ᐅ MAG installation questions

Hello,

my name is Markus, and earlier this year my family and I fulfilled our dream of owning a house. In spring, the electrical installation suddenly failed us, and due to the storage heaters, it got a bit chilly at first. Now we are almost finished with the electrical work, and a few days ago the pellet boiler was delivered. A friend was originally going to help me with the installation, but he is now unable to assist due to an accident.
Soldering the pipes seems like the least of my worries since I have almost completely replaced the water pipes as well. The pipe layout plan is already prepared, but we forgot to include the expansion vessel (MAG). I have now roughly pre-installed everything between the buffer tank and the boiler. The expansion vessel is an 80-liter (21-gallon) unit and should be installed on the return line before the return flow riser.

Here are my questions: Does it matter if the expansion vessel is connected with an 18mm (3/4 inch) copper pipe, including two sections of 1.5 meters (5 feet) length and a 90° elbow, or is that setup acceptable?
Currently, the connection on the expansion vessel is at the bottom, and I also have a shut-off valve. However, when I bleed the system, there is still some air trapped in front of the membrane. Does this air cause any problems, or does the connection need to be from the side to ensure it is free of air?

Hello,

Does no one know, or does no one want to help me?

Your question is probably too specific for a general homebuilding (non-professional) forum.

MarkusS. schrieb:
does nobody know or does nobody want to help me?

In a forum mostly made up of people planning to have a house built, you will find all kinds of trades, but rarely heating installers.

Yes, there is at least one :-)

For the MAG, the length of the pipe and the number of bends installed do not really matter. If possible, the pipe should be a 22mm (7/8 inch) diameter. It also doesn’t matter whether the connection is at the top, bottom, or side.

Hello

Great, and thank you, that is at least something. However, the main issue with the air, when the connection is made downward and the resulting improper venting, has unfortunately not yet been addressed.