Can't find DRAIN TAP

[Forlopp]

Hi!

I have gravity-based open system with Baxi boiler and Myson pump (about 7 years old). System supports 8 radiators.

I need to drain down and Fernox system to clear sludge and hydrogen build up. However, I can't locate the drain tap. There isn't one on any of the downstairs radiators which is where I would usually expect to find it. There is a spring loaded knob just above boiler which releases water into overflow pipe but I believe this will only clear water out of the radiators upstairs.

Any ideas? Could I drain the entire system any other way?

Many thanks for your time.

 

[breezer]

I can't locate the drain tap

its in the cupboard under the sink

if its not there look hader, try under the floor

or add one or one of

these

 

[Softus]

Have you looked outside the house, just underneath the level of the internal floor?

 

[Slugbabydotcom]

If you cant find it then take off a rad downstairs - either the smallest or one where least damage will be caused if you happen to spill any of the radiator contents. - Then drain the system from a rad valve.
Some rad valves have a 3/4" BSP thread that a standard hosepipe connection will fit on and others have a 1/2"BSP connection for which I usually make something up from a compression nut and ring and a short piece of 15mm copper to connect to a hosepipe

 

[Forlopp]

Thanks guys,

Checked outside and removed panels at back of cupboard to no avail....so it's either under the floor boards or non-existant. Going to pull up floor boards next.

Really appreciate your help! Happy New Year.

 

[Slugbabydotcom]

It's going to be easier to take a rad off than rip up boards all over the place for something that may not even be there
If you do find the DOV its possible that the washer has stuck so after taking an age to drain the system off you will need a new one anyway.

Whatever it's your decision. Have fun!

 

[Forlopp]

Thanks Slugbabydotcom,

Was just a bit nervous about taking out the radiator when there was still a fair bit of water running around. However, I hit the jackpot earlier on today. There's a vertical plastic covering about 9" long at the side of the house. It sits just under the gate post. I got it off eventually and sure enough it was the drain tap. Gone too dark to start the work so I'll have a go next weekend. Thanks for the tip on the washer.

Many, many thanks everybody for your help!

 

[Steady]

Think you're a bit confused.I know I am!You were talking in your original post about looking for the 'drain tap' so you could drain down your central heating.Sounds like the 'drain tap' you have found near your gate post is likely to be your external stop tap.All this does is control the supply of mains water to your property.Can you post a photo or clarify?What does this 'drain tap'look like?Think you might have draincock and stoptap mixed up.

 

[Forlopp]

Thanks Steady,

Better to be certain! Will take picture when I get home this evening and post it up.
Many thanks!

 

[Forlopp]

OK, got plastic housing completely off this evening. This definitely isn't the drain tap so it's back to removing the radiator I think.

Thanks for all your help!

 

[ArtfulBodger]

OK, got plastic housing completely off this evening. This definitely isn't the drain tap so it's back to removing the radiator I think.

Thanks for all your help!

Removing the radiator whilst full of water is not as difficult as you might think. Have a builders rubble bag ready, Shut off both valves, loosen the 3/4" union and catch the small amount of water that comes out. If you have floorboards, loosen the valve on the other side and then carefully lift the rad off its bracket and pivot to the floor, undo both sides and quickly orient the radiator upside down. Take it out of the house and empty it. Attach a 3/4" hoselock garden hose connector (as previously suggested) and put the hose on. Open valve and drain system. Replace the lockshield with one with a combined drain off. Replace radiator. Job done.

 

[Forlopp]

Thanks for that. Have been reading up on this. Going to buy a decent wrench and try this at the weekend. As soon as I have it out, I'm going to install a drain tap on this one and flush out the whole system.

 

[meldrew's_mate]

I have gravity-based open system with Baxi boiler and Myson pump (about 7 years old). System supports 8 radiators.

There is a spring loaded knob just above boiler which releases water into overflow pipe but I believe this will only clear water out of the radiators upstairs.

Could be a sealed system then?
Do you have a loft mounted feed tank?

What make/model is the boiler? Is there a pressure gauge on or near the knob you refer to? Either way it's about the same method to drain the system, just slightly more tricky to re-fill it if it's sealed.

 

[bab]

Hi ya meldrew. this is the longest confusing thread about a simple draifn tap iv read. o by the way i know there,s no F in drain.Ha ha. It did atart as an open system but it might of grown up it to sealed one by now.

 

[Forlopp]

All suggestions welcome, thanks Meldrew. System is open.