Central Heating

[MartY_sp]

HI guy's .

Need a bit of Advice/Help ..

Last night my partner heard a very strange buzzing whiring noise coming from what i now know is the "mid position actuator" .
Now before looking or knowing what this was my partner thought she had knocked maybe a lever that is on the side of the unit (little black plastic lever) with the markings "W---M---H" So i thought i thought i'd try moving this lever to another setting it was currently on W so i moved it down with a little force and it made a forceable click and dropped to the H (thinking to myself it gave resistance and maybe i shouldnt have done that ) .
Anyhow we left it over night the buzzing had stopped but this morning we have found we have no hot water or heating (knew i done something wrong and should have looked it up before touching ) .
Now from diving into the net and ready up on thing's here and other site's . i have found the pump is very hot and think this is probably due to what i have done to the actuator (probably now not working ) .
I have looked up the model and found it to be a "drayton mid position actuator MA1" and wanted to know what i need to do to replace it .
Could i isolate the power from main's get a new actuator removing old one replacing the wiring one by one with new unit , Have read that the old unit remove's by clicking a button and it detaches from pipe's but do i need to drain the system first ? as was going to leave the old base and pipes and just replace the plastic unit .
Hope you understand what i have written and look forward to a quick reply if possible .

Btw how would i know wich size it is as i have found a 22 and 28m on sites but nothing on unit that i can see tell's me wich it is ?

 

[Bahco]

Move the lever to mid position to allow both heating and DHW

 

[MartY_sp]

thanks for quick reply .. but i did forget to mention that lever has now dissapeared into the box itself .

 

[MartY_sp]

lets try make this a bit simpler loads of looks no reply's ...

If i was to remove the mid position actator MA1 "pressing the clip to release it " from it's pipe work , Can i do this just by isolating the power or do i need to shut of the water supply that passes it ?

Due to the lever i think braking as it now has gone within the unit i was thinking of replacing this piece as it was making funny noises before hand , thus maybe it was on it's last leg's anyhow .

 

[JohnD]

The motorised valve comes in two parts. There is usually a box containing the electrical parts, as a head, to the brass valve part.

You may be able to get a new head to put on, wihich does not involve draining and plumbing. If you can see the brand and any other markings, or take a photo, someone will probably be abe to identify it.

Otherwise you can replace the whole thing.

 

[nickso]

the head can be repalced without draining down.

most likely the spring bar inside has snapped off or the motor is shagged.

on the other side of the bit that says w-m-h you should see the clip that removes the head. push in and lift off. if you dont have a clip you may need to change entire head if the internals are broken beyond repair. you can get spare motors no problem.

i think the head you need is drayton part number 27651, its listed as a MA1 head here:

http://www.invensyscontrolseurope.c...A3-32C983351874/0/D42_4DraytonMotorValves.pdf

 

[MartY_sp]

Thanks for your responses guys great help .

The first one in the picture of that link nickso is exactly the same as the one i have mate . so im looking for that part number m8 ? 27651
Have located the clip on other side of unit and just testing it found it does losen

 

[gas4you]

you may need to check your pump as well as this should not be red hot to touch.

 

[MartY_sp]

found the pump gets hot when a programme i,e hot water or central heating is selected . if none is selected in the programe box then the pump stays cold .. although when selected the pump gets hot after a while but no heat is being put through any of the rad's and no hot water . Was thinking (but correct me if im wrong ) that maybe due to the actuator not working the hot water is building up at the pump but if nothing is selected the pump isnt drawing on the hot water ? .. (i ama noob so forgive me if i am wrong )

 

[JohnD]

when a pump gets very hot it is generally because it is jammed (so no water travelling through it). If you have a problem with the 3-way valve that might be connected with it; but I can't see why, unless it had closed all the ways. Usually they have 3 positions: Hot Water; Mid (=both); Heating. No "off" position.

