Nickfromwales

Just hoover it is there’s been some time for dust / shite to settle, and butter the floor in all directions before sticking the tile down. You’ll see the adhesive doesn’t quite want to stick at first, but then it will as you work it in. Put effort into this, and tell Aunt Fanny I said hi 👋.

No need for primer mate. 👍

Get cracking before someone else grabs it. Also, make an offer of £55 first

If DeWalt… https://www.ebay.co.uk/itm/156176452021?itmmeta=01HW03AAJKA4SQK45Y5RY3M6Y5&hash=item245cd789b5:g:oQAAAOSw4NRmJOds&itmprp=enc%3AAQAJAAAA8F2%2FvAmv0a6y1j6oH%2FHZ5IW034bLCVEwmrED5QrrCrDodOCvu79j20m%2BM0RUNC60NHKOGHH6azqYN2fqWOjx1OhwA3vh8RKpjSMvXie4AN3QXYaaxH7e9lKltlo0fcmXGG08YRbSHsUZi%2BCC1SXq24sKdzBqZLtJNnJKBU8Y%2FH6eYV13F82EyfcyPZpj9VrL5OBMIPkWIqunX4ir7RnOy3laNbL%2FtisLojE0XmQtI4ZtvkET08t50biU9ygIAJwh1rttJwHt9FxlL5X6fUvhUXeATfOghCEdrApbIWxJfTC3dj80vXFuOAr3iyd%2BFJH4Rg%3D%3D|tkp%3ABk9SR8apqYPgYw

Go for a naked tool that is compatible with the batteries and charger you already have? I bought a used Makita off eBay and it’s had an absolute beating over the last 5 years. Still going strong, just a bit noisier as it’s not as ‘tight’ due to wear & tear, but with what I’ve done to it I’d be happy to buy one once every 12-18 months as it’s earned its money hundreds of times over.

Could be the pump on the way out, or a pipe which has become blocked over time.

1,000,000%, defo use tile adhesive.

What size gap do you think you'll need to fill? If the substrate is very robust and flat / level then a tube adhesive will suffice, prob cost sub £40 in CT1 to do this if it's a 900x900mm tray with a 6mm gap (undulation) to bridge. Is it a GRP or stone resin tray, or one made from the Wedi-like insulation material?

MBC install UFH in their passive rafts as standard, they'll even work with a design from your ASHP company but MBC will defo be fine without guidance. Look at your contract and you'll see it in there as an assumed 'optional extra' in the price.

Yup

Sherlock would blame the cleaner. Facts speak for themselves.

Mondays and human intervention is the culprit, obvs, unless the 'Ghost Of Monday' is resident at yours

The pex-al stuff is crazy hardy tbf, and most UFH installs I do on heated constructional slabs have either us or follow-on trades walking on them, sometimes for days, without any detriment. Damage to this type of pipe has to be near malicious for this to leak.

There is a significant saving via the HR element