No hot water. On the verge of tears

loopyloulou_3

I really dont know what to do, there is something wrong with my boiler and i am far too scared (money wise) to call a plumber out. I am getting very little hot water at all, it runs hot for about 30 seconds and then goes freezing cold again.

Not sure what to do now :-(

Browntoa

what make of boiler is it ??

it can be a thing called the diverter valve

http://www.diyfaq.org.uk/plumbing/combi.html

When Hot Water (HW) is demanded, a HW-priority diverter valve is used to direct the output from the boiler away from the CH circuit into the small secondary heat exchanger where it heats the Domestic Hot Water (DHW). The valve is generally not motorized and a variety of mechanisms are used to operate it, e.g. wax pellet expansion, water flow venturi etc. Often the temperature of the primary heat exchanger is also increased when DHW is demanded

these are in the region of £70 to £130 depending on the make , plus labour to fit (half an hour...hour at the most)

tkblueyonder

loopyloulou wrote:

I really dont know what to do, there is something wrong with my boiler and i am far too scared (money wise) to call a plumber out. I am getting very little hot water at all, it runs hot for about 30 seconds and then goes freezing cold again.

Not sure what to do now :-(

call a heating engineer and agree a fixed price for them to come have a look and then give an estimate for work needed ...?

Browntoa

check that the pressure on your boiler is up in the green area on the guage, normally marked 1 - 1.5 bar.... could be low pressure in which case you need to put more water in from the filling loop

http://www.ultimatehandyman.co.uk/TOPPING_UP_A_COMBI_BOILER.htm

Combination boilers or "combi" boilers as they are more commonly known sometimes stop working due to a drop in pressure. In most cases this is easily rectified and will take seconds. Pressure can be lost in a central heating system if for example the radiators are bled, if the combi constantly looses pressure than you have a leak! This could be something as simple as a bleed valve that is not closed properly or a radiator valve that is leaking slightly, check all radiator pipes and valves for evidence of leaking. Leaks are normally very easy to spot as the water in the system is discoloured, if you find a leaking valve try to re-tighten it to stop the leak, otherwise replace the valve!



The picture above shows a regular combi boiler.

The filling loop must not be connected to the boiler permanently as it only used to top up the boiler
if pressure has dropped. In reality these are permanently connected as people very rarely disconnect them.
There are two dials one of which is the pressure dial and the other which is the temperature.
Below the boiler is a filling loop which comprises of a flexible pipe, a handle and a double check valve.
The double check valve prevents water from the central heating being sucked back into the cold water
supply for the house.
The pressure dial should have a red line on it to signify the minimum pressure required for the boiler to work.
This dial will increase in pressure when the combi is heating water so ensure that the central heating part is
off and that no hot water is being drawn. If there is no red line then check the manual for the combi as putting too much pressure in the boiler will cause the blow off valve to blow, which will be vented outside of the property.
Most boilers require just over 1 Bar of pressure when switched off.
If the pressure is below the minimum required for your boiler then slowly open the valve on the filling loop, this normally has a handle attached but a suitable tool may be needed. You should hear the water moving into
the combi! Keep an eye on the pressure dial and when it reaches the correct pressure turn the valve off!
You can now use your boiler as normal.

could be worth turning the system off for a few minutes at the power switch, let the thing totally reset then put it back on and let it fire up

loopyloulou_3

my boiler is vaillant

there is a gauge on the boiler - the top half of which shows the temp of the water in the central heating unit - this is not working at all and is well below zero degrees C.

The bottom half is the pressure which keeps dropping. my OH keeps altering it to about 2 or 2.5 bar - although in our manual it says it should be between 1 and 1.5 bar. I am worried that he is doing more damage by doing this (although it is still below the red line)

ahhhh i dont really understand these things at all - but am worried that i wil call a plumber out - not have a clue what he is talking about and i will get charged a small fortune.

Browntoa

does it actually fire up the boiler when the hot water is turned on ??

love_lifer

look at a manual and call a useful friend. id recommend also stopping fiddling. its likely you know someone with a bit of a clue so call them quick...

loopyloulou_3

it fired up when i turned the water on, but my OH just upped the pressure to 2 bar.

browntoa - your not a plumber by chance?! im from medway too!!

loopyloulou_3

one of my friends is going to come over 2moro and have a look
fingers crossed he can help! i am next to useless!

Snow_Dog

If the pressure keeps dropping then you are losing water somewhere in the heating part of the system.

The pressure meter measures the water pressure in the radiators which in a combi are a sealed system.

If this pressure drops too far then the boiler will simply not work for safety reasons.

If as you say you need to keep repressurising the system then you have a leak somewhere, that is the first thing you need to find. Look round for damp patches on the carpets by each end of the rads is most common.

If you have a leaky rad valve then that is easily solved and will stop the pressure dropping.

A heating eng. should not charge much for a rad valve and worst case if the rad needs changing then £300 absolute max. and thats pushing it. (provided you have found the leak for him)

Oompa_Loompa_2

loopyloulou wrote:

I really dont know what to do, there is something wrong with my boiler and i am far too scared (money wise) to call a plumber out. I am getting very little hot water at all, it runs hot for about 30 seconds and then goes freezing cold again.

Not sure what to do now :-(

Hi, have just noticed this post. I had this problem for 3 months when I moved into my new flat! I put up with it for that length of time because my estate agents usually don't get anything done, but coming up to winter I couldn't deal with it any longer. So... it turned out to be a small circular black rubber thing in the boiler (anyone know the correct name for it?) which presses against something else to give you hot water. This small rubber thing had holes in it, therefore wasn't pressing againt the switch for hot water. The plumber replaced it with a new one and ever since then I have had boiling hot water.

This may be the problem with your boiler - but if anyone with any expertise had an estimated cost or proper names that would be great. Sorry I couldn't give you this info.