Greenstar Junior 24i taking long time to heat up hot water

[adp1]

Hi there,

I hope someone can help with our problem.

We recently moved into a new property, which is a smallish 3 bedroom house. We are renting.

The boiler installed in this house is a Greenstar Junior 24i.

We have noticed since we moved in here last month that the boiler is taking a long time to heat up the water when we turn on the tap. What typically happens is: I turn on the tap in the kitchen (the boiler is in the loft), and the water initially comes out cold, and 5 seconds or so afterwards it starts to get warm/hot, which continues for the next 10-15 seconds or so.. then the water gets freezing cold for the next 10-15 seconds or so, after which time, the water starts to become warm, and then within the next 20 or so seconds, the water is boiling hot, and it stays this way. It usually takes about a minute or longer to get boiling hot water.

Is this normal?

The same pattern occurs upstairs in the bathroom (which is nearest the loft), although it doesn't take quite as long as the kitchen to heat up the water. Usually by about a 45-50 seconds the water will be boiling hot.

If I try the bathroom tap shortly after I have used the kitchen tap for hot water, then the bathroom tap will heat up quickly. (I"m guessing this it because the boiler has just heated up the water because I used the kitchen tap?)

Anyone have any idea? we contacted out letting agency about this last week, but at this point I didn't realise just how long the kitchen was taking to get hot water, and thought there was just a bit of a delay in the bathroom, where I had to wait for the water to get hot. I was told this was normal with this type of boiler, and that the boiler has to get rid of it's water first, which is why the water comes out cold/warm for a while, and then heats the water up again from scratch. This sounds a bit far fetched to me.

We have a boiler guy coming over one day soon to try to resolve a different problem as well with our central heating.. there is no timer set on the boiler (as far as I'm aware, as the last engineer to visit the property advised that it was turned off), so the heating should all be controller by our thermostat on the wall.

For some reason, at certain times of the day, even if we put the thermostat on 32 degrees, the boiler doesn't turn the central heating on. We can hear the thermostat clicking to show that we are increasing the temperature etc. All throughout this time, the water is still being heated when we turn on the tap.

The boiler has a blue light on the front, and the ECO function is not turned on.

According to the manual for this boiler, it should be able to 'pre-heat' the water when the ECO light is not lit, so why is it taking sooo long to get hot water out of the taps?

thanks for your help,

andy

 

[Corgigrouch]

Don't forget the length of pipe that runs from the boiler to the kitchen tap is filled with cold water and once the initial slug of preheated water has left the boiler then the boiler will take a short time to catch up..... On the face of it it sounds pretty normal to me..

 

[adp1]

thanks for the reply, but to have to run cold water for over a minute in the kitchen before we have any usable hot water seems a bit long.. and we'll end up wasting loads of water also.

in the manual is says that it should be pre-heating the water so we can get hot water fast rather than waiting.

 

[Agile]

Are you QUITE sure there is no timeclock on the boiler only set for certain times to give you heating ?

Tony

 

[mcmoby69]

short answer, google 'plumbing deadlegs'

central heating fault, sounds like you are missing a timer somewhere. or the summer winter switch is in summer mode. cant tell without being there.
your chappie should sort it easy enough.

 

[Corgigrouch]

thanks for the reply, but to have to run cold water for over a minute in the kitchen before we have any usable hot water seems a bit long.. and we'll end up wasting loads of water also.

in the manual is says that it should be pre-heating the water so we can get hot water fast rather than waiting.

But you still have to run off the cold water in the pipe before you can get to the hot water in the boiler.... The joys of having a boiler in the loft.

 

[adp1]

thanks for the reply, but to have to run cold water for over a minute in the kitchen before we have any usable hot water seems a bit long.. and we'll end up wasting loads of water also.

in the manual is says that it should be pre-heating the water so we can get hot water fast rather than waiting.

But you still have to run off the cold water in the pipe before you can get to the hot water in the boiler.... The joys of having a boiler in the loft.

thanks. ok, I understand now. that probably explains in part the reason for the delay in the kitchen. unfortunately, the kitchen is fairly small, and there obviously wasn't enough space there to install the boiler, which is probably why it ended up in the loft.

the bathroom upstairs though is very close to the loft (about 3 meters from the boiler), and even in the bathroom, it can still take nearly a minute to get hot water. could this be due to 'deadleg' piping? I can't imagine there being much excess piping between such a short distance.

 

[adp1]

ok, so I finally managed to get up to see the boiler in the loft.

I was surprised to find that although the last engineer had advised me that the timer was 'off', that in fact, it wasn't off at all.. and this was the reason for the central heating not coming on at certain times.

regarding the problem with the hot water taking ages to reach the taps... because the upstairs bathroom is only a couple of metres away from the boiler in the loft, should the tap in this bathroom be taking over a minute to produce boiling hot water? there can't be more than a few metres of piping involved.

am still considering raising this as an issue with the letting agency. is really annoying having to wait over a minute each time I need hot water. can't imagine what this would be like in the winter when you really appreciate hot water.

 

[Agile]

ok, so I finally managed to get up to see the boiler in the loft.

I was surprised to find that although the last engineer had advised me that the timer was 'off', that in fact, it wasn't off at all.. and this was the reason for the central heating not coming on at certain times.

It surprised you but its what I suggested last Tuesday!

If you insulate the hot pipe out of the boiler that will slightly improve the hot water wait time.

Tony

 

[adp1]

ok, so I finally managed to get up to see the boiler in the loft.

I was surprised to find that although the last engineer had advised me that the timer was 'off', that in fact, it wasn't off at all.. and this was the reason for the central heating not coming on at certain times.

It surprised you but its what I suggested last Tuesday!

If you insulate the hot pipe out of the boiler that will slightly improve the hot water wait time.

Tony

Hi Tony,

Yeh, after reading your post, I decided to try and gain access to the boiler in the loft to make sure of the timer. Your post was a reason I thought to post an update about it. Sorry, I should have quoted your post in my reply.

Do you think insulating the hot pipe would make much of a difference? so do you think that a minute is fairly normal then for a tap so close to the boiler? I didn't realise water could cool down so quickly in just a couple of meters of pipe. and you definitely wouldn't think the boiler is at fault in any way?

 

[McCombi]

The water part of your question sounds normal to me too. My mums house is the same with her kitchen tap due to the distance of piping from boiler to tap. You can check by getting someone to turn on the tap while you're in the loft. If the boiler kicks in when the tap is opened and you can feel the pipe from the boiler getting hot. This would rule out the boiler having a fault.