Hi All,
the three way valve in my central heating/hot water system has failed so I'm now planning on replacing the entire valve and motor unit.
This is probably the 4th time I've changed it in the 20 years I've lived in the house. The current Siemens 3PMP-V22 has lasted over 7 years but I've forgotten how I fitted it, hence I need some advice here.
There is already an Adey Mangefine filter fitted and to help clean the system for the new 3 way valve, I added 500ml of Adey MC3+ Rapide yesterday. I flipped the 3 way valve manual lever to ensure I have some heating and HW for now whist the cleaner circulates.
The 3 way valve, Magnefine filter, HW tank & pump are all located upstairs in the airing cupboard.
The next step is to drain the radiators, my plan is to turn off the isolation valve on the heating header tank feed in the loft, then connect a hosepipe to the downstairs radiator stopcock and open it. This should empty the rads of water and cleaner.
Once empty I should be able to unbolt the 3 way valve, noting its wiring and simply bolt in the new one and rewire. The new valve is a Drayton MAI/678-3, I note that if this goes wrong the motor can be removed and replaced separately from the valve.
My main worry is whether I need to drain the hot water from the tank? For some reason I have it in my head that I did this once before and it caused all kinds of problems, perhaps it was another project & logically I cant see why I would need to drain the HW.
One the rads are refilled I will use inhibitor to help prevent rust etc.
Does this sound right?
All info welcome.
the three way valve in my central heating/hot water system has failed so I'm now planning on replacing the entire valve and motor unit.
This is probably the 4th time I've changed it in the 20 years I've lived in the house. The current Siemens 3PMP-V22 has lasted over 7 years but I've forgotten how I fitted it, hence I need some advice here.
There is already an Adey Mangefine filter fitted and to help clean the system for the new 3 way valve, I added 500ml of Adey MC3+ Rapide yesterday. I flipped the 3 way valve manual lever to ensure I have some heating and HW for now whist the cleaner circulates.
The 3 way valve, Magnefine filter, HW tank & pump are all located upstairs in the airing cupboard.
The next step is to drain the radiators, my plan is to turn off the isolation valve on the heating header tank feed in the loft, then connect a hosepipe to the downstairs radiator stopcock and open it. This should empty the rads of water and cleaner.
Once empty I should be able to unbolt the 3 way valve, noting its wiring and simply bolt in the new one and rewire. The new valve is a Drayton MAI/678-3, I note that if this goes wrong the motor can be removed and replaced separately from the valve.
My main worry is whether I need to drain the hot water from the tank? For some reason I have it in my head that I did this once before and it caused all kinds of problems, perhaps it was another project & logically I cant see why I would need to drain the HW.
One the rads are refilled I will use inhibitor to help prevent rust etc.
Does this sound right?
All info welcome.