No heating - poor chilly me!

[Mrs Spanner]

Hi everyone!

We have a delightful old worcester danesmore oil boiler which yesterday stopped producing heating The boiler is firing up and the pipes/exhaust are getting hot but the radiators are stone cold...It was working fine yesterday morning so no warnings, it just suddenly stopped. The thermostat seems to be clicking over ok.

Would a faulty pump be the chief suspect? Are there any other things it might be? Pump is a grundfos 15-50.

Does the pump also drive the hot water circuit - i.e. before we get it fixed, can I still have the hot water set and running? The hot water tank is directly above the boiler.

Thanks in advance!

 

[cozzmic]

Sounds like you have a gravity hot water heating and pumped CH. Are there two large pipes from the boiler to the HWC and two to the CH thats an old system design. Probably the pump faulty or a room stat turned down too far.

 

[Mrs Spanner]

Thanks - it looks as if there are 4 pipes from the boiler (it's a 1983 model), and I counted 9 of varying sizes in the airing cupboard so it was a bit difficult to tell what's going where...

Thermostat is definitely up high enough, when it first happened I cranked it right up to the top and it clicked in as normal but still no heat

 

[WDIK]

prime suspect pump, feel it or stick a long screwdriver on it and the handle to your ear, can you hear it?
if not SWITCH IT OFF undo the large silver screw in the centre of the pump, insert small screwdriver and engage the pump shaft, it may just be seized if your lucky and you may free it up, if it was seized and you do free it then switch back on it may be ok.
if the above doesnt work and you cant hear it, get it checked either the power or the pump have gone.

 

[bengasman]

9 pipes? NINE??? That probably means you have a variety of tanks and all open vent. This probably means that in 25 years the system has gathered an impressive amount of corrosion, dirt and limescale.
Thorough clean out would be advisable, possibly just chemical, but more likely a powerflush will be needed to get 5kg of limescale out

 

[Mrs Spanner]

Not sure if any of them are pipes heading off to radiators or taps though, it's a bit of a jungle in there, and they're all round the back of the tank so I can't really see where they are all heading! There are two tanks in the loft from memory...

I'm sure you are right about a jolly good clean out though, we've only been here a few months and there is a pile of regular boiler servicing receipts but nothing more substantial than that!

We took out the immersion in our previous house and ewwww...the colour and consistency of the water coming out of the bottom of that made me feel sick, it was just like the blue lagoon.

 

[bengasman]

We took out the immersion in our previous house and ewwww...the colour and consistency of the water coming out of the bottom of that made me feel sick, it was just like the blue lagoon.

One of the reasons I do not like cylinders and open vents. The water coming out of the tank that you use to brush your teeth and wash your face is not much better, yuck!

 

[Mrs Spanner]

prime suspect pump, feel it or stick a long screwdriver on it and the handle to your ear, can you hear it?
if not SWITCH IT OFF undo the large silver screw in the centre of the pump, insert small screwdriver and engage the pump shaft, it may just be seized if your lucky and you may free it up, if it was seized and you do free it then switch back on it may be ok.
if the above doesnt work and you cant hear it, get it checked either the power or the pump have gone.

Thanks - do we need to turn the water off either side of the pump or can we just undo the big screw straight away - there is some water dripping out of it when we turn it a bit.

 

[WDIK]

its normally used to vent air from the pump, some will come out but its a dribble

 

[Mrs Spanner]

Right - well the pump does seem to be vibrating but we shut it and took the screwy thing out anyway and the inside bit can easily be turned by a screwdriver.

As it's practically Sunday night anyway now we might as well wait and call someone tomorrow now Just to add insult to injury we thought we'd start up the calor gas fire to get a bit of heat and discovered that the bottle is empty there too

 

[giblets]

Have you checked the small feed tank in the roof to make sure it has water in it?

 

[Mrs Spanner]

Thanks for the suggestion - I've just been up into the loft and there are a couple of inches of water in it - the pipe at the bottom of the tank is completely covered; the other pipe and overflow are above the water line.

 

[Bobbo 85.]

mzv in them is there,a 2 port,?

 

[Mrs Spanner]

Thanks for your help everyone - twas a poorly pump - new one installed and Mrs Spanner is now nice and toasty warm again