Central Heating

[dannyo]

I fitted a grundfos 15-60 as i have 7 rads.

When you talk about fitting new valves do you mean the isolator valves?

I am sure pump is working and suspect I must still have some air in the system.

I can see no air coming out of the radiator just water?

How many litres would I need to vent off to ensure I have fully bled the system?

 

[Softus]

I fitted a grundfos 15-60 as i have 7 rads.

OK.

When you talk about fitting new valves do you mean the isolator valves?

Yes.

I am sure pump is working and suspect I must still have some air in the system.

Where do you think the air is, and why?

How many litres would I need to vent off to ensure I have fully bled the system?

There's no definitive answer to that - it depends on size of house, pipe length and pipe layout. If the pipework is badly installed, and without vents, and has become airlocked, then no amount of rad venting will clear it.

Did you fully drain down? If so, what was the condition of the water? Also, did you look into the header tank to make sure that you weren't about to draw debris into the system? For example, I drained a thatched cottage last week but looked in the F&E first and found five rotting mouse carcasses - it would have blocked every TRV if I'd drawn in bits of mouse flesh and fur, so I vaccuumed out the F&E and sponged it clean first.

 

[dannyo]

Condition of water is perfect as I added fernox chemical last year.
I did not check the header tank but it is well covered with lagging.
I have had the downstairs/furthest away rod hot at one stage. Thi did however go cold again due to me venting the rads and I could not get it to heat back up again?
May be it is arir locked?
Is there any way of getting air locks out of system?

 

[chr15]

Did you by any chance close the pump isolation valves when you changed the pump,and if you did have you opened them fully again? Have you put the pump on the right way around? Could your 3 port valve be faulty? Does your water heat up ok via the boiler? When did your heating last work correctly and did you have any work done on it? What make/model boiler have you got? Sorry for all the questions but need more info.

 

[dannyo]

Isolation valves are definately open. Pump is right way round and 3 port valve is working. Also water heats up for washing etc.
Heating last worked last winter and only thing I have done is change the pump. Boiler is a concord WRS ??

 

[Softus]

Condition of water is perfect as I added fernox chemical last year.

The two don't equate. For example, you can't just add an inhibitor to a filthy system and expect it to do its job. And it won't remove debris that's already in there. I don't know why you can't just look in the in the F&E cistern, and it's beyond me how how you can claim that the 3 port valve is working when you haven't yet got a working CH system.

Is there any way of getting air locks out of system?

Yes, if you have an air lock, but you be wasting your time and mine if you don't have an air lock.

Is the pump brand new? Even if the answer is yes it doesn't mean that it's working properly - the impeller could have fallen off, or one of the pump valves could be clogged, or..... just too many things could be wrong, and since it takes about 24 hours for you to answer each question we could be here for months.

 

[dannyo]

calm down. I have to try the suggested solutionss before I can respond.
I appreciate your help but don't really need to be told off!
3 port valave was fittted last year when I flushed the system and also added fernox which is why I am confident it is not a blockage!

 

[Softus]

calm down. I have to try the suggested solutionss before I can respond.

Maybe with some, but most of the questions I asked didn't require you to get out of your chair.

I appreciate your help but don't really need to be told off!

I respectfully disagree. For example, it's taken you four days to reveal the make and model of your boiler - this information is part of the set that you're asked to provide in the post in the sticky topic at the head of the P&H forum.

3 port valave was fittted last year when I flushed the system and also added fernox which is why I am confident it is not a blockage!

That's just mad - how can you be "confident" that any single component is working properly until you have a fully working system? It's this kind of closed-minded approach to problem solving that turns the whole episode into a frustrating lump of confusion. And if you think I'm telling you off, I haven't even started yet!

 

[dannyo]

OK I have the last radiator working now.
Do I just carry on and get the others going?

 

[suffolklad]

hi there are you bleeding the radiators with the system pump turned off? if not you wont get the air out. have you started at the bottom and worked upstairs bleeding only air not water. like the other guys said if you turn all rads offf apart from the one which is air locked the pump should push the air lock out

 

[dannyo]

I was bleeding with pump on.
How do I ensure it bleeds air only?

 

[suffolklad]

when you are bleeding the rads the pump, boiler must be off. you cant get the air out of the system when its being pushed around by the pump?

 

[dannyo]

thank you for your response, your help is much appreciated.

After closing off all radiaitors I have now been back around them all and bled each one. They all work individually and come up really hot.

I think they need balancing now though as only the two on the top floor work when the heating is on.

One otehr point is that my boiler seems to be struggling to heat up hot water and it does not seem to kick in when I alter the thermostat on the heating or hot water.

Is there any way of checking if the feeback to the boiler is working correctly?

 

[dannyo]

sorry one other point.

I have a bleed pipe just above the 3 port valve. I have bled this every day over the last week or so since I changed the water pump. It always seems to have plenty of air come out of it?

Is this normal? could this be why water is taking so long to heat up? What could the cause be?

 

[dannyo]

having bled this pipe a number of times with the 3 port vaalve in vaarious positions we now have loads of piping hot water for heating and washing!

My only concern is that every time I go back and bleed this valve there is a good amount of air in the riser pipe. Could this indicate that air is coming into the system or is it normal after a system drain down such as the one I did when changing the pump?