Tests that prove a pump is working ??

[anto_mac_1001]

Hi - I have a WILO 50 pump which 'appears' to be working hard but the radiators downstairs are not heating at all. Upstairs rads get hand hot even with the TRVs fully opened and the controller CH temp set to MAX. They also heat up 3 times a night via the controllers settings.

I bled the pump and I was able to turn the impeller easily using a screwdriver when the pumps off and when it's on the same screwdriver inserted chatters against the what feels like a cog wheel (impeller?).
I drained a litre of water (very slightly brown tinged) from the only radiator drain cock in the system - downstairs.

Also the whole CH system roars successively louder as the speed of the pump is increased. HW comes on with no problems.

So do I have a working pump or not - anyone?

 

[Mike Jackson]

It's difficult to tell. The symptoms your describing could be down to a faulty impeller on the pump but equally the system could be sludged up. If the system water is dirty it sounds like it would benefit from a flush.

I would be looking at powerflushing the system and replacing the pump with a grundfos.

Mike

 

[anto_mac_1001]

Thank you Mike. Unfortunately a further development occurred last night - no rads came on at all even though the boiler fired up and the pipes leading to and from the pump, and to the CH motorised vavle were very hot indeed. Would a sludge blockage cause this?

 

[sonray ltd]

sounds like the pump didn't run. how long was the boiler running ?
was it cycling on/off or running for long periods ?

 

[Mike Jackson]

I'd agree with that, sounds like the heat from the boiler has risen to the pump and valves by gravity.

Mike

 

[anto_mac_1001]

Sonray/Mike - the boiler was running for about 12 hours solid. Today, after leaving everything off for 12 hours there was a semi-return to the previous limited state (2 rads heating on and off as directed by the stat/controller). I turned the boiler temp setting about a third down from MAX and lowered the stat/controller temp for CH down to 20oC and two radiators heated up.

I noted that the CH actuator lever was not going all the way when it went to 'vent' - nor does it go back all the way when it goes to 'fill'. Could it indicate a sticking ball valve or dodgy actuator? I moved the lever manually the full way across but I m not sure if that helped any.

I was considering prizing off the CH actuator (Honeywell smartfit) and swapping it with the HW one because we don't use hot water that much with an electric geyser for dishes and an electric shower. What do you think? BTW guys thanks for enduring the way I am trying to explain myself.

 

[sonray ltd]

prizing it off.

is it the honeywell smartfit that is black with the white lever ?

 

[anto_mac_1001]

Sorry to take so long to reply sonray. Yes It is a smartfit and black yes, I can't see a lever though. I was able to download a Honeywell guide to installing the smartfit system and it shows how to remove an actuator. I tried to put a screen print of the actual page from that pdf document in this post but it didn't work

I did add two images to an album on my profile on this site perhaps you would be so kind as to look at it for me and tell me what you think? The guide says that installing one of the actuators is just a 'snap-on' affair as long as the "...actuator blade and valve stem slot are properly aligned..."

Am I right then in thinking that the actuator head is a modular item that sits on an interface on the valve and that there should be no water when I swap them over do you think.

 

[sonray ltd]

yes i know the smartfits well
the white lever is on the top cover points where the valve is.

1, yes they just clip off no water. with a screwdriver.
2, they very rarely fail when the do they give a signal on the programmer
f4 if i remember.
you could try it and change the cable on the main unit to.

also every fault with the smartfit has a code.

i've only read your post quick earlyer.
so what is happening is you say you put heating on at programmer, wall stat calling, valve opens, pump boiler run.

but your only getting upstairs rads hot not downstairs. is that it ?

 

[anto_mac_1001]

Thanks sonray. Oh that lever (right in front of me) yes there is a white lever, sorry.

Sonray - You have been a great help and so patient I do appreciate it.

