Hi Guys, my vokera linea 24 is alternating hot and cold when i run a hot tap. I have the selector switch on heating and domestic hot water and i have the temp turned up to max but when i turn on the hot tap the water heats up to 52 degrees then the burner cuts out at 52 degrees and water cools down to about 27 degrees then the boiler fires back up and the water gets heated to 52 degrees again and then the burner cuts out again and the temp drops to about 27 degrees again and so on again and again. Also i have noticed when the temp drops to about 27 degrees and the burner kicks in again i have noticed when the temp reaches 35 degrees the needle on the water pressure gauge starts to fluctuate and i can hear a small noise from the boiler but as it heats up more it settles down.
I did that test that i read from a previous post where i turned the temp up to max and i ran the hot tap and as soon as the burner cut out at 52 degrees i turned the black lever underneath the boiler to the right hand side fully anti clockwise so it was looking downwards so it turned off the hot watter and the temp shot up to 94 degrees. So my guess is that the DHW heat enchanger is blocked and needs replacing, would i be right in saying that? Also whats your thoughts on the pressure gauge needle fluctuating and the noise, i have noticed the CH pressure is low would this have anything got to do with that.
Oh yea just one more thing i noticed when i turned the selector switch over just to hot water ( i know this does not make a difference) the very same thing happends but the odd time as the temp reaches 52 or so degrees and then when the burner cuts out and the temp drops the green light flashes red just for a second at about 40 degrees, but no fault code is displayed and the temp just drops a small bit more before firing again.
I did that test that i read from a previous post where i turned the temp up to max and i ran the hot tap and as soon as the burner cut out at 52 degrees i turned the black lever underneath the boiler to the right hand side fully anti clockwise so it was looking downwards so it turned off the hot watter and the temp shot up to 94 degrees. So my guess is that the DHW heat enchanger is blocked and needs replacing, would i be right in saying that? Also whats your thoughts on the pressure gauge needle fluctuating and the noise, i have noticed the CH pressure is low would this have anything got to do with that.
Oh yea just one more thing i noticed when i turned the selector switch over just to hot water ( i know this does not make a difference) the very same thing happends but the odd time as the temp reaches 52 or so degrees and then when the burner cuts out and the temp drops the green light flashes red just for a second at about 40 degrees, but no fault code is displayed and the temp just drops a small bit more before firing again.
