Hi,
Remember that Google does things very often that may affect you unintentionally for no apparent reason, because of algorithm changes and glitches or attempts to catch spam. The ways of Google are beyond human understanding. The eruption of the volcano is not always due to human sin and cannot be avoided by sacrificing young girls or whatever.

Disappeared where? Search results of this type are localized. Make sure Google knows the firm is in the UK if that is what you want (you can tell them at Webmaster central).

Sandbox would not occur after your site was already listed and had PR. You have PR 3 and are therefore not in any sandbox. Yes, there is still a sandbox, IMO, though it may not be called that.

Penalty MIGHT occur but is less frequent probably than frantic Web site owners might think.

For Google algorithm change check if the number of sites listed for a keyword search has gone DOWN - usually indicates Google has done something that affects that keyword.

Advice - take ICS out of the <Title> - Heat Pump or Heat Pumps is what you are interested in, no?

Make sure each and every page links back to the main page with the keywords in the anchor text. I didn't see that. "Home" is not your keyword, so why use it as anchor text? SE Spiders are very dumb and mechanical.

Add more text to the main page that explains about heat pumps - maybe 1000 or more words if possible, and increase the ratio of text to code - and change the text from the duplicates so main page at least is different again. You have 3 little boxes with the same text - not the best idea I would think "Discover the benefits of ICS Heat Pumps in your home."

Never have link text (anchor text) that says "more" - this sounds idiotic, but Google decides that "more" is a keyword on your page. I saw it in Webmaster central results. No kidding. Link the title of the page. Remember - search engines use anchor text to determine the content of the linked page. Don't use "more" unless you want to be #1 for keyword "more"

All your ALT image tags should have the keywords if possible.

Add 1-2 blogs with links to your pages.

You have 62 pages registered in Google. Make sure that all your pages are registered. generally, a 62 page site is not going to get top billing for reasonably popular keywords. If you did do so for a while, it may have been extraordinary.

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