Only luke warm water from Pulsacoil 2000

My son owns a flat that is fitted with a Pulsacoil 2000 PC145 that has been working fine since he brought it 7 years ago. Last week the bottom - off peak- immersion heater failed. I replaced the heater and temporally connected it to the day time switch. The heater worked fine and the thermostat operated correctly. However according to the tenant the water is now only very warm, not hot as it used to be. The storage heaters all come on so the Economy 7 appears to be working. The pump works when a tap is run and there is plenty of water in the header tank. Any suggestions please ?

Set the stat up if not a Gledhill one (they are set and sealed at 76c.
Also make sure the unit heats up for a good time as in hours
Mike

Mike

Many thanks for this advice. The tenants report they now have water that is warmer than it was but only warm enough to wash hands under a running tap, not hot enough to shower as it used to be.From your comments and other sources I have decided to replace the Econ 7 heater with a genuine Gledhill part as they are set to a higher temperature and have a larger heater surface area. Hopefully this will resolve the problem. I will keep you posted !

New heater sourced from Gledhill, installed and success plenty of hot water again and happy tenant !
I would recommend anyone not to bother replacing the immersion heaters in these units with cheap off the shelf heaters as that are clearly not up to the job and are a false economy as they clearly do not heat the water to the correct temperature for the unit to work correctly. I was impressed with Gledhills service, heater ordered about 10 am, delivered 8.15am next day and considerably cheaper than on line or ebay.
Thanks for your advice Mike.
As my Dad used to say ' A little help is worth a lot of sympathy '!