HOW TO EMPTY HOUSE COMPLETELY OF WATER ?

[worcesterman47]

hi, i need to replace at least 2 or 3 gate valves in my hot water tank cupboard..as i have no idea which valves contol what..i need to completely drain all water from within the house..i know i can turn off mains tap..and then i can totally empty hot water system..but how can i definately drain central heating system ? there are no drain points on radiators & the " header tank" in loft is in an almost impossible position to access & manually empty it..i would appreciate ANY advice to definately make sure all water is removed from the house before i remove & replace non working gate valves ( when i say non working i mean i cannot open or close them..they are stuck solid..i have tried things like WD40 & it has no impact at all..so please any advice would be greatly appreciated

 

[Strachan]

If you`ve access under the ground floor boards, just cut a heating pipe and let it drain. Start upstairs after 10 mins or so opening the bleed screws on the radiators to allow air into the system. Then do the same downstairs. Make sure the f/e tank is isolated too. If it doesn`t have it`s own isolation, best to put one in while the water`s off. Watch out for air locks, especially on the coil in the cylinder when re-filling.

 

[JohnD]

If you lift the floorbaords (where they show signs of having been cut before) there is a slim chance you will find a drain off. Perhaps next to the back or front door.

This would be a good time to fit some rad valves with drain-offs on the ground floor rads next to an external door so you can put a hose outside.

BTW you only need to drain the water up to the level where you are going to cut the pipes. It doesn't matter if there is water in parts below that level, it is not going to run uphill and leak out.

If you buy a longish Washing Machine Filler hose you will probably find its screw-on end fits on a radiator valve, so if you drain one ground floor rad by turning off the valves and slackening them, you can lift the rad out of the way and put the hose on the valve. You might also be able to get a fitting that goes on your garden hosepipe.

If you are going to drain the system this could be a good time to give it a chemical clean and rinse, and use inhibitor when you refill.

 

[worcesterman47]

hi again..thank you for the replies.. but there will be no drain tap on lower radiators (under floorboards ) as the floors are concrete..as for removing floorboards & cutting pipe on first floor ( firstly i would not know which pipe was for the radiators etc & secondly i would have to remove carpets then floorboards to cut pipe...i really do not want to have to do that...stupid question coming up now possibly...could i not turn off water at the mains then totally drain hot & cold water tanks..then turn off 1 radiator at ground lever then remove radiator from the wall then re-open valve from wall pipe & wait until the pipes empty ..is that a plausible option ?..thanks yet again in advance

 

[Ron Gamma]

If you can only drain from a radiator on the ground floor then try not to disturb the joints unless you can avoid it. You could use the bleed screw as the drain point instead if you only need to empty the upper half of the system. Don't forget to open one upstairs as well to speed the process.

It is going to be a relatively slow process anyway. I use an empty 1litre ice cream tub under the rad to catch the run-off and transfer it to a bucket to cut down on trips to the sink.

If the drain tap is not on your rads do you have an internal soil stack ? Sometimes the c/h feeds are in the same box section as the soil pipe and that is where they hide the drain taps on the ground floor.