A bit of an unusual topic, as these are very rare in the UK.
I went back to Poland to commission, test and tune the 20kW solid fuel boiler and the domestic heat exchanger for the hot water tank (300litres). Old heating system with steel 2-inch pipes and cast iron segmented rads
We were warned, that the boiler can struggle a little to heat 210m2 (most likely 24kW would be better for 5 bedrooms, lounge, kitchen, bathroom and the toilet).
On arrival - the house was very cold, an elderly mother is afraid of lighting fire.. (oops, a huge design fault). 12 deg inside, 300litres DHWT @mains cold.
There is an automatic coal delivery: every 1min 40 sec, spiral turns for 8 seconds, air pump set up to 15 (in scale 0-30).
I decided to torture (aka stress test) the system and kill some legionella bugs. Target: 75 Cels on rads and 75 inside DHWT (temporarily - I will reduce it appropriately), so after some tweaks, delivery 9 seconds, every 1:20min, air pump 15
Few questions though.
1. Ashes are approx 10% of the burnt coal volume. Barely any slag present. Good/bad?
2. I do not understand what is the purpose of the valve pictured. It has to be there as per manufacturer's blueprint, but what for? Is there a problem when cold water gets inside the boiler, hence the bypass, to slowly seep the warmth into the CH system?
3. System struggles to get to my desired deperatures (75 and 75). looks like 55CH/65DHW. Should I give it more air and fuel? Wait until the bulding warms up a bit more and then to tune the settings?
House got warmish in about 6 hours (16 cels), currently holds 19 degrees in all rooms, Tap hot at 65 after 24h. Used 25kg of coal.
I do get that this technology is widely frowned upon, but for less than £10 per day, it is quite tricky to heat the big house.
Any advice would be appreciated.
I went back to Poland to commission, test and tune the 20kW solid fuel boiler and the domestic heat exchanger for the hot water tank (300litres). Old heating system with steel 2-inch pipes and cast iron segmented rads
We were warned, that the boiler can struggle a little to heat 210m2 (most likely 24kW would be better for 5 bedrooms, lounge, kitchen, bathroom and the toilet).
On arrival - the house was very cold, an elderly mother is afraid of lighting fire.. (oops, a huge design fault). 12 deg inside, 300litres DHWT @mains cold.
There is an automatic coal delivery: every 1min 40 sec, spiral turns for 8 seconds, air pump set up to 15 (in scale 0-30).
I decided to torture (aka stress test) the system and kill some legionella bugs. Target: 75 Cels on rads and 75 inside DHWT (temporarily - I will reduce it appropriately), so after some tweaks, delivery 9 seconds, every 1:20min, air pump 15
Few questions though.
1. Ashes are approx 10% of the burnt coal volume. Barely any slag present. Good/bad?
2. I do not understand what is the purpose of the valve pictured. It has to be there as per manufacturer's blueprint, but what for? Is there a problem when cold water gets inside the boiler, hence the bypass, to slowly seep the warmth into the CH system?
3. System struggles to get to my desired deperatures (75 and 75). looks like 55CH/65DHW. Should I give it more air and fuel? Wait until the bulding warms up a bit more and then to tune the settings?
House got warmish in about 6 hours (16 cels), currently holds 19 degrees in all rooms, Tap hot at 65 after 24h. Used 25kg of coal.
I do get that this technology is widely frowned upon, but for less than £10 per day, it is quite tricky to heat the big house.
Any advice would be appreciated.