You should find a largish screw in the centre of the pump, with the rotor spindle behind it. You can take this screw out (not much water will come out as there is a seal) and see if the rotor is spinning when power is applied to it; or if (with power off) you can turn it with a screwdriver. Not spinningmeans jamed. Spinning but not pumping can be other problems.

Is there plenty of water in the system? If you bleed a radiator, does water squirt out? Is the water black?

I hope you have an immersion heater so you can provide hot water for daily life while it gets sorted out (life must be terrible for Combi owners

 

[MartY_sp]

thanks ..

Closer inspection of pump :
Removed the large silver screw on front no water squirted or dripped out .. the inside of screw is a chalkey black nothing was spinning inside either when trying running a programme or not but the pump did get hot again when programme switched on .. here's a couple of snaps i took on my phone thats inside . and heres the screw with the chalky black residue
The pump is a grundfos Electrica .
I opened the rad bleed's (we have four rads .. 1 living room , 1 dining room , 1 Hallway and 1 in bathroom .) and the 3 down stair's are all full and clean water passes through .. But the bathroom rad when i bled it just let air out so i continued to wait opening the valve more and air passed more quickly , it ended that i fully opened the valve and no water has come through just air :s . Now the air has stopped and still i can remove the valve so it's fully open and nothing comes out .
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[JohnD]

"Now the air has stopped and still i can remove the valve so it's fully open and nothing comes out"

Bad news. This suggests that the water supply to the system has failed. Most likely (assuming you have a Feed & Expansion tank in the loft) either the F&E is empty (e.g. ball valve stuck) or there is a blockage in the feed pipe (this is almost invariably where the 15mm feed pipe comes down and joins onto the main circulating pipe, usually close to the pump). If you can lay your hands on a strong magnet we can describe how to identify the blockage, which is almost certainly of black sediment that ha settled and hardened into a plug. The downstairs rads will have had more pressure but the upper part of the system may be partially empt.

If you can provide a photo of the pipework round the cylinder and pump, we can probably point out what to do.

The pump is probably jammed and you will probably need a new one. It may have been caused by sediment and/or running dry due to lack of water.

Do you feel up to replacing it yourself? If the system is only a few years old it may not be too hard (on an older system the valves are more likely to be jammed). Otherwise, ask around friends and neighbours for a recommended plumber or heating engineer.

You will also need to deal with cleaning the system and refilling with inhibitor, but we can deal with that separately.

If you have an immersion heater you can carry on using that until you get it fixed. But you must turn turn off the boiler.

 

[MartY_sp]

thanks john .

This really could'nt have happened at a more wrong time than now :s . So really would like to try and do if possible myself and keep as inexpensive as possible (but would'nt we all) .
About 6 years ago i replumbed my kitchen to put a new kitchen in and for new appliance's washing machine and dishwasher plus new sink unit due to old council stuff and we had just bought our first home . Was told by a plumber it was a great job . Better than the bathroom that was actually done by a plumber or cowboy that was done at the same time (was looking to tackle that in a couple of month's as we are moving through the house decorating , and the bathroom has had nothing but problems with leak's etc since done ) .
The piping i believe is younger than 10 yrs old due to having central heating put in when we were council tennants but cant remember exactly when this was done sorry . I did enjoy doing the kitchen and started finding an interest in plumbing so if i can do the job i'm not afraid to try if it's possible .
i have taken pictures of piping and the tank's they will follow just sorting them out now to post .

Right also just to say a day or so before this problem i did have the dining room radiator disconnected for decorating and respaying of the rad . So maybe i'm thinking when reconnecting this may have caused the blockage that you talk of ?

 

[MartY_sp]

ok heres the setup :







There are to tanks in the loft this is the smaller one :



This is the larger :


the large tank has clear water in but scale over the ball and fillerment . also some lying in the bottom of the tank

 

[JohnD]

Taking the radiator off will not have caused the problem (blockage in feed) but it will have made it visible - when you put the rad back and it filled up with water from the system, it will have lowered the water level in the rest of the pipes becasue there was no top-up from the F&E tank.

This is very common.