Hot water problem - not very hot & taking ages to heat u

[mi-key]

To cut it short, have bought a house that has a Danesmoor 15/19 oil fired boiler installed - is only 18 months old.

For the first few months we had lovely scalding hot water all the time, but unfortunaltey discovered that this was because the immersion was permanantly on, leading to a HUGE electric bill.

So, turned off the immersion, reasoning that the boiler should be good enough to fill a tank of hot water on its own.

But... it is possible to get it hot, but only without the heating on, and it takes a very long time to get enough for a bath ( even then the water isnt that hot ). Also, when the boiler is set to just run the hot water, the radiators also get hot.

I thought it may be something like a problem with the diverting valve ??? but have looked and cant find one anywhere connected to the pipework ( not really sure what I should be looking for anyway ! ).

Also, there is a thermostat on the side of the immersion tank, but following the wiring, this isnt connected to anything.

So - any clues why the boiler cant make just the hot water come on, and fill the hot water tank reasonably quickly ?

The CH works fine, and the radiators are nice and hot - just need to get some of that hot water to come out of the taps !

If it helps, the system does have a seperate metal tank in the loft, the hot water cylinder is in the airing cupboard.

Any help or advice on what to check much appreciated

Mike

 

[gas4you]

Sounds as if the system has not been wired up to allow the hot water to come on on its own! Indeed if this is the case one wonders what else has been omitted

Somewhere you should have a 3 port or 2 x 2 port valves which will be controlled by the room stat and cyl stat. Follow pipes from side of h/w cylinder back to see.

How many pipes have you off the boiler. 2 or 4?

If 4 then it looks like a gravity primary system, if 2 then fully pumped.

If 2 pipes and no valves then I think you need an expert in to have a look to see what mess has been made of this installation

 

[mi-key]

There are 4 pipes coming off the boiler.

There was a room stat on the wall of the hall, but this also wasnt actually wired up to anything.

As far as I can tell the boiler was replaced a year before we moved in, but the rest of the system is all older. It look as though whoever installed the boiler didnt connect up the room stat and cylinder stat to the boiler for some reason ?

I havent seen anything connected to the pipework that looks like either a 2 or 3 port valve, quickly tracking the pipes from the side of the cylinder, they seem to just connect directly to the boiler ( by way of the attic with smaller pipes running off into a metal tank ).

 

[gas4you]

Sounds like a gravity hot water system then. The pump will only pump water around the radiators, not the hot water coil. This should still give you piping hot water though unless there is a blockage or air lock in the grayity pipe work.

I stand to be corrected but but it is my understanding that any boiler change carried out about 18 months ago should have been converted to a fully pumped sytem to comply with Part L energy efficiency regs and the CHeSS code of practice, whether it was oil or gas

 

[mi-key]

Am pretty sure it is a gravity system. Checking the paperwork, the boiler was installed 24/11/04 - but the house was empty for over a year before we moved in, so the boiler has only had around 18 months use - not sure if the installation date would make a difference to the regs ?

On the control panel there is a 5 way rotary control that controls the heat of the rads, would this by why the system doesnt have a seperate room thermostat ?

Is there any easy way to check for air locks or blockages ?

Ta
Mike

 

[Nixt]

Given the installation date the gravity dhw should have been upgraded to at least C-Plan, where gravity is maintained but with a zone valve and cylinder stat interlocked with boiler (now of course all boiler changes must be fully pumped). Your boiler is not faulty however. Check how old the cylinder is as well.

The rotary control does not replace roomstat. It is the boiler control stat and should be left 2/3rd max in summer and almost at max setting for winter. This is because boiler return temperature should be maintained at over 55C.

 

[mi-key]

The cylinder looks pretty old, it doesnt look as though it was changed at the same time as the boiler.

So what are the options ? if it isnt a fault as such with the system, is it going to be case of getting someone in to update the plumbing and fit the valved etc... needed ?

 

[Nixt]

The controls should be brought up to date. If cylinder is old and crusty its worth changing for high recovery type. Plumb center do an own brand one HE85 £146+vat approx including a new immersion (c/w safety cut off).