The " Finger Test " for circulating pumps

[gas4you]

The thing is a DIYer is going to work on gas regardless of what any of us say on here

As long as we point out the error of their ways, point them in the right direction, what else can we do

 

[Agile]

Tony - add it to the FAQs??

At first sight that seems like a good idea!

However, a DIYer search on the plumbing forum does not bring up results inside the FAQ as fdar as I can see.

Secondly I dont have editing rights which are sometimes needed and which I would dearly like to use on the FAQ about pressurising expansion vessels!

So I posted this within the heating forum so that i could refer to the finger test and readers could easily look it up without having to ask where the "FAQ" were!

Tony

 

[scatmanjohn]

so that it does not give the public the impression that RGIs dont know what they are doing.

Why hide the truth, lots of them don't.

 

[Agile]

I did a repair for an Israeli guy last week and he had been told that the system needed a power flush at £350.

He was suspicious and asked round and got my number and I came round and replaced the CH sensor to fix it for under £100..

Tony

 

[scatmanjohn]

I did a repair for an Israeli guy last week and he had been told that the system needed a power flush at £350.

He was suspicious and asked round and got my number and I came round and replaced the CH sensor to fix it for under £100..

Tony

Just the point i was making.

 

[kevplumb]

I have found it much easier and a lot less b****y if you remove the vent cap/screw from the front of the pump, and gently putting a screwdriver into the hole, testing the resistance of the impeller against the screwdriver, i.e. can you stop the impellor easily when running.
You can also try and spin the impeller with a screwdriver when in situe to see how free it is. Using a finger seems a bit crude, how about a carrot instead?????????

one good way to knacker a screwdriver and the slot in the pump shaft

 

[Agile]

The Grunfos pump has a smoothed off screwdriver "slot" and you cannot grip the impeller enough to easily measure the starting torque or to free up a jamed rotor.

They say this is for safety reasons!

Its odd though that Wilo dont see any danger and have a nice strong slot which will enable most jammed rotors to be freed up.

Tony

 

[screech]

now this test can be useful for some people but i can think of a few problems

pump valves - ball type valves are useless and the manufacturers guarantee probably states that if they are used to isolate the pump they will then leak 95% of the time and will require new valves. gate valves may leak but they can be repaired but then again they don't always shut off so you'll need a bowl and some towels or tissue to direct the water.

when replacing the pump head due to the seal being disturbed there's also a good chance it may leak, especially if it's an older one.

one big thing to remember is if there's any muck in the pump impellar it needs to be cleaned or covered over otherwise the walls will be covered with dirt.

 

[powermaxer]

agile,tony keep wearing your finger away like that and you are out of the darts team.

 

[Agile]

I was the manager of the darts team as I was not a terribly wonderful player.

The others remembered when I finished from 98 but thats about the easiest thing to do as even if you get it wrong it still leaves you with an alternative way out in most cases.

Tony

 

[powermaxer]

after darts its the chinese resturant,with your worn away finger how you use chop sticks.