What have I done to my Megaflow?

[DaveColchester]

Hello all!

My Megaflow worked fine before - water pressure was good upstairs and downstairs.

In order to disconnect a broken washing machine I turned off the water at the mains and drained all the hot and cold water from the system (I realise now that this wasn't actually necessary).

After turning the mains supply back on I noticed the water pressure was much lower than before especially upstairs. I looked around on the internet and came to the conclusion that maybe I needed to regenerate the air gap - I followed the instructions on the boiler to do this but it didn't improve the water pressure.

What have I done?

Thanks

 

[Agile]

If a WMC has been properly connected it will have isolating valves at the supply end of the hoses. Thats all that needs to be turned off.

I cannot guess what problem you have initiated but work on an unvented cylinder should only be carried out by a qualified person for safety reasons.

Tony

 

[muggles]

Are you sure you've turned your stopcock back on fully? Is it just the hot that's affected or both the hot and cold? Is one worse than the other? Was your stopcock particularly difficult to turn on/off?

 

[kevplumb]

If a WMC has been properly connected it will have isolating valves at the supply end of the hoses. Thats all that needs to be turned off.

I cannot guess what problem you have initiated but work on an unvented cylinder should only be carried out by a qualified person for safety reasons.

Tony

another usefull post

I cannot guess what problem you have initiated

so why bother answering the post then

personally i would be looking for and checking filters on the flow in

 

[DaveColchester]

Are you sure you've turned your stopcock back on fully? Is it just the hot that's affected or both the hot and cold? Is one worse than the other? Was your stopcock particularly difficult to turn on/off?

The stopcock is what I think is called a "quarter turn valve". I'm pretty sure that it is fully open - it wasn't particularly difficult to turn.

Both hot and cold are effected. The pressure from the hot tap is perhaps very slightly higher than the cold tap but still less than before.

 

[gasafengineer]

Are you sure the 1/4 turn valve is open fully? , sometimes these can shear/strip rendering the valve only partially open.

 

[DaveColchester]

personally i would be looking for and checking filters on the flow in

I found this in the maintenance section of the instruction manual:

http://www.heatraesadia.com/docs/Megaflo_systemfit_-_Issue_5_-_36005882.pdf section 8.3

CLEAN THE STRAINER
The strainer is incorporated within the Pressure Reducing Valve housing of the Cold Water
Combination Valve (see Figure 1). To inspect and clean the strainer:
i) Turn off the isolating valve on the Cold Water Combination Valve by turning the black handle so it lies 90 degrees to the direction of flow.
ii) Open the lowest hot tap in the system to relieve the system pressure.
iii) Using a spanner unscrew the pressure reducing cartridge and remove the moulded housing. The strainer will be removed with the cartridge.
iv) Wash any particulate matter from the strainer under clean running water.
v) Replace the strainer and screw the Pressure Reducing Valve cartridge into the moulded housing.
vi) Close hot tap, turn on isolating valve by turning handle so it lies parallel to the direction of flow. Check for leaks.

So I should check this out?

 

[steve32]

what is the cold pressure like at the kitchen sink tap.

 

[DaveColchester]

Are you sure the 1/4 turn valve is open fully? , sometimes these can shear/strip rendering the valve only partially open.

I will double check it when I get home

 

[DaveColchester]

what is the cold pressure like at the kitchen sink tap.

Much better than the cold water pressure in the bathroom upstairs but not quite as good as it was previously. Overall I'd say the downstairs pressure is at an acceptable level even if it is a little weaker than before; it's the pressure upstairs that is my cause for concern. Upstairs the pressure is really poor when it used to be perfectly fine.

 

[plantroom]

. When the black handle is in line with the pipe the water seems to flow but when turned 90 degrees so it is perpendicular the flow stops.

Correct , as you can see it only takes the valve to be partially open & flow rate will be affected , not too common sometimes to have to use a pair of pump pliers to shut these valves off.

 

[holty]

blocked filter comes to mind.

 

[DaveColchester]

I've rechecked the cold water isolation valve.

Untitled

• DaveColchester
• 26 May 2011
• 1

As a few of you suspected it doesn't look quite fully open. I can't turn it any more by hand though - I'll try to get hold of a pair of these "pump pliers".

Once I get it fully open should I regenerate the air gap again?

 

[yourmoneyoryourwife]

looks fully open to me check filters as Kevplumb says the airgap wont be affected by draining down unless your'e nrv is shot then that will regenerate the airgap anyway

 

[picasso]

did you turn off anything else ? the water for your kitchen sink shouldent be coming through the valve you have posted a picture of.