Boiler/Heating help please

Canucklehead

Hi

Look at the pump.
Right hand side is the speed control
Behind that is the body of the pump, stamped into the casting is an arrow, not very easy to see but it's there.

Which way does it point? http://www.screwfix.com/app/sfd/cat/lrgimg_popup.jsp;jsessionid=FQ2U1ONDQNAR0CSTHZOCFGA?productId=50183&imageNo=null&ts=34758

GSR.

sancho

The arrow is pointing down

The plumber just rang and said he can come Friday morning. He said a new pump would be 60 quid (the one you linked to was £74) plus 25 for an hours labour. If the valves around it aren't working it would mean replacing the valves and obviously the extra time/labour. That a reasonable price? Am in lincolnshire

keystone

sancho wrote: »

Am I right in thinking that the two pipes going up out of the picture come out of the tank in the loft, the one on the left being the open vent(?) which the water is coming out of, and the one on the right being the cold feed in?

This is what I think you have in terms of pipe function:



I do suspect a magnetite buildup and I'm willing to bet that the airsep is also blocked to a certain extent.

Both of those pipes are ridiculously hot. Have ran a magnet over all around that area but it doesn't stick, and feels consistently ridiculously hot if that makes sense

Yes it does to me. Hot water is rising up from the boiler - more so since you've turned up the stat and you may have reahed the stage when you have blown some of the gunk out allowing the system to pump over via the airsep and the vent to the F&E tank. The feed will also be hot because the hot water is rising up that way to the F&E too as it has nowhere else to go.

I agree with CH - time to take the pump out and have a look see and certainly don't do it yourself. Those pump valves will most likely be solid as a rock.

Bet the pipework north of the upper pump valve has severely restricted bore.

I'm not, at present, convinced it needs a new pump.

Cheers

Canucklehead

sancho wrote: »

The arrow is pointing down

The plumber just rang and said he can come Friday morning. He said a new pump would be 60 quid plus 25 for an hours labour. If the valves around it aren't working it would mean replacing the valves and obviously the extra time/labour. That a reasonable price? Am in lincolnshire

Yes, good price....would recommend (and always fit) Grundfos.

Ho hum, arrow is pointing the right way.

There's a slim chance a check valve has been left in the system from way back and has blocked up. It could be inaccessible by now. Just a thought .

If you don't come back and report the results ............

GSR

keystone

sancho wrote: »

How long would you expect the boiler to come on for at a time? It's never on for more than a few minutes. I can't remember hearing it in my old house, it's only that it's in the front room it's noticeable I suppose.

If you've got the blockage I think you have then it won't because the flow will just get redhot awith the water going nowhere until the boilerstat shuts it down.

Thinking about it perhaps the lady we bought it off said that her husband fitted a new pump before we moved in, but I could be wrong (her husband was definitely not a plumber)

He should have checked that pipework north of the upper pump valve when he did it but its easy to be wise after the event.

Cheers

sancho

keystone wrote: »

I do suspect a magnetite buildup and I'm willing to bet that the airsep is also blocked to a certain extent.

Yes it does to me. Hot water is rising up from the boiler - more so since you've turned up the stat and you may have reahed the stage when you have blown some of the gunk out allowing the system to pump over via the airsep and the vent to the F&E tank. The feed will also be hot because the hot water is rising up that way to the F&E too as it has nowhere else to go.

I agree with CH - time to take the pump out and have a look see and certainly don't do it yourself. Those pump valves will most likely be solid as a rock.

Bet the pipework north of the upper pump valve has severely restricted bore.

I'm not, at present, convinced it needs a new pump.

Cheers

Thanks (especially for the labelled pic ), so if that pipework needs replacing I'm guessing it will bump the cost up a fair bit. How will they tell if the pump does need replacing, would be concerned that he will just say it needs changing when it might not necessarily need it.

Thanks again CH

sancho

keystone wrote: »

If you've got the blockage I think you have then it won't because the flow will just get redhot awith the water going nowhere until the boilerstat shuts it down.


Cheers

Would you expect it to heat the house though? It's pretty much just come up to a temperature that's reasonable (after being on since 1 o'clock)

keystone

sancho wrote: »

Thanks (especially for the labelled pic - off to see what a 'mains riser' is)

Its the mains cold feed up to the roofspace.

so if that pipework needs replacing I'm guessing it will bump the cost up a fair bit.

It should not cost an arm and a leg - its just a few lengths of pipe and a tee and TBH I'd be dumping the airsep and just teeing off for the vent anyway these days. It'll need a bit of a drain down to do but its no more than 45 minutes work or thereabouts.

would be concerned that he will just say it needs changing when it might not necessarily need it.

Thats the 64k dollar question. I'd want to check pipework FIRST and sort if required and then think about the circulator. As CH observed and you've confirmed its newish anyway but if its been running without water to provide its lubrication it may well be a tad on the knackered side - can't tell from here.

Cheers

sancho

keystone wrote: »

Its the mains cold feed up to the roofspace.

Damn, you got there before I edited it!! I had a think about it and worked out what it meant

keystone wrote: »

It should not cost an arm and a leg - its just a few lengths of pipe and a tee and TBH I'd be dumping the airsep and just teeing off for the vent anyway these days. It'll need a bit of a drain down to do but its no more than 45 minutes work or thereabouts.

Thats the 64k dollar question. I'd want to check pipework FIRST and sort if required and then think about the circulator. As CH observed and you've confirmed its newish anyway but if its been running without water to provide its lubrication it may well be a tad on the knackered side - can't tell from here.

Cheers

Presume there will be an easy way of them telling if it's blocked then. Probably more technical than my commemorative Floridian fridge magnet though.......

keystone

sancho wrote: »

Would you expect it to heat the house though? It's pretty much just come up to a temperature that's reasonable (after being on since 1 o'clock)

It will if you've cranked the boilerstat up such that sheer dynamic forces have blown some of the crud out and achived some circulation. It also will if you've been getting some reverse flow. As suggested earlier it might not be a total blockage - a partial one is enough to screw everything up (Ooops nearly wrote something else there ).

I had one like this a while ago on the heels of a certain (nameless of course) plc where the house was getting warmish on the top floor and merely tepid downstairs but there was some limited circulation. I found that the airsep was totally clagged up and the bore of the pipe just after the cold feed joins was reduced to no more than a pinhole.

2 powerflushes and a new pump with an enormous bill from said plc hadn't fixed it and they decided that the only soloution was a new boiler! Sorting that pipework out on the Friday evening fix it. I got called back again on the Saturday morning because the householder was then too hot! LoL.

Cheers