Only one working radiator

[CHRI1111]

Hello all,

I was hoping someone could help me solve and repair my central heating issue.

Only a single radiator works in the property in the bathroom.

This room is located directly above the boiler on the first floor. The boiler is located within the kitchen on the ground floor.

I notice when the boiler fires up the pump says 1 watt, then a few seconds later has two dashes.

All the other radiators are stone dead cold.

Any ideas?

 

[CHRI1111]

Correction-
A second radiator in the adjacent bedroom is warming up, to include its outlet pipe.

The third radiator in the second bedroom is cold, but notice the inlet pipe is luke warm. The central heating system has now been on for 30 minutes.

When I tested the system in Winter 2016 only one radiator got hot, so a little improvement since then for some reason.

Chris.

 

[ShaunCorbs]

Take the trv heads off and does the pin push down ? Also lift it till it stops don't force it up too much you should have heating

 

[JCplumb]

The only reference I can find to the 2 dashes shown in your pic is here:
http://us.grundfos.com/content/dam/GPU/Literature/ALPHA2/99187617_0217_ALPHA2_IO_Internet.pdf
It seems to be an indication that the supply voltage is too low.
Whether that's normal when there is no call for the pump to run I don't know. Hopefully someone else on here has more experience with this particular pump.
The fact that only one rad upstairs above the boiler is getting hot indicates a pump problem most of the time. Your boiler may also lock out during calls for heating because the hot water isn't dispersing quickly enough.
Doesn't look like you have access to check the return pipe temp while it's running.
I'd say most people would need to call a heating engineer in this situation.

 

[CHRI1111]

My boiler does keep cutting out, so I suspect the pump is either jammed or faulty?

 

[ShaunCorbs]

Try this

Press and keep pressing the grey arrow point so it fills the II mark

 

[CHRI1111]

This is the trv. Does push down.

 

[CHRI1111]

I've pressed the arrow some 40 times but nothing has changed on the display

 

[CHRI1111]

I've also put my hand on the pump and cannot feel it vibrating.

 

[ShaunCorbs]

I've pressed the arrow some 40 times but nothing has changed on the display

While it's on / got power?

 

[CHRI1111]

Yes

 

[ShaunCorbs]

This is the trv. Does push down.

View attachment 30631

Are the other trvs like this one easy to push down and up ?

 

[ShaunCorbs]

Yes

I would say new pump then sorry to say

Should adjust

 

[CHRI1111]

The other upstairs radiators don't have trv's - got these:

Not sure how to check these?

 

[ShaunCorbs]

That's fine there lockshield valves won't go wrong unless there shut (anti clockwise to open if your wondering) but if they've worked before leave them point to either controller not giving power to the pump or duff pump

Do you have a multi meter?

 

[steadyon]

Could be the bathroom radiator is on the hot water primary circuit with either central heating not called for or a duff motorised valve.

 

[CHRI1111]

I've never turned those off and the system used to work fine.

I don't have a multimeter unfortunately, would that be to check the power to the pump? I am wondering whether I can try and turn the pump manually to see if it's siezed but don't see a screw on the front to get access?

 

[ShaunCorbs]

I've never turned those off and the system used to work fine.

I don't have a multimeter unfortunately, would that be to check the power to the pump? I am wondering whether I can try and turn the pump manually to see if it's siezed but don't see a screw on the front to get access?

That's fine

And yes to eliminate the programmer any chance of another pic close to the bottom of the cylinder/ can you see a port valve

Like in the pics below?

 

[CHRI1111]

As in this thing?

 

[ShaunCorbs]

Yes can you hear that moving (should click and pump turn on)

 

[CHRI1111]

I think so. Very faint but there is a single click. Tried to upload sound file but won't let me.

 

[ShaunCorbs]

That's it, I would say pump but without checking the voltage to the pump can't be 1000% sure

 

[CHRI1111]

Is it worth checking whether the pump is seized?

 

[ShaunCorbs]

Is it worth checking whether the pump is seized?

The only way with the erp series is to take the pump out completely, there's not a manual air vent like the old series used to have

 

[CHRI1111]

Ah that's a shame. Oh well if im.takibg the thing off I may as well replace it! I've found a you tube video explaining how to replace, but I'm guessing I'l need to drain the system down as I can't find the isolation valves to the pump itself.

 

[ShaunCorbs]

Yes and replace the pump valves as there the type to leak if touched

 

[CHRI1111]

Thanks for your help.

 

[Sparkgap]

That's it, I would say pump but without checking the voltage to the pump can't be 1000% sure

Can I suggest before ripping it out disconnect the pump supply and put it on a plug and extension lead to try it. it wouldn't be the first time I've found dodgy switch contacts meaning the pump isn't getting voltage.

 

[CHRI1111]

I may get someone to do it for me as there seems to be a lot involved. Can't find a drain valve now. Any ideas of what I should expect to pay for this?

 

[ShaunCorbs]

Can I suggest before ripping it out disconnect the pump supply and put it on a plug and extension lead to try it. it wouldn't be the first time I've found dodgy switch contacts meaning the pump isn't getting voltage.

But then the display wouldn't light up ?

And op your best having a few plumbers quote

 

[Sparkgap]

But then the display wouldn't light up ?

And op your best having a few plumbers quote

Basic version: dodgy contacts can cause high resistance. When the pump is off load the voltage is high enough to run the display. When the pump load increases the resistance causes the voltage to drop. LED displays don't need much to run but motors do, hence the 'fault'.

 

[heliotrope]

Has no one noticed that the pump valves appear to be in the
closed position?

 

[CHRI1111]

Where are the pump valves? I can't see any.

 

[ShaunCorbs]

Has no one noticed that the pump valves appear to be in the
closed position?

They look open to me

 

[ShaunCorbs]

Where are the pump valves? I can't see any.

Below the pump brass connectors the raised notch

 

[JCplumb]

Thems the buggers

 

[CHRI1111]

I see. They look open to me. Plus I've never closed them.

 

[Dkdc71]

Did you check and make sure the system has enough water in it before you rip anything out or a fill valve needs to be turned on system might be just going dry not enough water in it and the boiler will keep going to lock out

 

[Dkdc71]

Just call your local plumber in I,d say it just needs to be filled and tested maybe a bit of balancing to be done nothing major get to have a look at the old leak on the trv pipework as well I recommend

 

[doitmyself]

Whoever wired the pump didn't do a very good job. Might be worth unplugging and checking the connections are tight.

What speed is the pump on? If it's on Autoadapt, try each of the fixed speeds in turn to see what effect it has.

 

[CHRI1111]

How do o check what speed the pump is on?

 

[doitmyself]

This pic shows it's on Autoadapt.

Page 12 of the attached pdf (below pic) tells you how to change the speed setting. It also explains what the "--" lights mean.

 

[Dkdc71]

Zoom in they are open