Hi,
This Thread states Primus was taking over by ALDE?
You could contact them direct to see if they know the Specifications for your pump? Link to ALDE UK
very very few is the answer? In truth, the pump is an aid to thermal circulation rather than the sole means as in a domestic central heating systems.
The reason is the pipework is all on one level and does not need the aid of a pump to change floor levels.
Any lack of circulation is often down to air locks which disturb or stop thermal circulation
Further, Alde bought Primus who inturn are now owned by Truma, but Primus are still very much alive, just not in this country?!
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