We've got the Alde 3200 in our MH, it works very well on both electric and gas.
You haven't said where you're located, when we needed some work doing on our previous MH which also had the same system I just googled Alde Heating Servicing Hampshire and found a guy locally.
https://caravaninfo.dk/alde-3000-3010-fejlfinding-gode-tips/?lang=en - this is a Danish website so the English isn’t perfect, but it has a troubleshooting section which may help.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets