Vokera boiler problem - varying pressure

[Aldrich]

Hi

I have a problem with a Vokera Mynute 20SE boiler (which is not a combi-boiler). In the early morning, when the heating / hot water comes on, a steady drip of water comes out of the bottom of the boiler, and some water comes out of an 'overflow (?)' pipe to the outside. Consequently, the system pressure drops. When the system cools, the pressure is then 3 bar, giving the drip.

The instruction manual requiries a pressure of 1.5 bar, but is that the cold or hot pressure? Or should they be about the same?

Please can anyone comment on this?

Thanks

David

[Lurch]

On Tue, 22 Feb 2005 08:14:50 -0000, "Aldrich" strung together this:

Off the top of my head, and there are people who know more than me about this, 1.5 bar cold pressure is what it should be set at. The PRV usually opens at 3.5 bar. If it's going above that every day then something is not right in your system, either the water is not flowing correctly or there is a pressure vessel with a split diaphragm. Has it always done this or is it a new thing? What's the type and state of the system it's connected to?

[Jim Alexander]

The main symptoms describe an expansion vessel which has lost its expansion volume over time. Quite common after a few years service unfortunately. May be shot but can't say. The FAQ explains how to recharge the expansion vessel which may work for a year or two. You should investigate and cure the drip which is a second fault. Possibly the discharge pipework is leaking internally.

Jim A

Important you recharge the expansion vessel according to the FAQ. Then fill cold. If the expansion vessel is working properly the pressure won't vary greatly.

Jim A

[Aldrich]

Hi Jim and Lurch

Thanks very much for your answers, they were very helpful. In answer to your questions, I noticed the problem only a month or so back. My system is sealed and serves heating, and hot water via an immersion tank.

Recharging an expansion vessel, or replacing a PRF, are really beyond my capabilities. If anyone can recommend a Corgi registered Vokera engineer in North East Surrey, I would be grateful.

Given that the repair could cost several hundreds of pounds. Is there any kind of maintenance contract that I could enter now, that would cover the repair?

Thanks again

David

[Jim Alexander]

Wouldn't expect everybody to be confident replacing a PRF but recharging an expansion vessel is an entirely non-invasive process that possibly you might manage. Read the FAQ. Not a difficult job for any heating engineer, easily done in an hour. Quite likely that will keep things going for a year. If its totally shot, possible but unlikely, you'd have a bill for that as well which is why its well worth thinking about recharging it DIY. The spare part costs about £60 online. There is also a temporary emergency workaround explained in the FAQ.

No, because insurance never covers pre-existing conditions but once its working again only you can decide if you want to pay £15/month for peace of mind and the offer of expensive powerflushing.

Jim A