Hello,
I'm trying to arrange a simple internal pump head swap on my 11 year old Worcester Greenstar 24i Junior (in Oxfordshire).
Current pump: Grundfos/Bosch UPS 15-60 CHG (59596500) – recently failed, 11 yrs old
Replacement: Grundfos UPS4 GO 25-65 130 – head only
Confirmed by: Grundfos GO Replace app (official match – report attached)
System condition:
Recently flushed + inhibitor
Internal condensate siphon trap spotless
Pressure stable: 1.0–1.5 bar cold → 2.0–2.5 bar hot
New expansion vessel fitted
No pipework, no complications
Issue so far:
Most local engineers insist on Worcester OEM only or claim UPS4 GO is for external use only,
despite Grundfos confirming direct internal head fit (130mm, 4 screw, same electrics).
Looking for:
Gas Safe independent who’s fitted Grundfos heads in old combis
Happy to work with customer supplied, manufacturer verified part
Attachment: Grundfos GO Replace report (PDF)
If anyone local to Oxfordshire has experience with this pump, or can recommend someone suitable, please let me know.
Thanks
I'm trying to arrange a simple internal pump head swap on my 11 year old Worcester Greenstar 24i Junior (in Oxfordshire).
Current pump: Grundfos/Bosch UPS 15-60 CHG (59596500) – recently failed, 11 yrs old
Replacement: Grundfos UPS4 GO 25-65 130 – head only
Confirmed by: Grundfos GO Replace app (official match – report attached)
System condition:
Recently flushed + inhibitor
Internal condensate siphon trap spotless
Pressure stable: 1.0–1.5 bar cold → 2.0–2.5 bar hot
New expansion vessel fitted
No pipework, no complications
Issue so far:
Most local engineers insist on Worcester OEM only or claim UPS4 GO is for external use only,
despite Grundfos confirming direct internal head fit (130mm, 4 screw, same electrics).
Looking for:
Gas Safe independent who’s fitted Grundfos heads in old combis
Happy to work with customer supplied, manufacturer verified part
Attachment: Grundfos GO Replace report (PDF)
If anyone local to Oxfordshire has experience with this pump, or can recommend someone suitable, please let me know.
Thanks
Attachments
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