gravity hot water

[quality]

Had a mare today with a old solid fuel system. Pumped return and gavity hot water. I tried all I know to clear the air lock from the hot water cicuit with no success.
In the end I put connection on the flow and return ( AT THE CYLINDER) with a valve in each to force water down the circuit to ensure it was primed.
It worked in the end but just wondered what you guys resort to with normaly easy overcome problems.
ps It was a 3 story house with one hell of a gravity pipe run

 

[Billy Bob Bob]

a axe

 

[diamondgas]

Well 'quality' what I've found in my journey as a gas engineer with gravity systems is that if you have an airlock in the return pipe no amount of 'boiling' will remove it!

What I use to do, I say use to because it's been some time since I had the problem; this only works with the drain point on the return at the boiler bye-the-way! Anyhoo's, what I'd do is .........

Okay this is for the professional only right...... none of you armatures trying this one!

Okay with the drain hose on the return, primed and ready to open, I'd boil the backside off the boiler and open the drain-off fully!!! Hoping that the cold feed from the header tank would push the air-lock out! Usually the cold feed and vent were situated at the cylinder!!!

It works, most times!

Obviously with limited experience i would not recommend this as it could scare the poop out of anyone at home, including yourself!!!

 

[Billy Bob Bob]

Well 'quality' what I've found in my journey as a gas engineer with gravity systems is that if you have an airlock in the return pipe no amount of 'boiling' will remove it!

What I use to do, I say use to because it's been some time since I had the problem; this only works with the drain point on the return at the boiler bye-the-way! Anyhoo's, what I'd do is .........

Okay this is for the professional only right...... none of you armatures trying this one!

Okay with the drain hose on the return, primed and ready to open, I'd boil the backside off the boiler and open the drain-off fully!!! Hoping that the cold feed from the header tank would push the air-lock out! Usually the cold feed and vent were situated at the cylinder!!!

It works, most times!

Obviously with limited experience i would not recommend this as it could scare the poop out of anyone at home, including yourself!!!

pulling the stat phial works as well boil it to death obviously you cant do that with solid fuel

 

[Puddle]

I miss all those bad,time consuming air locks you use to get in the old systems,back filling,turning pumps round,removing boiler thermostat,pulling system water through drain off's...... happy days

:75:

 

[quality]

Well 'quality' what I've found in my journey as a gas engineer with gravity systems is that if you have an airlock in the return pipe no amount of 'boiling' will remove it!

What I use to do, I say use to because it's been some time since I had the problem; this only works with the drain point on the return at the boiler bye-the-way! Anyhoo's, what I'd do is .........

Okay this is for the professional only right...... none of you armatures trying this one!

Okay with the drain hose on the return, primed and ready to open, I'd boil the backside off the boiler and open the drain-off fully!!! Hoping that the cold feed from the header tank would push the air-lock out! Usually the cold feed and vent were situated at the cylinder!!!

It works, most times!

Obviously with limited experience i would not recommend this as it could scare the poop out of anyone at home, including yourself!!!

I tried the dry boil trick with no luck but as you say it normaly works but definatley not for the inexperienced.
I have never come across a system with such a long gravity run before and started to doubt weather it had actualy ever worked

 

[diamondgas]

Thing is with solid fuel I'd imagine it'll take some air-lock to stop it working! That's why I wondered if it was in the return pipe? They're always a mare to get shot of! You'd have to litterally put a pump on the gravity circuit in reverse to push the mother out!!