Renewal of SIPs

Thank you. But we aren't residents, just own a small casita here and come for short holidays, so we have to renew our SIPs every six months. We don't know the guidelines for visiting the Centro de Salud for non essential reasons. 

Ray, I'm not sure that your advice applies across all communities. I am under 65, live near Pego in Alicante province, have residencia and have been able to access the Spanish healthcare system via a temporary SIP for the last year. It was issued by my local Centro de Salud and I'm pretty sure it was AFTER I applied successfully for residencia. To obtain it, I had to produce passport, padron certificate and EHIC card. I have had hospital appointments with a consultant using the card, arranged by my local GP, I have also had a prescription for blood pressure medication ongoing using the card. Like the OP, my card expires soon, and I'm wondering how to renew it, because I believe from someone else's experience that responsibility for issuing the cards has shifted to the Social Security department in Denia.

I believe quite a few temporary SIP cards have been issued more as a convenience for the Centro de Salud and that is why it is temporary, almost confirming the need to do something within the time given to sort out long term health cover.
You are only entitled to a SIP if you have a UK state pension or are in receipt of an exportable benefit. If you do not fit into either group you are not entitled to a SIP and the healthcare you received was more on the back of your EHIC than your entitlement to continued Spanish healthcare.
What you need to do now is arrange private medical insurance for a year after which you can apply to the Convenio Especial until you get your pension.

I am a pensioner. But thank you. 

I was replying to HerefordJack but as you are not resident you are not entitled to a SIP card and your only access to Spanish healthcare is the EHIC or travel insurance. You may have been issued with a temporary SIP card, more for the convenience of the local Centro de Salud but it in no way infers entitlement to continued free healthcare.

Ray, I'm still confused. I do have private health insurance, which was used to obtain residencia, but I want to continue using the health system for continuity in the case of the consultant, where I have another appointment in July, and my ongoing pharmaceutical prescription for an unrelated issue. Are you saying I can't?

How do I get a S1 I’m a pensioner and I’ve just got my health insurance , but do I need both ?

You need to contact the Overseas Healthcare team at DWP Newcastle.

https://www.gov.uk/guidance/healthcare-in-spain-including-the-balearic-and-canary-islands 

Having private health insurance would be an optional extra the same as in the UK.