DEfective Diverter Valve?

[Catceefer]

Can anyone help? My hotwater heats properly, but the radiators take a very long time to warm up and rarely get properly hot. They have been bled and the pump is new (the old one failed).

If I turn the hotwater off on the timer so that just the heating is on, the radiators heat up quickly, but cool again when the hot water is turned back on.

The diverter valve has an over-ride lever on it, but it is loose and floppy, and does not seem to do anything.

It is a Potterton 60e boiler and a Honeywell F5 9824 valve (I am not sure whether this is a 2 or 3 way valve).

Does this sound like a defective valve?

Thank you.

James.

 

[MANDATE]

A 3port valve has 3 pipes (1 in 2 out) a 2port has 2pipes (1 in 1 out)

Sounds like a balancing problem. With both HW and CH on too much flow through HW and not enough through CH. With just CH there is no flow through HW.
Options are
(a) open all the radiator lockshield valves just a touch more.
(b) fit valve on HW circuit to restrict flow

 

[Agile]

If there is no balancing valve on the cylinder heating coil then thats most likely to be the problem as described above.

But that would mean that if CH only is selected then the rads would heat up properly.

If that is the problem then a 22 mm gate valve on the cylinder coil set to give a differential of 10 C with the cylinder cold and then remove the red valve top!

Tony

 

[Catceefer]

Would a pump that is not powerful enough cause the same symptoms? The problem only started when I fitted the new pump after the old one failed. The new one is not the same as the old one.

Out of interest, is the head of the pump the height from the pump to the highest point or the vertical distance from the lowest point of the system to the highest point of it?

Thank you.

James.

 

[Agile]

Most unlikely! Should be on setting "2".

But much more likely that the pump valves are not fully open inside.

Could also be dirt in the eye of the pump!

Its a circulator and not a pump and the head is irrelevant to you, on ly to the system designer.

I assume you are in a standard house and not a mansion!

Tony

 

[ianblue]

You say this problem only occured when the pump was changed, So obviously the that's the thing to look at first.
As agile said "it should be on setting 2"
What he is saying is the pump would normally have different speed settings sometimes two or three. I would try that first depending on type there would be a switch on the side.
It does seem unlikely that you would have to start balancing if the system worked perfectly well before.
I've never come across that particular Honeywell valve. Are there any other numbers on it? Usually starting with a V.
If I knew the valve I could tell you how to check it.

 

[MANDATE]

It does seem unlikely that you would have to start balancing if the system worked perfectly well before.

But the pump has been changed and there is not the same force as previously.
When CH only is in operation the resistance in the circuit is at its highest and the new pump can cope with it. When the HW circuit is open there is now a easier route and the water will take that route rather than the more difficult route through the radiators. So lowering the CH circuit resistance or increasing the HW circuit resistance will resolve it.
Regarding the pump, increasing the speed might help a little but there's very little force to start with.( just enough for circulating)

 

[ianblue]

[/quote]
But the pump has been changed and there is not the same force as previously.


Exactly thats why the speed should be checked.

James can you tell me the pump reference.

 

[Catceefer]

Thank you all for your replies and the clarification about head.

Zone valve: I regret that I can find no other numbers on it. I did a search on the web, but could not find anything useful there on it either.

Pump setting. I have tried all three speed settings, but with no discernible change.

Pump type. It is a Flomasta 7000233 pump from Screwfix.

House size. Regrettably, not a mansion, just a normal 3 bed semi.

Reading the replies again and thinking back to when I fitted the pump, I recall that I closed the valve on feed into the heating coil for the hot water and opened it fully when I finished. I have now closed it down to just off shut to see what that does.

 

[ianblue]

Well James looks like you've solved it.
I thought you had only changed the pump. If you had said you had moved the setting on the HW balancing valve we would all have known straightaway what the problem was.
Anyway glad you have got sorted. Now you can look forward to a nice warm Christmas.

Cheers Ian

 

[Catceefer]

"If you had said you had moved the setting on the HW balancing valve"

To be honest, I had completly forgotten until I read the comments on here about balancing the two systems.

Again, thank you all for your suggestions. I have just come back in from outside and it is like toast in here.

Regards,

James

 

[Catceefer]

Bother. I spoke to soon.

Starting from fresh this morning with the valve into the heating coil almost shut, the radiators downstairs were tepid and those upstairs only marginally warmer. I turned off the hot water and all all of the radiators heated up quickly and remained hot when I turned the water back on.

I am reluctant to shut the flow to the coil much more as I am concerned that I will simply end up with no hot water.

I will have another look at the check valves in the downstairs radiators to see whether they need opening a bit more, but other than that, I am stuck.

Would I do well to drain everything, check the pump for anything obvious like a blockage and try again? The valves to the pump do not shut off properly, so I cannot just close them to check.

Regards,

James.

 

[ianblue]

I wouldn't go draining down just yet. There could be a problem with the motorised valve. Is it three way, possibly a Honeywell v4073?
The thing we must keep in mind everything was ok untill you changed the circulating pump. Or was it?
I am sorry I have to go.... take her indoors to the shops.
If no-one else comes to your aid I will be back later to see how you are doing.

Cheers Ian

 

[Catceefer]

Ian,

Thank you for your reply.

The problem all started last winter when I replaced the pump. It was definitely faulty as it was making an awful grinding noise and the heating was inefficient. However, it may also have been masking a fault elsewhere in the system.

It is a three-way valve with a feed in the middle and two outlets. THe only numbers that I can find on it are Honeywell F5 9824 on the tin housing and 40003279-002 on the inside of the lid. It also says "sundial Y plan 3 position diverter valve".

I have tried different combinations of the room stat and the stat strapped to the front of the hot water tank to see what effect it has on the apparent position of the valve and the lever on the outside. The results are:

Room stat max - tank stat max - valve lever loose
Room stat max - tank stat min - valve lever loose
Room stat min - tank stat max - valve lever mid-way in slot on case
Room stat min - tank stat min - valve lever mid-way in slot on case

I am not sure what these indicate, if anything, but I would welcome any suggestions.

Finally, what does "manual" mean on the valve and what effect does putting the lever in this position have?

 

[ianblue]

You have the Honeywell sundial system which utilises the V4073 honeywell valve.
Your pump was making grinding noises and reduced performance, the classic signs of a worn out pump.
You have done the right thing in changing it.
The lever is a manual lever and can be latched towards the heating position. It is not a true indication of the valve position.
Not sure it is worth checking wiring at this stage since everything has been working before. I take it you have not changed any wires?
With both HTG and HW on at the controller turn cylinder stat to minimum and room stat to max. The valve should close port B and open port A.
Turn cylinder stat to max. Valve should run to mid position.
Turn room stat to min. Valve should return ,pulled by spring to port A.
If this all works out there could well be a restriction in the main flow. Since if there is a reduced flow just sufficient to circulate around the heating circuit but when shared with the cylinder most of the flow will go to the cylinder starving the Heating.