Constant air in central heating system

[Baldy Geoff]

I used to have a duel fuel system at home where I had oil heating and a multifuel stove with back boiler linked up to the heating system and they worked fine together for years. Around a month ago I got the oil taken away and a new worchester gas boiler installed. From this work was carried out there has been constant air in the system and no matter how much I release through the rads it just keeps coming. I am limited in my plumbing knowledge and can tell you that I have 2 pumps, one beside the stove downstairs and a second one upstairs linked to the gas boiler. There also are now what looks like 2 vent pipes in the attic that was put in with the gas and I've a header tank in the attic as well. I'm off the opinion that this system has to be drawing air in and would really appreciate any advice on this issue. Thanks in advance, Geoff.

 

[king of pipes]

Some pictures would help but you seem to be on the right track cold feed the postion of vent pipes and pumps are critical to avoid pump over and air ingress . cheers kop

 

[Baldy Geoff]

Some pictures would help but you seem to be on the right track cold feed the postion of vent pipes and pumps are critical to avoid pump over and air ingress . cheers kop

 

[Baldy Geoff]

These 3 pictures are the gas boiler, the vent pipes in the attic and the pump built into the wall cavity in the stove downstairs. You've made an interesting point regarding the positioning of certain elements although I wouldn't understand what works and what doesn't in that regard. The gas boiler you see is in a cupboard at the top of my stairs and it is piped up into the roofspace above, with the vent pipes approx 10 feet down from the pump beside the f & e tank. Thank you for taking the time to help Kop.

 

[SimonG]

How are they linked together?

 

[Baldy Geoff]

Good question Simon. I know the flow and return was taken from the stove and piped upstairs into corresponding pipes in bedroom upstairs. The pipes feeding the gas boiler have been taken from the hot water cylinder in the adjacent bedroom, go directly up into the roofspace where the 2 vents are fitted. Then teed off around 10 feet and down into the boiler. Hope this helps, excuse my poor understanding of this and thanks.

 

[Baldy Geoff]

The gas men stop ended the 2 pipes in the pic under the floorboards from the previous oil tank feed. Is this the correct procedure?

 

[Baldy Geoff]

Kop has suggested the positioning of cold feed, vent pipes and pump are critical in terms of air intake. Is there a rule of thumb regarding this? My last throw of the dice will be to fully drain the system and refill it again though if there is another underlying issue it would prove fruitile to do that.

 

[SimonG]

Might be better to actually get somebody to visit. Although pictures paint a thousand words you can't actually beat coming eye to eye with it.
Post your location, there maybe somebody on here who can visit and give it the once over.

 

[Rightjob1]

Zone valves and a solid fuel boiler stove?!

 

[Best]

Those manual vents are irrelevant and are only to remove air from those pipes on system fill up.
The thermostat operating fire pump is on wrong place, - should be on return at cylinder.
Whoever did the gas boiler is responsible for the air in system, but connecting into dual heating systems is a bit of a minefield and rarely are dual systems actually properly designed or piped.
I assume the cylinder has 2 coils?

 

[king of pipes]

Hard to tell from the pictures Geoff how the two systems are joined ? the vents and cold feed should be on the negative side of the pumps the pump on the boiler is on the return into the boiler where does the vent and cold feed connect probably a design error there somewhere. Cheers kop

 

[Baldy Geoff]

Those manual vents are irrelevant and are only to remove air from those pipes on system fill up.
The thermostat operating fire pump is on wrong place, - should be on return at cylinder.
Whoever did the gas boiler is responsible for the air in system, but connecting into dual heating systems is a bit of a minefield and rarely are dual systems actually properly designed or piped.
I assume the cylinder has 2 coils?

 

[Baldy Geoff]

Not sure about the coils to be honest. What I have recently noticed is that the thermostat connected to the downstairs stove when turned off and on seems to turn the gas burner off and on as well. Don't think this is right.