Question about Air Conditioners

2 Answers

Vaillant boiler (VCW GB 221) not heating up water or heating although the pilot is lit. Pump is heard working okay but there is small drips of water underneath boiler. Any idea's?

Posted by on

  • saisruti Mar 25, 2009

    Ihave Vaillant VCW GB 221 H - all of a sudden started to make knocking noise (it sounds like a motorbike engine) - is it the main pump or something else? please email solution if you know =info@saisruti.org.uk thank you

×

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Governor:

    An expert whose answer got voted for 20 times.

    Corporal:

    An expert that has over 10 points.

    Mayor:

    An expert whose answer got voted for 2 times.

  • Contributor
  • 13 Answers

The movement of the diverter valve is critical on this appliance, and is located on rear right of the boiler, when hot water is turned on, theres are two microswitches, which must break (they both close in Central heating mode), if pump is running, it is recognising the hot water demand, check microswitches are breaking, if not, it tends to be a defective servo valve (located above the water valve), or a blocked/ restricted control line (small copper tubes which connect into the servo valve)

Posted on Mar 03, 2009

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Drips of water obviously indicate a leak - locate the leak - althought it could be condensation unlikely & that would be in more than one place around the boiler.


obviously as it may sound - is the gas meter is a pre-paid one - check there is plenty of credit & the meter is ON and not on emergency credit

boilers are like women - not always easy to figure out and why they suddenly go wrong when all has been well !

leaks mean bar pressure dropping - so check for leaks and check if water is leaking from the pipe on the outside wall - problem could be with the Pressure Relief Value (PRV) not working properly - hence not allowing the system to maintain pressure and releasing it - so check bar pressure

possible problem with expansion tank?

or Printed Circuit Board - so check by topping up the system - by turning on top up tap - see if the bar pressure will go up to maximum - if it does close top up tap before maximum bar 3.5 - see if any water leaks outside - if so - monitor the pressure gauage and turn on the hot taps full
the the gas burner lights up - some progress - atleast the gas value isnt at fault necessarily - if the burner stays on for a while at least 10-15mins - then atleast it's ok to assume the heat sensors, the heat exchanger and gas value are ok. -

now see if the bar pressures is falling - if it is - then probs with PRV - probably needs replacing.

these boilers are OLD however i have found them to be very reliable - there are newer more efficient ones on the markert but why replace an entire boiler if it;'s been very reliable ?

there is a temporarily solution around the PRV and that's to leave the top up tap partially on - the water may not get as hot but hot enough and your outside wall will get very wet until an engineer visits - good luck but get a professional in.


- if it's falling there's an indicator it's the PRV -

Posted on Jan 06, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Vaillant aqua plus combination boiler


First off, I'm not familiar with this particular boiler. I'm in the USA. I believe this is manufactured in the UK and may not be distributed here.
Second, and are you sure you needed to replace the blower in the first place?

Those questions really need to be answered before making any accurate remote diagnostics. This is a pretty complex piece of equipment with costly replacement parts. Some diagnostic and/or service work should be left up to a professional in your area if you're really not sure of what you're doing.

We all (or most of us) like to save money by doing our own repairs. If you feel confident about working on this further you can go to www.vaillant.co.uk to get manuals and service info online. This info will do you much more good than my guesses will. This unit has a diagnostic/control board that will display most faults if you know how to use it. I looked at some of the info online. They have pretty good stuff available to you if you know how to use it.

After all saying that, it "could" be the pressure switch not closing after the fan starts. You didn't say whether the new fan is starting or not. On a call for heat (or hot water) the fan starts (controlled by the main control board), the pressure switch proves the fan is running (and venting combustion gasses out of your home), it most likely has to prove water flow. If all the proving is confirmed, the ignition sequence will begin.....ignition, prove ignition, main gas valve opens, heats water, so on and so forth......

Now, if you still feel confident to work on this boiler, go to Vaillant's web site and read the manual(s). If you're not confident, call the heating man in your area. Just be careful with gas, electricity and hot water!!

I wish I could have given you more info to actually fix your problem, but I need more info as to why you changed the combustion blower to begin with. What WAS it doing? what IS it doing NOW and so on....

Good Luck to you! Let me know what you find out.

Bob
lainemech

Mar 18, 2014 | Air Conditioners

1 Answer

Hi can anybody help,i have a vaillant combi boiler and i cannot turn the heating off on the radiators can anbody help cheers!


If you they won't go off when your timer is off. There's a possibility it's clock keeping it on although its turned off, which is fairly rare. However depending in which model of Vaillant you have, if your boiler has a hot water pre-heat on it. Some models which have this the diverter was prone for sticking thus leaving the port for the radiators open when in hot water mode.

Oct 03, 2013 | Air Conditioners

1 Answer

Im calling for heat from the thermastat and control panel, the boiler light and and the fan is running, but no matter how many times i keep re trying the pilot and burner will not commence, is there...


