Problems with new heating.

[hyside]

I have just replaced the old existing conventional boiler with a Biasi 32 Compact Combi boiler. Also have a hot water cylinder running off the boiler so we can have pumped hot water. It's fitted with a Siemens 3 port valve. The problem is the radiators downstairs don't get hot and the hot water cylinder and hot water from the taps gets far too hot. I have powerflushed the system and changed the downstairs radiators as someone suggested it could be a problem with sludge/blockage. I have also bled all the radiators and balanced them. This worked to a point but I had to turn the upstairs radiators down so low from the lock valve that all the radiators were barely warm. I have also replaced the 3 port valve for a new one as it seemed the hot water for the radiators is by-passing this valve and instead of going downstairs is filling the hot water cylinder instead. Even with the thermostat on the tank turned down to zero, the hot water cylinder is still too hot to touch and the hot water too hot to put your hand under. Could this be a wiring issue? Help, Help, baby on the way in two weeks and having a breakdown! Thanks

 

[sloppytom]

you wrote a combi down is this correct, or have you installed a conventional or a system boiler. combi boilers shouldnt have cylinders fed from them. need a drawing of how your system is piped up really.

 

[DP]

Why should combi not be connected to a cylinder. I think it makes perfect sense. When combi goes belly up, cylinder still gives you hot water, that is if the immersion heater is wired and ready for use.

 

[gavinda]

so how does the cylinder recieve its water? from the heating circuit or from the domestice draw off

 

[GPlumb]

so how does the cylinder recieve its water? from the heating circuit or from the domestice draw off

The usual way. CWSC or the mains.

 

[Softus]

Why should combi not be connected to a cylinder.

Because the entire point of a combi is to eliminate stored water, both hot and cold.

I think it makes perfect sense.

In that case you're using an entirely different definition of the word "perfect" to everyone else.

When combi goes belly up, cylinder still gives you hot water, that is if the immersion heater is wired and ready for use.

That's also true of any boiler, and of any cylinder. Nothing to do with it being a combi.

 

[raychmike]

you wrote a combi down is this correct, or have you installed a conventional or a system boiler. combi boilers shouldnt have cylinders fed from them. need a drawing of how your system is piped up really.

As a great Welsh singer once said "it's not unusual". As he states in the post he wants pumped hot water, maybe the guy just can't live without his power shower. Ok so it's not energy efficiency as we'd like and I would advise against it but if your running your heating and have the option to heat a tank of water for storage at the same time then why not. Only last month we connected a combi to an OSO unvented cylinder. Ran the combi's HW to all the hot taps in the house. Then connected the 150 gallon tub and all the shower outlets bar one to the HW on the cylinder. Again not energy efficiency at it's peak but just imagine filling that tub from a 28kw combi's HW flow rate. With all the sums added and several phone call's to the cylinder manufacturers this was decided as the most efficient way to fill that baby.

 

[simond]

The answer to the OP's question is that he's wired it up wrong, by the sound of it.

If he 'didn't want the stress' he should have either;

1. Kept it simple or
2. Got a registered and experienced professional to do it

 

[gavinda]

so whos gonna quote to wipe his bum then


10,000,000 dollars