Baxi Bermuda

9 Oct 2012
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United Kingdom
Baxi Bermuda 401 and 552 back boiler are they suitable to be used with a sealed ch system ?

CH system is currently open vent and thinking of converting to sealed system as problems with CH expansion tank

Many thanks
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Baxi Bermuda 401 and 552 back boiler are they suitable to be used with a sealed ch system?
They can be converted, provided you fit the optional overheat thermostat kit. But whether it is wise to do will depend on how old the boilers are. The advice of Baxi should be obtained.
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Expansion tank I believe has faulty ballcock valve and water keep coming out overflow pipe, but its impossible to get to as it right in the highest point of the roof space, backed up against a wall and CW tank is directly in front of it.

To make it worse HW cyclinder is directly underneath both meaning you cant even get a ladder very close to it.

Utility engineer has suggested they can convert the open vent system to a pressurised system by installing a pressure expansion valve in the loft and eliminate the CH expansion tank but never mentioned about checking compatability with boiler, was until I looked on this site I realised have to make sure they got some kind over heat or pressure valve fitted.

Did wonder if system could be drained then might be able to relocate CH expansion tank, but does it have to be same height as the CW tank ?

If its ok to be lower then have a bit more room and might be able to lower the wall shelf its mounted on by 1-2 feet which would allow better access to it.

Is it ok to have CH expansion tank lower than CW tank do you know ?

Many thanks
By the rule of thumb it should be at least 1m above the top of the heating coil on the cylinder.


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