AIR LOCK ON FILLING UP AFTER WATER SYSTEM DRAIN DOWN

[g1]

Over winter I drain the water system in the 'van down - tank drained, taps left open. I'd like drain the tank down before leaving a site too.
But, when I refill the system again I always seem to get an airlock. The pump fills the tank and then stops. Putting a tap on I can hear the pump again.
The kitchen tap flows fine but the hand basin tap and shower just splutter. . I can hear a lot of gurgling.
After draining and filling several times and after a lot of gurgling and spluttering it eventually rights itself but I don't know why. It's all very hit and miss.
Are there any tips about filling up to avoid this problem, please?
Thanks, g

 

[TerryIvybridge]

hello g. I used to have this ploblem with a Bailey we had. If I remember correctly, I just opened the cold tap in the bathroom slightly whilst filling the system? might have been the hot? Hope this helps. Terry.

 

[johnandrew70]

I had the same problem, i have since been told by a friend that he always keeps the hot water tap open on the sink furthest away from the tank while the tank is filling, that bleeds any air out of the system,
I have to admit i have not tried it yet so cant say if it works or not, someone else on here might be able to tell me if its right or not.

John

 

[ProfJohnL]

If you do a complete draindown, then that will also mean the hot water tank will also be emptied. On refilling, the pump has to refill the hot water tank also. These tanks need to be able to vent any air as it fills, and this is done by opening the hot taps. when the hot tank is almost full the air will splutter a bit through the taps. just continue until you get a full flow of water.

 

[g1]

Thank you gents for your advice.
I'll try it at the weekend.

g

 

[Ian4624]

Hello g,
You may have read my thread about my troubles re-filling the system on my old Bailey and the pump not switching off.
The Bailey handbook instructs to open a cold tap then switch on the 12v supply to the pump. When water flows from the open cold tap the system is ready for use. I don't think that that is entirely true as in my experience over the last two days the hot water tank does not fill properly as there is no where for the expelled air in it to go until a hot tap is opened. It takes considerably longer for water to flow from the hot tap as the pump as to pump 9 litres of water into the tank to fill it before any water flows up to the tap, whereas it only has to fill the length of the pipe to the cold water taps. Whilst I've been messing on I've had the seat cushion above the hot water tank removed and sometimes it is possible to hear the water filling up the tank.