Making a hose for clearing airlock from radiator

[pateksan]

Hi, I got some useful hints with my first post last year so I’ll have another go.

It seems I have an airlock so I'm looking to have a go at the method shown in this video from plumberparts: I’m just trying to imitate his hose on the budget. I can see he's got the hose clipped onto a metal fitting, but I can't see what fitting it is. I’ve come up with the following:

1. Use the basic garden hose I already have Verve Freestanding Hose pipe set (L)10 m | DIY at B&Q

2. Reduce down to ½” using the blue bit of a hose connector Plastic Tap Connector

3. Use a hexagon nipple to plug into the radiator Brass Hexagon Nipple

Questions:

A. Can you guys see any issues with my proposed setup?

B. Will PTFE tape be enough to seal the connections or do I need something more than that considering I'm screwing a brass nipple into a plastic connector?

C. My cheap hose is quite thin, could this cause problems other than a longer time to clear the airlock?

D. The rad is upstairs at the front of the house, is there a reason why I shouldn’t run the hose to the bath rather than onto the front garden?

 

[Rob Foster]

just connect the hose from outside tap to lowest drain off
then turn on gently, check for leaks and go round bleed all rads lowest to highest/furthest, run pump on off . switch iff close drain off. done.
Rob Foster aka centralheatking

 

[pateksan]

Thanks Rob. That sounds like a different method to what James does in that video, and I have to admit I don't follow fully what you're saying. I don't suppose you're aware of a youtube video or website with some more detailed instructions for clearing an airlock your way? The plumberparts video is very popular but that could be because he's a good showman. How much worse is his method compared with yours?

 

[Best]

Thanks Rob. That sounds like a different method to what James does in that video, and I have to admit I don't follow fully what you're saying. I don't suppose you're aware of a youtube video or website with some more detailed instructions for clearing an airlock your way? The plumberparts video is very popular but that could be because he's a good showman. How much worse is his method compared with yours?

The method in the video is the safer and less likely to go wrong flushing to remove airlock method, especially for a diy person like yourself. It is using the system pressure.
You could just do same thing by removing a radiator that won’t heat and run each valve into a hose for a few seconds. (Might be only possibility if rad does not have 1/2” vents like in video).

Robs method is more for Professionals doing it using mains pressure and is risky if you don’t know what you are doing. You could risk over pressuring a system and doing damage or flooding.

Personally I would advise just running your heating system and turning all other rads and flow to cylinder (if you have a cylinder) for a few minutes to see if the rad heats. Normally this works

 

[pateksan]

Personally I would advise just running your heating system and turning all other rads and flow to cylinder (if you have a cylinder) for a few minutes

Thanks Best, just to double check, did you mean turning all other rads OFF?

 

[Best]

Thanks Best, just to double check, did you mean turning all other rads OFF?

Yes, all other rads and cylinder turn off.
Then just try running heating for a few minutes. Not the hose method!
I also try turning pump speed up, - say from speed 2 - 3 setting if old type pump, but again - JUST for a couple minutes to see if airlock clears.
Basically what I am saying is the pump will circulate the system water around the easy circuit and won’t push against the airlock unless the only loop possible is through that rad.
The obvious and the easiest solutions are best attempted first

Just be aware that sometimes it isn’t an airlock, but a blocked pipe.
I am assuming just like advice from the video that all other obvious possibilities were checked first like seized TRV, or balancing etc.

 

[pateksan]

Ok, I tried it once a while ago but illI give this another go. Cheers

 

[pateksan]

Seized TRV it was. I had considered it before posting this thread originally, but missed it on first inspection. I took the head off this radiator (bedroom), the pin wouldn't go any further in but I didn't know how much force was needed. After Best's latest post I also took the head off the bathroom TRV which is the same sort and works fine. The pin protruded by a very similar amount to the bedroom, I tried pressing it down, it went in a milimiter and got stuck there. Upstairs was now noticeably cold, so I did some more research and found more sources saying it's not really all that risky pinching the pin with pliers and pulling, so I did that on both TRVs and both rads were beginning to heat up in seconds. Thank you both for your responses once again.