This past weekend I had a similar problem but it affected all my propane
appliances - very low flame on stove , poor fridge
performance . Upon investigation on the net I discovered that propane
regulators have a safety feature which restricts flow if a leak is detected , however this saftey device is sometimes fooled . Example - if the valve at the tank is turned off before an appliance is turned completely off , the next time it is used it will detect a leak , or if the tank is full and the valve is turned on quickly and full it detects an imbalance and restricts the flow . In either case the regulator will have to be reset before it will operate properly .
To reset regulator -
1] Turn off all appliances fully
2] Turn off valve at the tank
3] Disconect supply hose at the tank - wait about 2 minutes - the regulator will reset
4] Reconect supply hose at tank
5] Turn on valve at the tank SLOWLY about two turns only
6] Re-ignite appliances as normal
This procedure solved my problem , of course if there were a leak somewhere the problem would continue and need to be located and repaired .