the temperature up.

 

[RMG]

So, will it help if I close the stop cock on the mains a couple of turns?

 

[blondini]

No, if you close down the stop cock then drawing cold water would reduce the flow through the boiler too much if you were drawing hot water at the same time. I just put a valve on the cold feed to my combi and tweaked it down to get adequate water temperature with the taps full on.