I would check to make sure control on gas valve is in on position and pilot is lit if you have a standing pilot. If you have a spark or hot surface ignitor make sure they are trying to lit pilot. If you have standing pilot model and pilot lit is not on. Turn control on gas valve to off,wait five mins. then turn to pilot. Depress botton and try to light pilot. If it lights hold down for a couple of mins. then release.. If pilot stays lit turn control to on. If thermostat is calling for heat this should bring main burner on. If pilot does not stay lit then replace thermocouple. Hope this helps. Thanks

Nov 16, 2010 | Air Conditioners

1 Answer

When you turn hot tap on nothing happens to the boiler just cold water out of tap when heating switched on pump starts but does not ignite


I think you are working on a RV water heater.
Check the reset on the unit and turn your beakers off and on.
If you are working on a gas water heater is the pilot lit.
If you can get us a little more INFO we can help you better.

May 16, 2010 | Air Conditioners

1 Answer

The pilot light is out on our Apollo boiler and I can't seem to find anyway of putting it back on, its bloody freezing, we have no heating but hot water is fine, seperate tank.


Most likely it is the thermocouple. A 10.00 item at Lowe's or home depot. Easily removed and replaced. This devise is a safety device. It heats up to a certain temperature and the resistance changes back to the gas flow valve. After about 30 seconds of having the pilot on and the valve held down while lighting the pilot it should stay lit. If it does not, it is the thermocouple and has to be replaced. I did this on our apartmen'ts boiler a week ago and it works fine.
Hope this helped....
Kevin

Jan 31, 2009 | Air Conditioners

1 Answer

Clock on comi boiler


it may be the preheat setting on the boiler for the hot water circuit. do the radiators get hot when the boiler fires up with the time clock off ? if not then there is nothing to worry about if it is only on for a short time.

Jan 04, 2009 | Air Conditioners

1 Answer

Bosch greenstar 30 CDi - no central heating or hot water!


it sounds like the system was not cleaned properly when the new boiler was fitted. all new boilers need to have the pipework flushed to remove any debris scale sludge and flux from the system. this is now usually done by a power flush which is basically a big pump mounted on a big bucket and it washes the dirt out of the pipework and collects in the bucket. if this is not done the dirt will block up the small passages in the heat exchanger. i suggest the system is cleaned flush and the heat exchanger changed to help protect the boiler a filter should be fitted (for example a magna clean) if the company who installed the boiler is corgi registered then they are liable for the damages. call corgi for advice.

Jan 04, 2009 | Air Conditioners

1 Answer

Ariston micro genus combi boiler central heating works okay but domestic hotwater fails to rise but burners seem to be lit and the boiler doesnt appear to cycle dhw temp gets to about 30 degrees instead of...


having found a circuit diagram, realised that the divertor valve was electrically operated.i unplugged this then unclipped the motor from the valve body,the diverter valve is spring loaded and once i'd removed the motor the spring raised the valve to divert water through the dhw heat exchanger,giving us hot water but no heating, if i refit the motor the problem comes back heating no dhw.ordered new motorised valve assembly £30 next day order .
this was a simple fix without having to drain the system down.

Dec 07, 2008 | Air Conditioners

2 Answers

Hi,i have a vaillant turbomax combi boiler,the radiator side is working well but when running hot tap the boiler kicks in for about 5 seconds ,hot water starts to flow then boiler cuts out,water runs cold...


Which turbomax, as there a two different models. The more modern one, with the brass CPL diverter valve, located at the front left of the boiler, was very prone sticking & jamming, this would restrict flow through the hot water circuit in the boiler, and cause cycling. Vaillant actually modified the diverter. You can identify, if it is the old type, as there is a very small hole in the middle of the diverter on the old ones, probable no more than 1mm-2mm wide. The modfied one, is much bigger approx 5mm wide. If old type, replace as this usally sorts the problem

Nov 23, 2008 | Air Conditioners

1 Answer

Vaillant Ecotec combi boiler - radiators working but no hot water flow to taps


David,

The fact that you're getting a little burst of domestic hot water suggests that the boiler is capable of circulating hot primary loop water through the heat exchanger, but doesn't necessarily do so when it needs to.

What seems to be lacking is a recognition that domestic hot water is now being drawn off, and that the boiler needs to fire up and divert the primary flow through the heat exchanger.

A good place to start might be the flow switch (usually in the bottom of the boiler, where the cold water supply comes in) or the electrical connections to it.

A.

Oct 05, 2008 | Air Conditioners

Not finding what you are looking for?
Air Conditioners Logo

Related Topics:

1,976 people viewed this question

Ask a Question

Usually answered in minutes!

Top Air Conditioners Experts

Dan Webster
Dan Webster

Level 3 Expert

8147 Answers

Bill Long

Level 3 Expert

577 Answers

Tim Whalen

Level 3 Expert

3056 Answers

Are you an Air Conditioner Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...