Vokera Compact 24 Combi - very low DHW pressure - help!!!

[delitubby]

Jamie

Thanks for your advice and clarity - all done sealed and sorted!!!

What a pesky little thing - the guy who installed it cam back and couldn't figure out what was wrong - good job he didn't charge me more than a cuppa!!

Thanks again

Matt

 

[chamisra]

the one at the back is the cold water supply to the boiler - undo the compression nut (ensuring the cold water is isolated) and remove the fitting inside the side of the boiler

Jamie

I can't hold a candle to you guys who have the skills needed

I'm a spark and as you can guess, need held by the hand ha ha!

The pipework entering the boiler from the right (main cold feed) i have removed and checked but from there they move into the crowded area of what i guess is the heat exchanger and i cannot get real access to them because of some electrical fitments.

Do you have (or could you take) a picture with a big fat arrow pointing to the pipe i need to disconneect and clean please, so i know i am not removing something i shouldn't be going near.

Many thanks and kind regards in advance
I'm sorry to ask, just i'm a poor paisley boy who is siht with plumbing

Craig (and heavily pregnant wife who needs a bath!)

 

[Chris Roberts]

FAO Gas guru

Hi. I am getting into this discussion a bit late! I have exactly the same problem with hot water flow with my Vokera.

I looked at the RHS of the heat exchanger. The rear pipe connects into the heat exchanger at the top with no obvious sign of any restrictor. At the bottom of the pipe (just above the square water inlet valve) is some kind of device and what looks like an electrical sender connected to the PCB. Is this the end that needs the centre part removing??

Chris Roberts

 

[chamisra]

Chris

See the pump mate with "Grundfos" written on it (or equivalent brand name)
directly at the back of that and on its right edge is a largeish copper pipe.

The sender unit you talk about i think is in front of it.

The pipe i am referring to has what looks like a bar attached to it to close off the water to that pipe.

Thats the nut you want to remove and pull the pipe away, inside will be a smallround white plastic one way seal. Thats the fella you want to remove.... just remove it, replace the pipe and try your water, if water pressure is good then just bin the thing... i have been running over a year with mine removed


the seal has a black rubber centre just to clarify.

The nut can be a bugger, just persist and you will get it mate

Chamisra

 

[Chris Roberts]

Hi Charisma

Thanks for that. I will check that out later this afternoon and get back to you. Your help is appreciated.

 

[Chris Roberts]

Thanks Jamie. I removed the flow restrictor and now the dhw pressure is great. First good shower for 3 months since I moved in.

Rgds Chris

PS. Flow restrictor is a very posh name for a 2p plastic ring that looks like the pull ring of a fruit juice carton

 

[logboy]

Hi

I have a similar problem to the commonly mentioned poor water pressure from a Vokera Compact SE boiler.

Have tried removing the flow restrictor but this hasn't solved the problem.

Boiler fires up then cuts out straight away (1-2 seconds) for both DHW and CH.

Any other suggestions please, is there a way of checking that the thermistors are working ok. Currently have no heating or hot water and getting a lot of earache(!).

many thanks
Tony

 

[tonybhoy]

Thermistors are about £10 each but sounds as though you have something common to both which is faulty. Possibly the APS or fan.

I have entire Vok compact 24 SE boiler for spares however the ignition PCB,Gas valve and APS may be faulty (there is an intermittent fault on the ignition side of the boiler) but I think it is the ignition PCB that is the culprit.

Boiler went to solid red led lockout on both heating and hot water and constantly required resetting.

Tony.

 

[logboy]

thanks for the quick reply Tony. I didn't think it'd be as serious as a complete new PCB as I'm not "currently" getting any red lockout indicators or the like. I just get the usual green light that all is well.

Is there any way of checking out the fan or APS myself or should i just bite the bullet and call out a Corgi engineer? The boiler is igniting and firing up ok but then cutting out again almost immediately and then firing up again etc etc.

I know what you mean about those circuit boards though, I've had to replace the internal fuse several times since it was installed and also used to wake up to the red light you mention in the past - should've heeded the warning signs really...

 

[tonybhoy]

On the older boilers there are two PCBs ,the main PCB and the ignition PCB which is plugged into the main PCB. On the latest SE compacts the main PCB does everything.

The ignition PCB is nearly £100 on it's own however I'm not entirely sure if the newer main PCB can be fitted to the older SE compact.

The APS is about £20 or less so I would down the thermistor & APS route you however should go for a fixed price repair from Vokera at £170 odd .

Tony.

 

[logboy]

ok cheers. Got someone calling on Monday so I'll keep you posted.

 

[logboy]

Got it sorted eventually. First changed the main PCB but to no avail, then changed the ignition board.

All fine now apart from the £200 hole in my pocket!


Vokera fixed price repair would have been the better option but would have had to wait over a week for them to call out.

thanks for your help anyway.

 

[colinc57]

Cheers guys ,

had a 1litre per minute output, and not firimng on DHW only ( so hot water only when Ch also on)

having tested water pressure at various points I assumed it was blocked somewhere in heat exchanger-
but having found this thread just removed the blue flow resistor, and no all is great ( even used the old cardboard washer at moment)

should I try and get a new resistor , or is it more trouble than worth?

 

[andynumpty]

Can I just check, if the hot water flow restrictor is removed this will increase the amount of water flow. This will mean that the inlet tap will have to be closed more to compensate for the extra water flowing through the heater. What is the benefit in that?

Thanks.

 

[andynumpty]

Any one?