Problems with Economy 7 Hot water boiler

[alisoneadie]

I moved house a couple of months back and have been having issues with the hot water. When we first turn on the taps / shower in the morning the water heats up, then goes cold about a minute later. If we leave it running then most times it will heat up again about a minute later and it is then fine for the rest of the day. Sometimes however it just stays cold even if we leave it running for ages. If we switch it off and wait 10 minutes or so then we can normally get it to work ok again.

We got a plumber out and he said it was a problem with our pump. He replaced this, and replaced the thermostat valve at the same time, in case that was part of it. In doing this he had to drain the system as the isolator valve had got all limescaled up (as had the old pump).

We then had to get an electrician round to wire up the new pump, and he said there was also a problem with our timer / boost unit, so he has bypassed this to give us hot water until it can be replaced. The problem is we still don't have hot water.

The tank itself feels hot and the pipes at the top are boiling, but we're not getting any hot water out the taps. There isn't even any hot water reaching the thermostat valve - the pipes on both sides are stone cold. The plumber has been out again this morning, but he says he can't see anything wrong with it and thinks it must be to do with the wiring. The electrician is coming back later today.

However, I'm beginning to lose faith in their knowledge (especially as they keep telling me different things) and was wondering if anyone on here has any idea what hte problem might be? Or failing that, can anyone point me in the direction of a nice diagram giving the schematics of an electric boiler so that I can at least know what each part does and how it all fits together?

Just went to check it again before posting this and the pipe going into the thermostat valve is now hot at the top, but still cold at the bottom - could there be an airlock in there from when he drained the system? If so, is there any way I can fix that?

 

[Agile]

We have absolutely no idea of what make or model of equipment you have.

If you have little faith in your plumber ( nor do I if he cannot even wire up a pump ) then why not ask for the manufacturer's service agent?

Tony

 

[gas4you]

What exactly is it? What do you mean by 'Economy 7 ' boiler?

An actual electric boiler on a standard heating system, or a hot water cylinder heated by immersion heaters?

Your post, without further information, is highly confusing I'm afraid

 

[alisoneadie]

Apologies - the timer unit is Horstmann, but doesn't specify a model number. The cover over the bottom of the tank itself is Everest Heat Bank, HBPP-150-A.

Our house has electric heaters - the tank is just for hot water. It is a hot water tank which uses cheap 'economy 7' electricity to heat up overnight. (though has the option of a boost using standard rate electricity during the day).

On the plus side, I've now got hot water coming through my taps, so I think it probably was an airlock. I'd still be interested in that boiler schematic though if anybody knows where one exists?