hot water heats up suspiciously quickly

12 May 2014
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United Kingdom
Hi Guys
I'm not sure if I have a problem!!!!
I have replaced my Potterton ep3000 programmer with a centaurplus C27 programmer. HW and CH are perfect when on together, but when I have HW on alone it only seems to heat for a short amount of time, I see the water temp on the boiler rise from say 50 up to the pre-set temp of 60 in just a few minutes. I have a gravity fed HW water pumped CH. Y plan system. I used terminals 1,3 and 4 on the C27. I have removed the link which makes my C27 HW, or HW+CH. It all switches on and off perfectly. My boiler is a glow-worm flexicom with hot water tank, no room stat in the system but do have a stat on the hot water tank and stats on the rads. It was all perfect before I changed the (faulty) programmer. It seems to heat the water bit by bit
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If you have a y plan system then it will be classed as fully pumped, you should not have removed the link from the back of the programmer.
thanks for a swift reply.......
Reading the paperwork for the C27 I removed the link so that my system would only run HW or HW+CH. The way I read it, it if I left the link in I could have CH or HW or CH+HW. My old system with the potterton programmer only gave me HW or CH+HW.
If I have a fully pumped system would I have one pump?
I do have a pump it is a grundfos type ups 15-50x18 Mk2.
I guessed that I have a gravity HW (wrongly it seems?)
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yes it does
Ive just seen wot you wrote at the bottom of the photo.
I have to find a link to replace the one I threw away.
Do you think that'll fix my problem?
What is happening with my hot water why do you think it only seems to heat it bit by bit ?

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