Honeywell 42005748 001 Wiring Centre, 24 V

Gets 4 stars because I have used this wiring centre before without any issues how ever having purchased another one to install at my partners house along with a brand new nest thermostat the system threw up faults and after eliminating the nest it tuned out to be two terminals on the clock input terminal block of the wiring centre shorted to each other, when selecting heating on the water came on as well. Solved it by removing the heating on trigger wire from the nest and white wire from the motorised valve and fitting a separate terminal to join them back up which cleared the fault. Could have probably cleared the short on the back of the PCB but it is not removable from the housing. Overall it’s a great simple to install wiring centre that makes everything neat and tidy, it was just a one off faulty wiring centre that for a short period turned my hair grey. It fully deserves 5 stars so don’t be put off by my 4. Y plan system (cut links 4 and 5 (pump over run from boiler (cut link 6))).

Bought this to replace an old programmer which had an integral wiring centre since I wanted to install Hive. My system is a simple Y-Plan and this wiring centre made it a breeze to switch over the components. Everything is clearly marked, including colour coding where necessary. Great product. Made my switch over incredibly simple even for a DIY-er. Hive connected simply to the new wiring centre and worked perfectly. Saved myself a fortune in professional costs.

Excellent product. Makes the medusa head conplexities of HW and CH home wiring for a DIYer so much easier. I would encourage buyers to fully read the back cover very carefully (as I did not until the third attempt) - its not particularly well written, but all the information is there.

Not really a review as this item was ordered, but was not suitable for a twin pumped system.