Plumbing and Heating

bodyguard1

Need some advice please changed the hot water tank recently and now we have no hot water in the taps or the radiators, reckon the pipes are air locked any tips as to how to clear the airlock in the pipes ?

jd80

Clarify.

Are you actually getting water out of the hot tap - whether it is hot or not?

bodyguard1

Sorry yes we are getting water out of the taps but it is not hot and we can here a gurgling sound in the pipes at the side of the fire which would suggest an air lock

jd80

I take it when you say 'tank' you mean the hot water cylinder?

Is it a single or dual coil?

bodyguard1

Yes its a dual coil hot water cylinder

jd80

I take it the cylinder is cold to the touch?

I take it from your posts you are heating the cylinder with solid fuel via one of the coils.

Is that correct?

bodyguard1

Yes both the cylinder and the pipes leading into it, rads are luke warm

jd80

are you heating one of the coils via solid fuel at the moment?

bodyguard1

Sorry I persume so a plumber changed out the cylinder and when the problems arose he said he didn't know what the problem was so I had to get another plumber to look at it and he said it was airlocked but has to return on Monday to sort it out but if there is a simple solution to the problem I will try to clear it myself

jd80

right now at this moment in time how are you trying to heat the water?

bodyguard1

The only way to heat the water is to turn on the immersion.

jd80

You are not making sense.

In a previous post you mentioned 'fire'

Are you tring to heat the water with a solid fuel cooker or stove?

bodyguard1

We have an open fire with a back boiler which normally heats both the radiators and the water in the hot water cylinder upstairs however since the airlock the only way to heat the water is via the emersion switch

jd80

ok

What source of heating do you use to heat the second coil in the cylinder?

jd80

I am trying to ascertain if you can get hot water and rads with that second source of heat

bodyguard1

you've got me there as you might have guessed from my replies I am not technically minded when it comes to plumbing and the workings of a twin coil cylinder

jd80

Well do you have an oil boiler or a range that also heats the water?

Are you actually sure you have a twin coil cylinder?

bodyguard1

Yes we also have oil fired central heating which will heat both the water and the heating seperately but that defeats the purpose of having the open fire with back boiler which is currently not doing its job. Yes it is a twin coil cylinder as that is what was purchased and the second plumber confirmed same

jd80

I understand.

I asked in order to ascertain if you obtain hot water and rads with the oil, which I assume you are

bodyguard1

Yes, we can obtain hot water and heat the radiators using the oil but with the cost of oil nowadays I would much prefer to heat them via the back boiler

K.Flyer

The part that intrigues me is that the first "Plumber"(?) has left you to fend for yourself and having to get a second Plumber to sort it out, very poor service.

jd80

HARD to diagnose remotely and not knowing what various people have done - but:

You are getting water from the hot tap albeit cold/luke warm when the sole source is the back boiler

The rads are luke warm from the same source

Everything works with the oil

You note gurgling in the back boiler



Being a solid fuel source heating the cylinder, you should have a gravity system from the back boiler to the cylinder.

The pipes should gradually rise on the flow out of the back boiler to the coil to allow the hot water to naturally rise - at the highest point it should have an expansion vent (usu pipe into loft) for safety . Also for safety there should be no valves on the flow to the coil from the back boiler

On the return (coil to back boiler) there should be a fall in the pipework

There also should not be a valve on the return - but check in case there is and it is closed

It could be that the pipes are not following a rise/fall after the recent installation

However, the rads are also lukewarm

That could it be that the pump is not on

*BUT* I am thinking (more worrying) there is not enough water in the back boiler

OR you do not have a vent pipe on the flow to the coil (maybe they put on an expansion vessel or there is some other strange concoction/set up on your system ) and maybe the air cannot get out.

Really, to be safe, you should extinguish the fire in the back boiler until you get this checked out by a decent plumber.

Whereabouts are you in the country (PM if necessary)

bodyguard1

The pipes should gradually rise on the flow out of the back boiler to the coil to allow the hot water to naturally rise - at the highest point it should have an expansion vent (usu pipe into loft) for safety . Also for safety there should be no valves on the flow to the coil from the back boiler

It could be that the pipes are not following a rise after the recent installation

You are correct in your conclusion, the second plumber reckons that as the new cylinder which is larger than the one which was replace the connections on the side of the cylinder were in a different position and therefor the guy fitting it had placed them at an angle going into the side of the cylinder thus causing the pipes not to follow the rise correctly.

\he said that if the airlock doesn't clear itself he will have to drain the cylinder on Monday and check the angle at which the pipes enter the cylinder

jd80

Really for safety, given that it a solid fuel system with a possible airlock between heat source and vent, you should let the fire burn out and not light it again until these problems are rectified by a competent tradesman

It does not fully explain why the rads are lukewarm though - pump off, valve shut from the back boiler to rad circuit, water low?

However, rads heat with oil since new installation (thus not water low) don't they or do they?

Did you actually run the system via the oil boiler since the works were completed?

Sleeper12

K.Flyer wrote: »

The part that intrigues me is that the first "Plumber"(?) has left you to fend for yourself and having to get a second Plumber to sort it out, very poor service.

I know this thread is a year old & I'm sure this guy got his back boiler sorted but I wanted to bring your attention to the comment above.

Please when getting a tradesman ask to see their insurance. Don't always go for the cheapest, this can cost you dearly. Don't assume that because they have badges like RGI that they are qualified to do the job (though there are some very good RGI). The best way to get a tradesman is word of mouth. A recommendation from someone that has used them goes a long way.

Most importantly THEY SHOULD BE INSURED. This is for your protection.