You said " i've only read your post quick earlyer.
so what is happening is you say you put heating on at programmer, wall stat calling, valve opens, pump boiler run.

but your only getting upstairs rads hot not downstairs. is that it ? "

Yes thats it in a nutshell. That and the apparently restricted movement of the CH actuator lever (which I intend to short term fix by swapping the unit with the rarely used HW actuator and cable too)

 

[sonray ltd]

i've never really seen that happen on these.
useally when these fail they never move at all or they move from side to side and don't stop giving a f4 fault code.

plus you can't operate these with the actuator off as they rely the resistance of the valve to hold them open or closed.
if you take it off and operate it it just gos side to side.


as for your one try removing the actuator and moving the brass spindle with a pair of pliers. see if its free ( i would say it is)
also try changing the two actuators over they are the same.

the valve could be abit sludged up.


but going by what you have said the whole system is sludged up.
whats the condition of the f/e tank in loft ?
when the boilers on the pipework is hot around pump, mot valve is it hot past mot valve ?


HAVE A MUCK ABOUT WITH THAT FOR TONIGHT.

if the pipework is just as hot past the pump, mot valve etc i think the problem could be with a sludgy system.

how many rads unstairs ? how many are getting hot/warm
upstairs ?

how many downstairs ?
how many dropdowns do you have from upstairs to downstairs rads

(that the flow/return pipes to feed downstairs rads in pairs)

 

[anto_mac_1001]

Theres no fault code being presented at all Sonray. I have swapped the two actuators and when they are swapped the one that was behaving correctly (HW) behaves poorly.

The spindles are free.

I emptied out the F & E tanks - it was thinly lined with orange gunk. I refilled it when it was spotless. I do suspect a dirty system as I've removed and flushed out three rads and the water was black, but not sludgey.

Now I don't think the pump is working though. Theres no hot water or heating. A screwdriver will clatter when press against the rotor of the pump with the large centre screw off, but what does that prove eh? Could that just be hot water rising (convection) from the boiler and whizzing past the impeller? The boiler works fine.

The pump has sat working upside down for 7 years now.

If I take off the head and turn off the valves to it (which are both passing BTW) can I get the controller to call it with 'CH ONLY' and watch it operate?

Sonray et al. Just a recap up to date. There is no heating or hot water. Last night I removed the pump head and cleaned it - I also plugged it into a plug into the mains and at each speed the pump worked fine (covering me and my bedroom in fine black water ...)

To remove the pump head I had to isolate it via two ball gate valves. The valve nearest the boiler was opening and closing and water gushed into the pump body which was still in situ in the pipework. But when I tried to close the valve just after the pump it was very stiff. I WD40'd it and tried to close it - it closed. Then I tried to open it but it wouldn't budge the 'pchunnngg' and now the spindle spins free as a bird either way but the valve ball is firmly shut.

Is the valve kaput now? Is this an easy repair? Should I drain down? Do I need any special tools or compounds (eg PTFE tape, etc)?

Any help warmly greeted

 

[CharterGAS]

try blocked cold feed!!!
and to test a pump use a multimeter on ohms and measure across L+N with the power off and you are looking for 150 - 300 ohms outside of that the pump needs replacing.
When you jamm a screwdriver in the impeller you are looking to see how hard it is to stop. It should not stop easily, if it does replace the pump.

Why would grundfos be any better than Wilo??

 

[Mike Jackson]

Those ballofix pump valve are the work of the devil. You'll need to drain down to change them. Change the pair as the other is likely to fail as well. Get pump gate valves to replace them with.

Mike

 

[anto_mac_1001]

Thanks Charter and Mike. I only bought the one valve (gate - thanks Mike) for replacement but I am going to do a good overhaul of the system after Xmas - I have bought Fernox F3 and I will introduce Sentinel X100 after Fernox has done its work. During the drain to do Fernoxing (I don't believe I made a verb outta that) will replace the other ballofix valve for a gate. I have learned the hard way that central heating is not to be taken for granted. After a full service I will get me some insurance too.

Thanks for everything guys

Merry Xmas
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Have a nice 'just another day'
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