Pump position

[charlie_parker]

Hi Guys,

Oil boiler (18 yrs old) ground floor

I've just shifted my cylinder out of the loft into the bathroom cupboard (first floor). While I was at it I fitted a mid pos valve etc and now have a Y-plan system. Had difficulty positioning pump as room restricted so run feed from bolier behind cylinder to tee (vertical outlet f & e feed and horiz outlet to second tee). At this tee the top outlet is the vent and bottom outlet to the pump, then 3 way velve etc. Pump is above cylinder.

All works fine but hot water entering f & e tank. The distance between cf and ov is less then 150mm as advised by J.Mac's Pump Tool with the pump a further 100mm away..

Does this mean the static head (about 2m) is insufficient? The pump (standard Wilo) is set at 1 and the system appears to be working fine. I even tried lifting the f & e tank up another foot without success. Vent a good 4 foot above the f & e tank.


Would appreciate suggestions as it's getting cold

Thanks a lot - Charlie

 

[giblets]

Should the first tee not have been the vent & the second tee the feed? I know it's shown the other way round on Pump Tool but in my mind this is not correct.

 

[doitall]

The cold feed should be between the vent and the pump

 

[Guzzles]

Yeah, I think you've got things the wrong way around. If you do a search on google books, for NVQ plumbing you can get a preview of a really useful book. It tell you that you need the vent first, followed by the feed (both within 150mm of each other), and the pump should be ideally facing upwards. It also mentions that to get rid of any bubbles, the pipe before the vent should ideally be horizontal for 200mm. Hope that helps!

 

[Terrywookfit]

Fit a myson aerjec as instructions supplied with it!!

 

[charlie_parker]

I noticed the conflict between J.Mac and other diagrams but chose to go the J.Mac way! Well I've just changed it and after 10minutes I peered into the tank and can still see hot water swirling in from the feed pipe. Doesn't appear much and have reduced the level to see if the water is rising and it appears not. Could it be conduction?

The heating was on for 6 hours last night and the level didn't seemed to rise and nothing from the overflow, though the water was slightly clouded.

Grateful for your replies as it's really frustrating thinking all is as it should be but is apparenly not right.

Charlie

 

[doitall]

Perhaps you should post a pic

 

[bengasman]

Are you sure pump is not upside down?

 

[Terrywookfit]

Are you sure pump is not upside down?

Which way is up ??
Do you mean is flow in correct direction??

 

[charlie_parker]

see picture at

http://picasaweb.google.co.uk/charlieparker45/CharlieParkerSBoilerLayout/photo#5162451480259440914

pump not upsidedown and the stat was installed by previous occupant

Charlie[/url]

 

[bengasman]

You should be able to see an arrow on the side of the body of the pump, if it points up, pump is upside down, nothing to do with the label.

 

[doitall]

So which is the cold feed the left or right pipe

 

[charlie_parker]

cold feed on the left (15mm) and vent on the right (22mm)

and pump definately correct

Charlie

 

[bengasman]

Any chance there is some sort of bypass?
How much water is getting into the tank with pump on 1, and how much on 2 or 3?

 

[giblets]

CP, are you meaning "pumping over" from the open vent or water welling up from the cold feed connection into the tank? If the latter then I should not worry as the cold feed is doing it's job i.e. allowing the expansion of 1/23rd of the system volume on heating up.