I bought a "Drain Easy" Device, made by Drayton, which is designed to allow one to change Heating valves, pumps, radiators, etc., without draining down the system and losing your Inhibitor.
Working on the basis that the inhibitor costs over 10 quid this tool pays for itself (also around 10 quid in B&Q) at the first attempt.
It consists of two tapered rubber plugs connected by string. You put one plug in the expansion tank outlet hole and the other in the overflow pipe over the same expansion tank. It will fit 15 & 22mm.
After that you can (and I have ) take out the pump/TRV/etc with less than a teaspoon full of drip. I just used it to change the 3 way valve here.
You have to remember to remove the device before firing your boiler up (wonder why!!!)
Also you need to check for air locks after use!
Pretty fine tool though..Can't recommend it highly enough.
By the way, I have no connection with anyone in the manufacturing or selling of any product...I'm a retired old duffer.
Working on the basis that the inhibitor costs over 10 quid this tool pays for itself (also around 10 quid in B&Q) at the first attempt.
It consists of two tapered rubber plugs connected by string. You put one plug in the expansion tank outlet hole and the other in the overflow pipe over the same expansion tank. It will fit 15 & 22mm.
After that you can (and I have ) take out the pump/TRV/etc with less than a teaspoon full of drip. I just used it to change the 3 way valve here.
You have to remember to remove the device before firing your boiler up (wonder why!!!)
Also you need to check for air locks after use!
Pretty fine tool though..Can't recommend it highly enough.
By the way, I have no connection with anyone in the manufacturing or selling of any product...I'm a retired old duffer.